Carrier 48GP Single Package Gas Heating Electric Cooling Units Instruction Manual

48GP, 48GPN
Single Package Gas Heating/Electric Cooling Units
With Puron® (R-410A) Refrigerant
Installation, Start-Up, and Operating Instructions
48GP, 48GPN Sizes 024-060

NOTE: Read the entire instruction manual before starting the installation.

NOTE TO INSTALLER Before the installation, READ THESE INSTRUCTIONS CAREFULLY AND COMPLETELY. Also, make sure the User’s Manual and Replacement Guide are left with the unit after installation, the furnace is NOT  to be used for temporary heating of buildings or structures under construction.

SAFETY CONSIDERATIONS

Installation and servicing of air-conditioning equipment can be hazardous due to system pressure and electrical components. Only trained and qualified personnel should install, repair, or sewice air-conditioning equipment.
Untrained personnel can perform basic maintenance functions of cleaning coils and filters. All other operations should be performed by trained sewice personnel. When working on air-conditioning equipment, observe precautions in the literature, tags and labels attached to the unit, and other safety precautions that may apply.
Follow all safety codes. Wear safety glasses and work gloves. Use quenching cloth for unbracing operations. Have fire extinguisher available lb all brazing operations.

C99088
Fig. 1–Unit 48GP

RULES FOR SAFE INSTALLATION AND OPERATION

WARNING
Improper installation, adjustment, alteration, service, maintenance, or use can cause carbon monoxide poisoning, fire, or an explosion which can result in serious injury or unit damage. Consult a qualified installer, service agency, or gas supplier for information or assistance. The qualified installer or agency must use only factory-authorized kits or accessories when modifying this product.
Understand the signal words DANGER, WARNING, and CAUTION. DANGER identifies the most serious hazards which will result in severe serious injury or death. WARNING indicates a condition that could result in serious injury or death. CAUTION is used to identify unsafe practices which would result in minor or moderate injury or product and property damage.
The power supply (volts, phase, and hertz) must correspond to that specified on unit rating plate.
The electrical supply provided by the utility must be sufficient to handle load imposed by this unit.
This installation must conform with local building codes and with NEC (National Electrical Code) and NFPA 70, NFPA 54 ANSI Z223.1 latest revision, and NFGC (National Fuel Gas (;ode). Refer to provincial and local plumbing or waste  water codes and other applicable local codes.
Approved for outdoor installation on wood flooring or on class A, B or C roof covering materials.
WARNING Before performing service or maintenance operations on unit, turn off gas supply then unit main power switch. Electrical shock or explosion could cause serious injurie or death.
CAUTION Puron (R-410A) systems operate at higher pressures than standard R-22 systems. Do not use R-22 service equipment or components on Puron (R-410A) equipment. Ensure service equipment is rated for Puron (R-410A).

GENERAL — The 48GP units (see Fig. 1) are fully self-contained, combination Category I gas heating’ electric cooling units designed for outdoor installation. See Fig. 6 and 7 for unit dimensions. All unit sizes have discharge openings for  both horizontal and downflow configurations, and are factory shipped with all downflow duct openings covered . Units may be installed  either on a rooftop, cement slab, or directly on the ground (if permitted by local codes). See Figs. 4 and 5 for roof curb dimensions.
48GPN units are dedicated Low NOx units designed for California installations. These models meet the California maximum oxides of nitrogen (NOx) emissions requirement of 40 nanograms; joule or less as shipped from the factory and MUST be installed in California Air Quality Management Districts where a Low NOx rule exists.

RECEIVING AND INSTALLATION

Step 1—Check Equipment
IDENTIFY UNIT — The unit model number and serial number are stamped on unit identification plate. Check this information against shipping papers and job data.
INSPECT SHIPMENT — Inspect for shipping damage while unit is still on shipping pallet. If unit appears to be damaged or is torn loose from its anchorage, have it examined by transportation inspectors before removal. Forward claim  papers directly to transportation company. Manufacturer is not responsible for any damage incurred in transit.
Check all items against shipping list. Immediately notify the nearest Carrier Air Conditioning office if any item is missing. To prevent loss or damage, leave all parts in original packages until installation.
Step 2—Provide Unit Support
ROOF CURB — Install accessory roof curb in accordance with instructions shipped with curb. See Figs. 4 and 5 and Table 1 for roof curb dimensions. Install insulation, cant strips, roofing, and flashing. Ductwork must be attached to  curb.
IMPORTANT: The gasketing of the unit to the roof curb is critical for a watertight seal. Install gasketing material supplied with the roof curb. Improperly applied gasketing can also result in air leaks and poor unit performance.
Curb should be level to within | /4 inch. This is necessary for unit drain to function properly. Refer to accessory roof curb installation instructions for additional information as required (see Fig. 2).
SLAB MOUNT — Place the unit on a solid, level concrete pad that is a minimum of 4 in. thick with 2 in. above grade. The slab should be flush on the compressor end of the unit (to allow condensate drain installation) and should extend  2 in. on the three remaining sides of the unit. See Fig. 3. Do not secure the unit to the slab except when required by local codes.

GROL_D MOUNT The unit may be installed either on a slab or placed directly on the ground if local codes permit. Place the unit on level ground prepared with gravel for condensate dis- charge.
Step 3—Field Fabricate Ductwork
Secure all ducts to roof curb and building structure on vertical discharge units. Do not connect ductwork to unit. For horizontal applications, unit is provided with flanges on the horizontal openings. All ductwork should be secured to the  flanges. Insulate and weatherproof ail external ductwork, joints, and roof openings with counter flashing and mastic m accordance with applicable codes.
Ducts passing through an unconditioned space must be insulated and covered with a vapor barrier.
If a plenum return is used on a vertical unit, the return should be ducted through the roof deck to comply with applicable fire codes. A minimum clearance is not required around ductwork. Cabinet return-air static shall not exceed -.25 in. wg.

Step 4—Provide Clearances
The required minimum operating and service clearances are shown in Fig. 6 and 7. Adequate combustion, ventilation, and condenser air must be provided, in accordance with section 5.3, Air for Combustion and Ventilation, of the National Fuel Gas Code ANSI (American National Standards Institute) 7223.1 (in Canada, see- tions 7.2, 7.3 or 7.4 or Can CGA [Canadian Gas Association] B149 Installation Codes), or applicable provisions of local building code.
CAUTION
Do not restrict condenser airflow. An air restriction at either the outdoor-air inlet or the fan discharge can be detrimental to compressor life.
The condenser pulls air through the condenser coil and discharges it through the top cover. Be sure that the fan discharge does not

Notes:

1. Roof curb must be set up for unit being installed
2. Seal strip must be applied as required to unit being installed
3. Dimensions in [ ] are in millimeters.
4. Roof curb is made of 16 gage steel.
5. Table Iists only the dimensions per part number that have changed.
6. Attach ductwork to curb (flanges of duct rest on curb)
7. Insulated panels: 1-in. thick fiberglass 1 lb. density
8. Dimensions are in inches

Table 1–Roof Curb Dimensions

recirculate to the condenser coil. Do not locate the unit in either a comer or under an overhead obstruction. The minimum clearance under a partial overhang (such as a normal house overhang) is 48-in. above the unit top. The maximum horizontal extension of a partial overhang must not exceed 48 inches. Do not place the unit where water, ice, or snow from an overhang or roof will damage or flood the unit. Do not install the unit on carpeting, tile, or other combustible  materials. The unit may be installed on wood flooring or on Class A, B, or C roof covering materials.
Step 5—Rig and Place Unit
Rigging and handling of this equipment can be hazardous for many reasons due to the installation location (roofs, elevated structures, ete.
Only trained, qualified crane operators and ground support staff should handle and install this equipment.
When working with this equipment, observe precautions in the literature, on tags, stickers and labels attached to the equipment, and any other safety precautions that might apply.
Training for operations of the lifting equipment should include, but NOT be limited to the following:

REQ’D CLEARANCES FOR OPERATION AND SERVICING in. (mm)
Evaporator coil access side ……………… 36 (914)
Power entry side (except for NEC requirements) ……… 36 (914)
Unit top …………………….. 48 (1219)
Side opposite ducts ………………… 36 (914)
Duct panel …………………… 12 (304.8)
Minimum distances:
If unit is placed Ies than 12 in. (3048 mm) from wall system, then the system performance may be compromised.
LEGEND
CG – Center of Gravity
COND – Condenser
EVAP – Evaporator
NEC – National Electrical Code
REQ’D – Required
Note: Dimensions are in in (mm)

REQ’D CLEARANCES TO COMBUSTIBLE MAT’L in. (mm)
Top of unit ……………………. 14 (355.6)
Duct side of unit ………………….. 2 (50.8)
Side opposite ducts ………………… 14 (355.6)
Bottom of unit ………………….. 0.50 (12.7)
Flue panel ……………………. 36 (914.4)
NEC REQ’D CLEARANCES. in (mm)
Between units, power entry side ………….. 42 (1066.8)
Unit and ungrounded surfaces, power entry side ……..  36 (914)
Unit and block or concrete walls and other grounded
surfaces, control box side …………….. 42 (1066.8)

REQUIRED CLEARANCE FOR OPERATION AND SERVICING in. [mm] EVAR COIL ACCESS SIDE …………………………………………………….. 3600 [914 6] POWER ENTRY SIDE ……………………………………………………………. 3600 [914 O] (EXCEPT FOR NEC REQUIREMENTS)
UNIT TOP …………………………………………………………………………….. 3600 [914.0] SIDE OPPOSITE DUCTS ………………………………………………………. 3600 [914.0] DUCT PANEL ……………………………………………………………………….. 1200 [304 8]
MINIMUM DISTANCES: IF UNIT IS PLACED LESS THAN 12.00 [304.8] FROM WALL SYSTEM, THEN SYSTEM PERFORMANCE MAYBE COMPROMISE

REQUIRED CLEARANCE TO COMBUSTIBLE MATE in [mm] TOP OF UNIT ……………………………………………………………………….. 14.00 [355.6] DUCT SIDE OF UNIT ………………………………………………………………. 2.00 [508] SIDE OPPOSITE DUCTS ………………………………………………………. 14.00 [355.6] BOTTOM OF UNIT ………………………………………………………………….. 0.50 [12.7] ELECTRIC HEAT PANEL ……………………………………………………….. 36.00 [914.4] NEC.REQUIREDCLEARANCES.
MILLIMETERS [IN] BETWEEN UNITS, POWER ENTRY SIDE ……………………………… 4200 [1066.8] UNIT AND UNGROUNDED SURFACES, POWER ENTRY Side .3600 [914.0] UNIT AND BLOCK OR CONCRETE WALLS AND OTHER GROUNDED SURFACES, POWER ENTRY SIDE ……………………. 42.00 [1066.8]

1. Application of the lifter to the load and adjustment of the lifts, if any, that adapts it to various sizes or kinds of loads.
2. Instruction in any special operation or precaution.
3. Condition of the load itself, required for operation of the lifting kit, such as balance, temperature, etc.
   Follow all applicable safety codes. Wear safety shoes and work gloves.

WARNING
Never exceed 200 lbs. per bracket lifting force.
Accessory lifting kit is only to be used with Small Packaged units which have a composite base pan with molded hand holds.
Never stand beneath rigged units or lift over people.
Lifting point should be directly over the center of gravity for the unit.
A dropped unit could cause serious injury or death.

INSPECTION
Prior to initial use, and at monthly intervals, all rigging brackets and straps should be visually inspected lb any damage, evidence of wear, structural deformation, or cracks. Particular attention should be paid to excessive wear at hoist hooking points and load support areas. Brackets or straps showing any kind of wear in these areas nest not be used and should be discarded.
INSTALLATION:

1. Position the lifting bracket assembly around the base of the unit. Leave the top shipping skid on the unit to act as a spreader bar. Be sure the strap does not twist.
2. Place each of the four (4) metal lifting brackets into the handholds in the composite pan.
3. Tighten the ratchet strap until tight. Lifting brackets should be secure in the handholds.
4. Attach the clevis or hook of sufficient strength to hole in the lifting bracket as shown in Fig. 8.
5. Attach safety straps directly to the field supplied rigging straps or clevis clip. Do not attach the safety straps to the lifting brackets.
6. Use the top of the unit as a spreader bar to prevent the rigging straps from damaging the unit. If the wood top is not available, use a spreader bar of sufficient length to not damage the unit.

Belt Threading Instructions:

1. Open lever of tension buckle
2. Feed webbing through tension buckle as shown
3. Pull webbing through tension buckle until taught
4. Snap lever down to lock strap in tension buckle
5. To release, squeeze safety latch, lift lever and pull webbing outward
   Fig. 9–Belt Threading

Step 6—Connect Condensate Drain

NOTE: When installing condensate drain connection be sure to comply with local codes and restrictions.
The 48GP units dispose of condensate water through a 3/4 in, NPT fitting which exits through the compressor access panel. See Fig. 6 and 7 for location.
Condensate water can be drained directly onto the roof in rooftop installations (where permitted) or onto a gravel apron in ground- level installations. Install a field-supplied condensate trap at end of condensate connection to ensure  proper damage. Make sure that the outlet of the trap is at least 1 in. lower than the drain pan condensate connection to prevent the pan from overflowing. See Fig. 11. Prime the trap with water. When using a gravel apron, make sure it slopes away from the unit.
If the installation requires draining the condensate water away from the unit, install a 2-in. trap at the condensate connection to ensure proper drainage. See Fig. 11. Make sure that the outlet of the trap is at least 1 in. lower than the drain  pan condensate connection to prevent the pan from overflowing. Prime the trap with water. Connect a drain tube using a minimum of 3/4 -in. PVC or 3/4 -in. copper pipe (all field-supplied) at the outlet end of the 2-in. trap. Do not  undersize the tube. Pitch the drain tube downward at a slope of at least one in. for every 10 ft of horizontal run. Be sure to check the drain tube for leaks.

Step 7—Install Flue Hood
The Nue hood assembly ts shipped screwed to the coil panel in the indoor blower compartment. Remove the service access panel to locate the assembly.
Dedicated low NOx 48GP models MUST be installed in California Air Quality Management Districts where a Low NOx rule exists. These models meet the California maximum oxides of nitrogen (NOx) emissions requirement of 40 nanograms: joule or less as shipped from the factory.
NOTE: Low NOx requirements apply only to natural gas installations.
CAUTION
The venting system is designed to ensure proper venting. The flue hood assembly must be installed as indicated in this section of the unit installation instructions. Install the flue hood as tallows:

1. This installation must conform with local building codes and with the National Fuel Gas Code (NFGC), ANSI 2223.1 (in Canada, CAN CGA B149.1, and B149.2) or NFPA (National Fire Protection Association) latest revision. Refer to  Provincial and local plumbing or waste water codes and other applicable local codes.
2. Remove flue hood from shipping location (inside the blower compartment). Place vent cap assembly over flue panel. Orient screw holes m vent cap with holes in the flue panel.
3. Secure flue hood to flue panel by inserting a single screwin the right side and the left side of the hoed.

Step 8—Install Gas Piping
The gas supply pipe enters the unit through the access hole provided. The gas connection to the unit is  made to the 1-2-in. PPT gas inlet on the manual shutoff or gas valve.
Install a gas supply line that runs to the heating section. Refer to Table 4 and the NFGC for gas pipe sizing. De not use cast-iron Pipe. It is recommended that a black iron pipe is used. check the local utility for recommendations conceding existing lines. Size gas supply piping for 0.5 in. wg maximum pressure drop. Never use pipe smaller than the 1/2-in. FPT gas inlet on the unit gas valve.
For natural gas applications, the gas pressure at unit gas connection must not be less than 4.0 in. wg or greater than 13 in. wg while the unit is operating. For propane applications. the gas pressure must not be less than 7.0 in. wg or greater than 13 in. wg at the unit connection.
A 1’8-in. NPT plugged tapping accessible for test gage connection must be installed immediately upstream of the gas supply connection to the gas valve.
When installing the gas supply line. observe local codes pertaining to gas pipe installations. Refer to the NFGC ANSI 2223.1, NFPA $4 latest edition (in Canada. CAN’CGA B149.1, B149.2 latest edition). In the absence of local building  codes, adhere to the following pertinent recommendations:

1. Avoid low spots in long runs of pipe. Grade all pipe 14 in. in every 15 ft. to prevent traps. Grade all horizontal runs downward to risers. Use risers 10 connect to heating section and to meter.

2. Protect all segments of piping system  against physical and thermal damage. Support all piping with appropriate straps, hangers, ete. Use a minimum of one hanger every 6 ft. For pipe sizes larger than 1/2 in., follow recommendations of national codes.

3. Apply joint  compound (pipe dope) sparingly and only to male threads of joint when making pipe connections. Use only pipe dope that is resistant to action of liquefied petroleum gases as specified by local and/or national codes. Never use  Teflon tape.

4. Install sediment trap in riser leading to heating section per Fig. 12. This drip leg functions as a trap for dirt and condensate.

5. Install an accessible. external, manual main shutoff valve in gas supply pipe within 6 fi. of  heating section.

6. Install ground-joint union close to heating section between unit manual shutoff and external manual main shutoff valve.

7. Pressure-test all gas piping in accordance with local and national plumbing and gas codes  before connection of piping to unit. NOTE: The supply piping must be disconnected tromp the gas valve during the testing of the piping systems when test pressure is in excess of 0.5 psig 13.8 WC) If the test pressure ts equal to or fess than 0.5 psig. the unit heating  section must be isolated from the gas piping system by closing the external main manual shutoff valve and tightly opening the ground-joint union.
   CAUTION
   Unstable operation may occur when the gas valve and manifold assembly are forced out of position while connecting improperly routed rigid Gus piping to the gas valve. Use a backup wrench when making connection to avoid strain  an, or distortion of, the gas control piping.
   CAUTION
   If a flexible conductor is required or allowed by the authority having jurisdiction, black iron pipe shall be installed at the gas valve and shall extend a minimum of 2 in. outside the unit casing.
   WARNING
   Never use a match or other open flame when checking for gas leaks, Never purge gas line into combustion chamber. Failure to follow this warning could result in an explosion causing serious injury or death

8. Cheek tor gas leaks at the field-installed and factory-installed gas lines after all piping connections have been completed. Use soap and water solution (or method specified by local codes and-or regulations).

Step 9—Install Duct Connections

The unit has duct flanges on the supply- and returneair openings on the side and bottom of the unit. For downshift applications the ductwork can be connected to the roof curb See Fig. 6 and 7 for connection sizes and locations.
CONFIGURING UNITS FOR DOWNFLOW (VERTICAL) DIS-CILARGE
WARNING
Refore performing service or maintenance operations on the system. turn off main power to unit. Electrical shock could valise serious miry or death,

1. Open all electrical disconnects before starting any service work.

2. Remove return duct cover located on duct panel by breaking connecting tabs with screwdriver and a hammer (Fig. 13).

3. To remove supply duct cover. break front and right side connecting tabs with a screwdriver and a hammer. Push louver down to break rear and left side tabs (Fig. 14).

4. If omit ductwork is to be attached to vertical opening flanges on the ump baseman (cabstand applications only). do so at this time. Collect ALL screws that were removed. Do not leave srews on rooftop as permanent damage to the  roof may occur,

5. It is recommended that the baseman insulation around the perimeter of the vertical retum-air opening be secured to the baseman with aluminum tape. Applicable local codes may require aluminum tape to prevent exposed  fiberglass.

6. Cover both horizontal duct openings with the duct covers tromp the accessory duct cover kit, Ensure opening is air-and watertight. *Capacity of pipe in cu ft. of gas per hr for gas pressure of 0.5 psig or less. Pressure drop of 0 5-in. wg (based on a 0.60 specific gravity gas) Refer to Table C-4, National Fire Protection Association NFPA 54
   1-This length includes an ordinary number of fittings.

7. After completing unit conversion, perform all safety checks and power up unit.

NOTE: The design and installation of the duct system must be in accordance with the standards of the NFPA for installation of nonevidence-type air conditioning and ventilating systems, NFPA 90A or residence-type, NFPA 90B: andar  local codes and residence-type, NFPA 90B; andar local codes and ordinances. ADHERE TO THE FOLLOWING CRITERIA WIEN SELECT-  ING, SIZING, AND INSTALLING THE DUCT SYSTEM:

1. Units are shipped for side shot installation.
2. Select and size ductwork, supply-air registers, and return-air grilles according to American Society of Heating, Refrigeration and Air Conditioning Engineers (ASIIRAE) recommendations.
3. Use flexible transition between rigid ductwork and unit to prevent transmission of vibration. The transition may be screwed or bolted to duct flanges. Use suitable gaskets to ensure weather tight and airtight seal.
4. All units must have field-supplied filters or accessory filter rack installed in the return-air side of the unit. Recommended sizes for filters are shown in Tables 2 and 3.
5. Size all ductwork for maximum required airflow (either heating or cooling) for unit being installed. Avoid abrupt duct size increases or decreases or performance may be affected.
6. Adequately insulate and weatherproof all ductwork located outdoors. Insulate ducts passing through unconditioned space, and use vapor barrier in accordance with latest issue of Sheet Metal and Air Conditioning Contractors  National Association (SMACNA) and Air Conditioning Contractors of America (ACCA) minimum installation standards for heating and air conditioning systems. Secure all ducts to building structure.
7. Flash, weatherproof, and vibration-isolate all openings in building structure in accordance with local codes and good building practices.

Step 10–Install Electrical Connections
WARNING

The unit cabinet must have an uninterrupted, unbroken electrical ground to minimize the possibility of serious injury fan electrical fault should occur. This ground may consist of an electrical wire connected to the unit ground lug in the
control compartment. or conduit approved for electrical ground when installed in accordance with NEC (Nanonal Floterial Code) ANST NFPA 70 (latest edition) Gin Canada. Canadian Electrical Code CSA [Canadian Standards
Association] C221) and local electrical codes, Do nor use gas piping as un electrical ground. Failure to adhere lo this warning could result in serious injury or death.
CAUTION

Failure to follow these precautions could result in damage to the unit being installed:

1. Make all electrical connections in accordance with NEC ANSPNEPA 70 (latest edition) and local electrical codes governing such wiring. In Canada, all electrical connections must be in accordance with CSA standard C22.1 Canadian  Electrical Code Part 1 and applicable local codes. Refer to unit wiring diagram.
2. Use only copper conductor for connections between field-supplied electrical disconnect switch and unit. DO NOT USE ALUMINUM WIRE.
3. Be sure that high-voltage power to unit is within operating voltage range indicated on unit rating plate.
4. Do not damage internal components when drilling through any panel to mount electrical hardware, conduit, ete.
5. On 3-phase units, ensure phases are balanced within 2°. Consult local power company for correction of improper voltage andar phase imbalance (refer to Table 5),

HIGH-VOLTAGE CONNECTIONS — The unit must have a separate electrical service with a fiekl-supplied. water-proof, disconnect switch mounted at, or within sight from the unit, Refer to the unit rating plate for maximum fuse circuit  breaker size and minimum circuit amps (ampacity) for wire sizing. See Table § for electrical data.
The field-supplied disconnect switch box may be mounted on the unit over the high-voltage inlet hole when the standard power and low-voltage entry points are used. See Fig. 6 and 7 for acceptable location.
See unit wiring label and Fig. 16 for reference when making high voltage connections. Proceed as follows to complete the high- voltage connections to the unit.
Single phase units:

1. Run the high-voltage (L1, L2) and ground leads into the control box.
2. Connect ground lead to chassis ground connection.
3. Connect L) to pressure lug connection |! of the compressor contactor.
4. Connect L2 to pressure Jug connection 23 of the compressor contactor.

Three phase units:

1. Run the high-voltage (L1. L2. L3) and ground feeds into the control box.
2. Connect ground lead to chassis ground connection.
3. Locate the black and yellow wires connected to the lines side of the contactor.
4. Connect field L1 to black wire on connection 11 of the compressor contactor.
5. Connect held wire L2 to yellow wire on connection 13 of the compressor contactor.
6. Connect field wire L3 to Blue wire from compressor. SPECIAL PROCEDURES FOR 208-V OPERATION

WARNING
Make sure that the gas supply ‘en the power supply to the unit is switched OFF before making any wiring changes. Flectrical shock or explosion could cause serious injury or death.
With disconnect switch open, move yellow wire from transformer (3-16 in.) terminal marked 230 to terminal marked 200. This reaps transformer to primary voltage of 208 vac.
LEGEND
FLA — Full Load Amps
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps
MOCP — Maximum Overcurrent Protection
RLA — Rated Load Amps
NOTES:

1. In compliance with NEC (National Electrical Code) requirements for multirotor and combination toad equipment (refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall be Power Supply fuse. The  CGA (Canadian Gas Association) units may be fuse or circuit breaker.
2. Minimum wire size is based on 60 C copper wire. If other than 60 C wire is used, or if length exceeds wire length in table, determine size from NEC.
3. Unbalanced 3-Phase Supply Voltage
   Never operate a motor where a phase imbalance in supply voltage is greater than 2%. Use the following formula to determine the percentage of voltage imbalance.
   % Voltage imbalance

= 100 x max voltage deviation from average voltage average voltage

Determine maximum deviation from average voltage.
(AB) 457 452 = 5 v
(BC) 464 457 = 7 v
(AC) 457 455 = 2 v
Maximum deviation is 7 v.
Determine percent of voltage imbalance.

This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%.
IMPORTANT:
If the supply voltage phase imbalance is more than 2%, contact your local electric utility company immediately.
Fig. 15–Electrical Data Legend
CONTROL VOLTAGE CONNECTIONS
NOTE: Do not use any type of power-stealing thermostat. Unit control problems may result.
Use no. 18 American Wire Gage (AWG) color-coded, insulated (35 C minimum) wires to make the control voltage connections between the thermostat and the unit. If the thermostat is located more than 100 ft from the unit (as measured along the control! voltage wires), use no. 16 AWG color-coded, insulated (35 C minimum) wires.
STANDARD CONNECTION — Remove knockout hole located in the flue panel adjacent to the control access panel. See Fig. 6 and 7. Remove the rubber grommet from the installer’s packet (included with unit) and install grommet in  the knockout opening. Provide a drip loop before running wire through panel.
Run the low-voltage leads from the thermostat, through the inlet hole, and into unit low-voltage splice box.
Locate five 18-gage wires leaving control box. These low-voltage connection leads can be identified by the colors red, green, yellow, brown, and white. (See Fig. 16.) Ensure the leads are long enough to be routed into the low- voltage splice  box (located below right side of control box). Stripped yellow wire is located in connection box. Route leads through hole in bottom of control box and make low-voltage connections as shown in Fig. 16. Secure all cut wires, so that they do not interfere with operation of unit.

HEAT ANTICIPATOR SETTING — The room thermostat heat anticipator must be properly adjusted to ensure proper heating performance. Sct the heat anticipator, using an ammeter between the W and R terminals to detennine the exact required setting.
NOTE: For thermostat selection purposes, use 0.18 amp for the approximate required setting.
Failure to make a proper heat anticipator adjustment will result in improper operation, discomfort lo the occupants of the conditioned space, and inefficient energy utilization: however. the required setting may be changed slightly to  provide a greater degree of coniform for a particular installation.
TRANSFORMER PROTECTION — The transformer is of the energy-limiting type. It is set to withstand a 30-second overload or shorted secondary condition.
PRE-START-UP
WARNING

Failure to observe the following wamings could result in serious injury or death:

1. Follow recognized safety practices and wear protective goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric power to unit unless compressor terminal cover is in place and secured,
3. Do not remove compressor terminal cover until all electrical sources are disconnected.
4. Relieve and recover all refrigerant from both high- and low-pressure sides of system before touching or disturbing anything inside terminal box if refrigerant leak is suspected around compressor terminals.
5. Never attempt to repair soldered connection while refrigerant system is under pressure.
6. Do not use torch to remove any component. System  contains oil and refrigerant under pressure. To remove a component, wear protective  goggles and proceed as follows:
   a. Shut off gas supply and ten electrical power to unit.
   b. Relieve and reclaim all refrigerant from system using both high- and low- pressure parts.
   ¢. Cut component connecting tubing with cubing  cutter and remove component from unit.
   d. Carefully unsweet remaining tubing stubs when necessary. Oil can ignite when exposed to torch flame.

Proceed as follows to inspect and prepare the unit for initial  startup:

1. Remove access panel.

2. Read and follow instructions on all DANGER, WARNING,
   CAUTION, and INFORMATION labels attached to. or shipped with, unit.

3. Make the following inspections:
   a. Inspect for shipping and handling damages such as broken lines, loose parts. disconnected wires, ete.
   b. Inspect for oil at all refrigerant tubing connections and on unit base. Detecting oil generally indicates a refrigerant leak. Leak test all refrigerant tubing connections using electronic leak detector, halide torch, or liquidseap solution. If a refrigerant leak is detected, see Cheek for Refrigerant Leaks section on page 13.
   c. Inspect all field- and factory-wiring connections. Be sure that connections are completed and tights.
   d. Inspect coil fins. If damaged during shipping and handling. carefully straighten fins with a fin comb.

4. Verify the following conditions:

WARNING
Do net purge gas supply into the combustion chamber. Do not use a match or other open flame to check for gas leaks. Failure to follow this warning could result in an exposion causing serious injury or death.
a, Before lighting the unit for the first time, perform the following with the gas valve in the “OFF” position: If the gas supply pipe was not purged before connecting the unit, will be full of air. It is recommended that the ground joint  union be loosened, and the supply line be allowed 😮 purge until the odor of gas is detected. Never purge gas ins into a combustion chamber. Immediately upon detection of gas odor, re-tighten the union, Allow 4 minutes to elapse, then  light unit.
b. Make sure that condenser-fan blade 1s correctly positioned in fan orifice. Leading edge of condenser-fan blade should be £2 in. maximum from fan orifice (see Fig. 17).
c. Ensure fan hub ts 1-8 in. max from motor housing.
d. Make sure that air filter(s) is in place.
e. Make sure that condensate drain trap 1s filled with water to ensure proper drainage.
f. Make sure that all tools and miscellaneous loose parts have been removed.

START-UP
Use the Start-Up Checklist supplied at the end of this book, and proceed as follows:
CHECK FOR REFRIGERANT LEAKS — Proceed as follows to locate and repair refrigerant leaks and charge the unit:

1. Locate leak and make sure that refrigerant system pressure has been relieved and refrigerant recovered from both bnght- and low-pressure ports.

2. Repair leak following accepted practices.
   NOTE: Replace filter drier whenever the system has beer opened for repair.

3. Cheek system for leaks using an approved method.

4. Evacuate refrigerant system and reclaim refrigerant if no  additional leaks are found.

5. Charge unit with R-410a refrigerant. using a volumetric-charging cylinder or aceturate scale. Refer 10 unit raring plate for required charge.

Table 6–Heating Inputs

HEATING INPUT
(BTUH)*| NUMBER OF
ORIFICES| GAS SUPPLY PRESSURE (IN. WG)| MANIFOLD PRESSURE (IN. WG)
---|---|---|---
Natural| Propanet
Min| Max| Min| Max| Natural| Propanet
40,000| 2| 4.0| 13.0| 7.0| 13.0| 4.| 4.
60,000| 2| 4.0| 13.0| 7.0| 13.0| 4.| 4.
90,000| 3| 4.0| 13.0| 7.0| 13.0| 4.| 4.
115,000| 3| 4.0| 13.0| 7.0| 13.0| 4.| 4.
130,000| 3| 4.0| 13.0| 7.0| 13.0| 4.| 4.

*When a unit is converted to propane, different size orifices must be used. See separate nature-to-propane conversion kit instructions
1-Based on altitude’s from sea level to 2000 ft. above sea leve. For altitudes above 2000 ft., reduce input rating 4% for each 1000 ft above sea Level. in Canada, from 2000 ft above sea level to 4500 ft above sea Ievelderate the unit 10%
START UP HEATING SECTION AND MAKE ADIUSTMENTS
IMPORTANT: Complete the required procedures given in the Pre-Start-Up section above before starting the unit.
Do not jumper any safety devices when operating the unit.
Make sure that bummer orifices are properly aligned. Unstable operation may occur when the burner orifices in the manifold are misaligned.
NOTE: Make sure that gas supply has been purged, and that all gas piping has been checked for leaks.
CHECK HEATING CONTROT Start and cheek the unit for proper heating control operation as follows. (see furnace lighting instructions located inside burner or blower access panel):

1. Place room thermostat SYSTEM switch in the HEAT position and the FAN switch in the AUTO position.
2. Set the heating temperature control of the thermostat above room temperature.
3. The induced-draft motor will start.
4. After a call for heating. the main burner should light within 5 seconds. If the burners do not light. there is 4 22-secand delay before another 5-second try. [f the bummers still] do not light. this sequence is repeated. If the burners do not  light within 15 minutes from the initial call for heat. there is a lockout. To reset the control. break the 24-v power to W.
5. The evaporator fan will tum on 45 seconds after the Name has been established. The evaporator fan will turn off 45 seconds afler the thermostat has been satisfied.

CHECK GAS INPUT —Check gas input and manifold pressure after unit start- up (Sec Table 6.) If adjustment is required, proceed as follows:
The rated gas inputs shown in Table 6 are for altitudes from sea level to 2000 ft. above sea level. These inputs are based on natural gas with a beating value of 1050 Btw: ft’ at 0.6$ specific gravity, or propane gas with a heating value of  2500 Bruit® at 1.5 specific gravity. For elevations above 2000 f.. reduce input 4% for cach 1000 ft. above sea level, When the gas supply being used has a different heating value, or specific gravity, refer to nahual and local codes, or  contact your distributor to determine the required orifice size,
CAUTION
These omits are designed to consume the rated gas inputs using the fixed orifices at specified manifold pressures as shown in Table 6. DO NOT REDRILL THE ORIFICES UNDER ANY CIRCUMSTANCES.
ADJUST GAS INPUT— The gas input to the unit is determined by measuring the gas flow at the meter or by measuring the manifold pressure. Measuring the gas flow at the meter is recommended for natural gas units. The manifold pressure must be measured to determine the put of propane gas units.
MEASURE GAS FLOW (Natural Gas Units} —Minor adjustment to the gas flow can be made by changing the manifold pressure.
The manifold pressure must be maintained between 3.4 and 3.6 in. we. If larger adjustments are required, change main burner orifices following the recommendations of national local codes.
NOTE: All other appliances that use the same meter must be turned off when gas flow is measured at the meter.
Proceed as follows:
Turn off gas supply to unit.

1. Remove pipe plug on manifold (see Fig. 18) then connect manometer at this point. tum on gas to unit.
2. Record number of seconds for gas meter test dial to make one revolution.
3. Divide number of seconds in Step 3 into 3600 (number of seconds on one hour).
4. Multiply result of Step 4 by the number of cu. ft. shown for one revolution of test dial to obtain cu. ft. of gas flow per hour.
5. Multiply result of Step 5 by Btu heating value of gas to obtain total measured input in Btuh. Compare this value with heating input shown in Table 6. (Consult the local gas supplier if the heating value of gas is not known.)

EXAMPLE: Assume that the size of test dial is 1 cu. f., one revolution takes 32 seconds. and the heating value of the gas is 1050 Betwixt®. Proceed as follows:

1. 32 seconds to complete one revolution.
2. 3600 + 32 = 112.5
3. 112.8 x 1 = 112.5 ft® of gas flower,
4. 112.5 x 1050 = 118,125 Buh input.

If the desisted gas input is 115,000 Btuh, only a minor change in the manifold pressure is required.
Observe manifold pressure and proceed as follows to adjust gas input:

1. Remove cover screw over regulator adjustment screw on gas valve.

2. Tum regulator adjustment screw clockwise to increase gas input, or turn regulator adjustment screw counterclockwise to decrease input. Manifold pressure must be between 3.4 and 3.6 in. we. WARNING
   Unsafe operation of the unit may result if manifold pressure is outside this range. Serious injury or unit damage may result.

3. Replace cover screw cap on gas valve.

4. Turn off gas supply to unit. Remove manometer from pressure tap and replace pipe plug on gas valve. Turn on gas to unit and check for leaks.

MEASURE MANIFOLD PRESSURE (PROPANE UNITS)
The main burner orifices on a propane unit are sized for the unit rated input when the manifold pressure reading matches the level specified in Table 6.
WARNING
If converting to propane gas, remove the burner assembly and inspect the heat exchanger robes. If there are V-shaped NOx baffles installed in the firing tubes, THEY MUST BE REMOVED.
Discard the baffles after removal.
Refer to Maintenance section for information on burner removal.
Proceed as follows to adjust gas input on a propane gas unit:

1. Turn off gas to unit.
2. Remove pipe plug on manifold (see Fig. 18) then connect manometer at this point.
3. Turn on gas to unit.
4. Remove cover screw over regulator adjustment screw on gas valve.
5. Adjust regulator adjustment screw to the correct manifold pressure, as specified in Table 6. Turn adjusting screw clockwise to increase manifold pressure, or turn adjusting screw counterclockwise to decrease manifold pressure.
6. Replace cover screw.
7. Turn off gas to unit. Remove manometer from pressure tap.
   Replace pipe plug on gas valve, then turn on gas to unit. check for leaks.

CHECK BURNER FLAME With burner access panel removed, observe the unit heating operation. Watch the burner flames to see if they are light blue and soft in appearance, and that the flames are approximately the same for each burner. Propane will have blue flame with yellow tips. (See Fig. 19). Refer to Maintenance section for information on burner removal.

AIRFLOW AND TEMPERATURE RISE The heating section for each size unit is designed and approved for heating operation within the temperature rise range stamped on the unit rating plate. Table 7 shows the approved temperature rise range for each heating  input, and the air delivery chin at various temperature rises. The heating operation airflow must produce a temperature rise that falls within the approved range. Refer to Indoor Airflow and Airflow Adjustments section on the following pages to adjust heating airflow when required.

NOTE: Dashed areas do not fall within the approved temperature rise range of the unit.

HEATING SEQUENCE OF OPERATION See Fig. 20-22 and unit wiring label. On a call for heating, terminal “W” of the thermostat is energized, starting the induced-draft motor. When the hall-effect sensor on the induced-draft motor senses that it has reached the required speed, the burner sequence begins. This function is perfumed by the integrated gas control (IGC). The evaporator fan motor is energized 45 seconds after flame is established. When the thermostat is satisfied and “W” is de-energized, the burners stop firing and the evaporator fan motor shuts off after a 45-second time-off delay. An LED (light-emitting diode) indicator is provided on the control board to monitor operation. The control board is located by removing the burner access panel. During normal operation, the LED is continuously on. See Table 8 for error codes.

Table 8 LED Indications

NOTES:

1. There is a 3-second pause between error code displays
2. If more than one error code exists, all applicable error codes wilt be displayed in numerical sequence.
3. This chart is on the wiring diagram located inside the burner access panel

LIMIT SWITCHES Normally closed limit switch (LS) com- plates the control circuit through the thennostat R circuit. Should the leaving-air temperature rise above the maximum allowable temperature, the limit switch opens and the R control circuit “breaks”. Any interruption in the R control circuit instantly closes the gas valve and stops gas flow to the burners and pilot. The blower motor continues to run until LS resets.
When the air temperature at the limit switch drops to the low-temperature setting of the limit switch, the switch closes and completes the R control circuit. The electric spark ignition system cycles and the unit returns to normal heating operation. When this Ault occurs, the IGC LED will display FAULT CODE 2.
AUXILIARY LIMIT SWITCH (ROLLOUT) The function of the switch is to close the main gas valve in the event of flame rollout. The switch is located above the main bummers. When the temperature at the auxiliary switch reaches the maximum allow- able temperature, the R control circuit trips, closing the gas valve and stopping gas flow to the burners. The indoor (evaporator) fan motor (IFM) and induced draft motor continue to run until switch is reset. The IGC LED will display FAULT CODE 7.
START UP COOLING SECTION AND MAKE AD,RTSTMENTS
CAUTION
Complete the required procedures given in the Pre-Start-Up section on previous pages belote starting the Unit.
Do not jumper any safety devices when operating the unit.
Do not operate the compressor when the outdoor temperature is below 40° F (unless accessory low-ambient kit is stalled). Do not rapid-cycle the compressor. Allow 5 minutes between “on” cycles to prevent compressor damage.
CHECKING COOLING CONTROL OPERATION — Start and cheek the unit for proper cooling control operation as follows:

1. Place room thermostat SYSTEM switch in OFF position. Observe that blower motor starts when FAN switch is placed in ON position and shuts down when FAN switch is placed in AUTO position.
2. Place SYSTEM switch in COOL position and FAN switch in AUTO position. Set cooling control below room temperature. Observe that compressor, condenser fan, and evaporator blower motors start. Observe that cooling cycle shuts down when control setting is satisfied. The evaporator fan will continue to run for 30 seconds.
3. When using an auto-changeover room thermostat. place both SYSTEM and FAN switches in AUTO positions. Observe that unit operates in Heating mode when temperature control is scot to “call for heating” {above room  temperature) and operates in Cooling mode when temperature control! is set to “call for cooling” (below room temperature).

WWIPORTANT: Three-phase, scroll compressor units — are direction- oriented. These units must be checked to ensure proper compressor 3-phase power lead orientation. [f not corrected within 5 minutes, the internal protector will  shut off the compressor. The 3-phase power leads to the unit must be reversed to correct rotation. When turning backwards. scroll compressors emit elevated noise levels, and the difference between compressor suction
and discharge pressures may be dramatically lower than normal.
CHECKING AND ADJUSTING REFRIGERANT CHARGE
— The refrigerant system is fully charged with R-410A (Puron) refrigerant, and is tested and factory sealed.
NOTE: Adjustment of the refrigerant charge is not required wales the unit is suspected of not having the proper R-410A charge. The charging label and the tables shown refer to system temperatures and pressures.
A refrigerant charging chart label is attached to the outside of the compressor access door. The chart includes the required suction line temperature at given suction line pressures and outdoor ambient..
An accurate superheat, thermocouple- or thermistor-type_ ther- myometer, and a gage manifold are required when using the superheat charging method for evaluating the unit charge. Do nor use mercy’s or small dial-type thermometers because they are not adequate for this type of measurement

IMPORTANT: When evaluating the refrigerant charge, an indicated adjustment to the specified factory charge must always be very minimal. If’ a substantial adjustment is indicated, an anconal condition exists somewhere in the cooling system, such as insufficient airflow across either coil or both coils. REFRIGERANT CILARGE — The amount of refrigerant charge is listed on the unit nameplate, Refer to Carrier Refrigeration Service Techniques Manual, Refrigerants section. Unit panels must be in place when unit is operating during charging procedures. NO CHARGE: Use standard evacuating techniques. Afler evacuating system, weigh in the specific amount of refrigerant (refer to system data plate).
LOW CITARGE COOLING: Measure outdoor ambient using Cooling Charging Charts (Figs, 23-28). Vary refrigerant until the conditions of the chart are met. Note that charging charts are diferent from type normally used. Charts are based on charging the units to correct superheat for the various operating conditions. Accurate pressure gage and temperature sensing devices are required. Connect the pressure gage to the service port on the suction line. Mount the temperature sensing device on the suction line and insulate it so that the outdoor ambient does not effect the reading. Indoor air CFM must be within the normal operating yang of the unit. TO USE COOLING CHARGING CHARTS: Take the outdoor ambient temperature and read the suction pressure gage. Refer to the chart to determine what the suction temperature should be. NOTE: If the problem causing the inaccurate readings is a refrigerant leak. refer to Check for Refrigerant Leaks section in this document.
INDOOR AIRFLOW AND AIRFLOW ADJUSTMENTS
CAUTION For cooling operation. the recommended airflow is 350 to 450 cfm for cach 12,000 But of rated cooling capacity. For heating operation. the airflow must produce a temperature rise that falls within the range stamped on the unit rating plate.
‘Table 7 shows the temperature rise at various air-flow rates. Table 9 shows both heating and cooling airflows al various external static pressures. Ruler to these labels to determine the airflow for the system being installed.
NOTE: Be sure that all supply- and return-air grilles are open. tree from obstructions, and adjusted properly.
WARNING
Shut off gas supply drew disconnect electrical power to the unit before changing blower speed. Electrical shock or explosion could cause serious injury or death.
Airflow can be changed by changing the lead connections of the blower motor.
All A8GP units are factory wired for low speed and may need to be wired for medium or high speed in the field.
For 208 230-v — The motor leads are color-coded as follows:

To change the speed of the blower motor (BM), remove the fan motor speed leg lead tromp the blower relay (BR). This wire ts attached to tensional BM for single-phase and 3-phase units. To change the speed, remove and replace with lead for desired blower motor speed. Insulate the removed lead to avoid contact with chassis parts.
For 460-. GE Motors — The moor leads are color coded as tallows:

To change the speed of the blower motor (BM), remove fan motor speed lead from the blower relay (BR) and replace with the lead for the desired blower motor speed. The motor speed lead 1s attached to terminal BM. For tow and  medium speeds black must be connected to the jumper wire. fafiate removed feed end to avoid contact with chassis parts. To select Hugh speed on 460-v GE motors, separate the black female quick connect (QC) from the jumper lead  male quick connect (QC) and connect the black lead to the BR. /sulfate the jumper to avoid contact with and chassis Paris

Table 9–Wet Coil Air Delivery* — Horizontal and Downflow Discharge Unit 48GP024-060 (Deduct 10% for 208 Volts)*
Air delivery values are without air filter.
Note: Deduct field-supplied air filter pressure drop to obtain external static pressure available for ducting
COOLING SEQUENCE OF OPERATION — With the room thermostat SYSTEM switch in the COOL position and the FAN switch in the AUTO. position, the cooling sequence of operation is as follows:
When the room temperature rises to a port that is slightly above the cooling control setting of the thermostat, the thermostat completes the circuit between thermostat terminal R to terminals Y and G. These completed circuits through  the thermostat connect contactor coil (C) (through unit wire Y) and blower relay coil (BR) (through unit wire G) across the 24-v secondary of transformer (TRAN).
The normally open contacts of energized contactor (C) close and complete the circuit through compressor motor (COMP) to con- denser (outdoor) fan motor (OFM). Both motors start instantly. The set of normally open contacts of energized relay BR close and complete the circuit through evaporator blower (indoor) fan motor (IFM).
NOTE:** Once the compressor has started and then has stopped, it should not be started again until 5 minutes have elapsed.
The cooling cycle remains ‘‘on’’ until the room temperature drops to a point that is slightly below the cooling control setting of the room thermostat. At this point, the thermostat ‘‘breaks’’ the circuit between thermostat terminal R to  terminals Y and G. These open circuits de-energize contactor coil C and relay coil BR. The condenser and compressor motors stop. After a 30-second delay, the blower motor stops. The unit is in a ‘‘standby’’ condition, waiting for the next ‘‘call for cooling’’ from the room thermostat.

MAINTENANCE

To ensure continuing high performance, and to minimize the possibility of premature equipment failure, periodic maintenance must be performed on this equipment. This combination heating’ cooling unit should be inspected at least once each year by a qualified service person. To troubleshoot heating or cooling of units, refer to tables at the back of the book.
NOTE TO EQUIPMENT OWNER : Consult your local dealer about the availability of a maintenance contract.

WARNING

The ability to properly perform maintenance on this equipment requires certain expertise, mechanical skills, tools, and equipment. If you do net possess these. do nolallempt to perform any maintenance on this equipment other than those procedures recommended in the User’s Manual. FAILURE  TO HEED THIS WARNING COULD RESULT IN SPRI- OUS PSIURY AND POSSIBLE DAMAGE TO) THIS EQUIPMENT.
WARNING

Failure to follow these wamings could result in serious mjury or death:

1. Turn off gas supply, den tur off electrical power to the unit hectored performing any maintenance or service on the unit.
2. Use extreme caution when removing panels and parts. As with any mechanical equipment. serious injury can result from sharp edges. ete.
3. Never place anything combustible either on. or in contact with, the unit.
4. Should overheating occur. or the gas supply fin to shut off, shut off the extemal main manual gas valve to the unit, fen shut off the electrical supply.

CAUTION

Furors made when reconnecting wires may cause improper and dangerous operation. Label all wires prior to discannee- tion when servicing.
The minimum maintenance requirements for this equipment are as
follows:

1. Inspect air filter(s) each month. Clean or replace when necessary.
2. Inspect indoor coil. draw pan. and condensate drain cach cooling season tor cleanliness. Clean when necessary.
3. Inspect blower motor and wheel for cleanliness and check lubneation cach heating and cooling season. Clean when necessary. For first heating season, inspect blower wheel himonthly to determine proper cleaning frequency.
4. Check clecteal conncetions for tghiness and contrels for proper operation sach heating and cooling scason. Service when neeessary.
5. Check and inspect heating section before cach heating season. Clean and adjust when necessary.
6. Check flue hood and remove any obstructions if necessary.

AIR FILTER
IMPORTANT: Never operate the unit without a suitable air filter in the retum-air duct system. Always replace the filter with the same dimensional size and type as originally installed. See Tables 2 and 3 tor recommended filter sizes. Inspect air filter(s) at least once each month and replace (throwaway-type) or clean (eleanable-type} at least Wage during each heating and cooling season or whenever the filter(s) becomes slogged with dust and lint, EVAPORATOR BLOWER AND MOFOR
NOTE: All motors are pre-liberated, Do not attempt to lubricate these motors,
For longer life, operating economy, and continuing efficiency, clean accumulated dirt and grease fi’om the blower wheel and motor annually.
WARNING
Turn off the gas supply, then disconnect and tag electrical power to the unit before cleaning the blower motor and wheel. Failure to adhere to this warning could cause serious injury or death.
To clean the blower motor and wheel:

1. Remove and disassemble blower assembly as follows:
   a. Remove unit access panel.
   b. Disconnect motor lead fi’om blower relay (BR). Disconnect yellow lead from terminal L2 of the contactor.
   c. On all units, remove blower assembly fi’om unit. Remove screws securing blower to blower partition and slide assembly out. Be careful not to tear insulation in blower compartment.
   d. Ensure proper reassembly by marking blower wheel and motor in relation to blower housing bet`ore disassembly.
   e. Loosen setscrew(s) that secures wheel to motor shaft, remove screws that secure motor mount brackets to housing, and slide motor and motor mount out of housing.

2. Remove and clean blower wheel as follows:
   a. Ensure proper reassembly by marking wheel orientation.
   b. Lift wheel from housing. When handling and.or cleaning blower wheel, be sure not to disturb balance weights (clips) on blower wheel vanes.
   c. Remove caked-on dirt from wheel and housing with a brush. Remove lint and/or dirt accumulations from wheel and housing with vacuum cleaner, using soft brush attachment.
   Remove grease and oil with mild solvent.
   d. Reassemble wheel into housing.
   e. Reassemble motor into housing. Be sure setscrew(s) are tightened on motor shaft flats and not on round part of shaft.
   f. Reinstall unit access panel.

3. Restore electrical power, then gas supply to unit. Start unit and check l’or proper blower rotation and motor speeds during heating and cooling cycles.

FLUE GAS PASSAGEWAYS To inspect the flue collector box and upper areas of the heat exchanger:

Fig. 30–Blower Housing and Flue Collector Box

1. Remove the combustion blower wheel and motor assembly according to directions in Combustion-Air Blower section below.
2. Remove the 3 screws holding the blower housing to the flue collector box cover (see Fig. 30).
3. Remove the 12 screws holding the flue collector box cover (Fig. 30) to the heat exchanger assembly. Inspect the heat exchangers.
4. Clean all surfaces as required, using the wire brush.

COMBUSTION-AIR BLOWER Clean periodically to assure proper airflow and heating efficiency. Inspect blower wheel every fill and periodically during heating season. For the first heating season, inspect blower wheel bimonthly to determine proper cleaning frequency.
To inspect blower wheel, remove draft hood assembly. Shine a flashlight into opening to inspect wheeh If cleaning is required, remove motor and wheel as follows:

1. Remove unit access panel (See Fig. 29).
2. Remove the 7 screws that attach induced-draft motor mounting plate to blower housing (See Fig. 30).
3. Slide the motor and blower wheel assembly out of the blower housing (See Fig. 31). Clean the blower wheeh If additional cleaning is required, continue with Steps 4 and 5.
4. To remove blower, remove 2 setscrews (See Fig. 31).
5. To remove motor and cooling fan assembly, remove 4 screws that hold blower housing to mounting  plate.
6. To reinstall, reverse the procedure outlined above.
   LIMIT SWITCH Remove unit access panel. Limit switch is located on the blower partition.
   BURNER IGNITION Unit is equipped with a direct spark ignition 100% lockout system. Ignition module is located in the control box. Module contains a self- diagnostic LED. During servicing, refer to label diagram for LED interpretations. If lockout occurs, unit may be reset by either momentarily inten upting power supply to unit, or turning selector switch to OFF position at the thermostat. MAIN BURNERS At the beginning of each heating season,
   inspect for deterioration or blockage due to corrosion or other causes. Observe the main burner flames and adjust if necessary.

CAUTION
REMOVAL OF GAS TRAIN

1. Shut off manual gas valve.
2. Shut off power to unit.
3. Remove unit access panel (See Fig. 29).
4. Disconnect gas piping at unit gas valve.
5. Remove wires connected to gas valve. Mark each wire.
6. Remove ignitor and sensor wires at the ignitor module.
7. Remove the mounting screw that attaches the burner rack to the basepan (See Fig. 30).
8. Slide the burner rack out of the unit (See Figs. 30 and 32).
9. To reinstall, reverse the procedure outlined above.

CONDENSER COIL, EVAPORATOR COIL, AND CONDEN- SATE DRAIN PAN — Inspect the condenser coil, evaporator coil, and condensate drain pan at least once each year. The coils are easily cleaned when dry: therefore, spect and clean the coils either before or after each cooling season. Remove all obstructions, meluding weeds and shrubs, that interfere with the airflow through the condenser coil. Straighten bent fins with a fin comb. If coated with dirt or lint, clean the coils with a vacuum cleaner, using the soft brush attachment. Be careful not to bend the fins. If coated with oil or grease, clean the coils with a mild detergent-and-water solution. Rinse coils with clear water, using a garden hose. Be careful not to splash water on motors, insulation, wiring, or air filter(s). For best results, spray condenser coil fins from inside to outside the unit. On units with an outer and mner condenser coil, be sure to clean between the coils. Be sure to flush all dirt and debris from the unit base. Inspect the drain pan and condensate drain line when inspecting the coils. Clean the drain pan and condensate drain by removing all foreign matter from the pan. Flush the pan and drain tube with clear water. Do not splash water on the insulation, motor, wiring, or air filter(s). If the drain tube is restricted, clear it with a ‘plumbers snake’’ or similar probe device. Ensure that the auxiliary drain port above the drain tube is also clear.
CONDENSER FAN
CAUTION
Keep the condenser fan free from all obstructions to ensure proper cooling operation. Never place articles on top of the unit. Damage to unit may result.

1. Remove 6 screws holding condenser grille and motor to top cover.
2. Turn motor/grille assembly upside down on top cover to expose the fan blade.
3. Inspect the tan blades for cracks or bends.
4. If tan needs to be removed, loosen the setscrew and slide the time off the motor shaft.
5. When replacing fan blade, position blade so that the hub is 1/8 in. away from the motor end (1/8 in. of motor shaft will be visible).
6. Ensure that setscrew engages the flat area on the motor shaft when tightening.
7. Replace grille.

ELECTRICAL CONTROLS AND WIRING Inspect and check the electrical controls and wiring annually. Be sure to turn off’ Ne gas supply, and then the electrical pore to the unit.
Remove access panel to locate all the electrical controls and wiring. Check all electrical connections for tightness. Tighten all screw connections.
If any smokey or burned connections are noticed, disassemble the connection, clean all the parts, restrip the wire end and reassemble the connection properly and securely. After inspecting the electrical controls and wiring, replace the access panel. Start the unit, and obsel’e at least one complete heating cycle and one complete cooling cycle to ensure proper operation.
If discrepancies are observed in either or both operating cycles, or if a suspected malfunction has occun’ed, check each electrical component with the proper electrical instrumentation. Refer to the unit wiring label when making these checkouts.
NOTE: Refer to the heating and or cooling sequence of operation in this publication as an aid in determining proper control operation.
REFRIGERANT CIRCUIT Inspect all refrigerant tubing con- nections and the unit base for oil accumulations annually. Detect- ing oil generally indicates a refrigerant leak. If oil is detected or if low cooling performance is suspected, leak-test all refrigerant tubing using an electronic leak-detector, halide torch, or liquid-soap solution. If a refrigerant leak is detected, refer to Check for Refrigerant Leaks section on page 13. If no refrigerant leaks are found and low cooling performance is suspected, refer to Checking and Adjusting Refrigerant Charge section on page 20.  EVAPORATOR AIRFLOW The heating and/or cooling air- flow does not require checking unless improper performance is suspected. If a problem exists, be sure that all supply- and return-air g141les are open and free flam obstructions, and that the air filter is clean. When necessary, refer to Indoor Airflow and Airflow Adjustments section on page 20 to check the system airflow. METERING DEVICE ACCURATOR: PISTON This meter- ing device is a fixed orifice and is contained in the brass hex-body in the liquid line. PRESSURE SWITCHES Pressure switches are protective de- vices wired into control circuit (low voltage). They shut off compressor if abnormally high or low pressures are present in the refrigeration circuit. These pressure switches are specifically designed to operate with Puron (R-410A) systems. R-22 pressure switches must not be used as replacements for the Puron (R- 410A) air conditioner. LOSS OF CHARGE/LOW- PRESSURE SWITCH (AIR CONDI- TIONER ONLY) This switch is located on the liquid line and protects against low suction pressures caused by such events as loss of charge, low airflow across indoor coil, dirty filters, etc. It opens on a pressure drop at about 20 psig. If system pressure is above this, switch should be closed.
To check switch:

1. Turn off gas and then all power to unit.
2. Disconnect leads on switch.
3. Apply ohmmeter leads across switch. You should have con- tinuity on a good switch.

NOTE: Because these switches are attached to refrigeration  system under pressure, it is not advisable to remove this device for troubleshooting unless you are reasonably certain that a problem exists. If switch must be removed, remove and recover all system charge so that pressure gages read 0 psi. Never open system without breaking vacuum with dry nitrogen. HIGH-PRESSURE SWITCH The high-pressure switch is lo- cated in the discharge line and protects against excessive con- denser coil pressure. It opens at 610 psig. High pressure may be caused by a dirty condenser coil, flfiled tim motor, or condenser air recirculation.
To check switch:

1. Turn off gas and then all power to unit.
2. Disconnect leads on switch.
3. Apply ohmmeter leads across switch. You should have con- tinuity on a good switch.

COPELAND SCROLL COMPRESSOR  (PURON REFRIGER- ANT
The compressor used in this product is specifically designed to operate with Puron (R-410A) refrigerant and cannot be interchanged.
The compressor 1s an electrical (as well as mechanical) device.
Exercise extreme caution when working near compressors. Power should be shut off, if possible, for most troubleshooting tech- inquest. Refrigerants present additional safety hazards.
WARNING Wear safety glasses and gloves when handling refrigerants. Failure to follow this warning can cause a fire, serious mjury, or death.
The scroll compressor pumps refrigerant throughout the system by the interaction of a stationary and an orbiting scroll. The scroll compressor has no dynamic suction or discharge valves, and it is more tolerant of stresses caused by debris. liquid slugging. and flooded starts. The compressor is equipped with an anti-rotational device and an internal pressure relief port. The anti-rotational device prevents the scroll from turning backwards and replaces the need for a cycle protector. The pressure relief port is a safety device, designed to protect against extreme high pressure. the relief port has an operating range between 550 and 625 psi differential pressure.
The Copeland scroll compressor uses Mobil 3MA POE oil. This is the only oil allowed for oil recharge. REFRIGERANT —
CAUTION
This system uses Puron® (R-410A) refrigerant which has higher operating pressures than R-2? and other refrigerants.
No other refrigerant may be used in this system. Gage set, hoses, and recovery system must be designed to handle Puron. If you are unsure consult the equipment manufacturer. Failure to use Puron compatible servicing equipment or replacement components may result in property damage or immure.
COMPRESSOR OIL — The compressor in this system uses a polyester (POE) oil, Mobil 3MA POE. This oil is extremely hygroscopic, meaning it absorbs water readily. POE oils can absorb 15 times as much water as other oils designed for HCFC and CFC refrigerants. Take all necessary precautions to avoid exposure of the oil to the atmosphere.
SERVICING SYSTEMS ON ROOFS WITH SYNTHETIC MATERIALS POE (polyolester) compressor lubricants are known to cause long term damage to some synthetic roofing materials. Exposure, even if immediately cleaned up, may cause embrittle- ment (leading to cracking) to occur in one year or more. When performing any service that may risk exposure of compressor oil to the roof, take appropriate precautions to protect roofing. Procedures which risk oil leakage include, but are not limited to, compressor replacement, repairing refrigerant leaks, replacing refrigerant components such as filter drier, pressure switch, me- tering device, coil, accumulator, or reversing valve. SYNTHETIC ROOF PRECAUTIONARY PROCEDURE:

1. Cover extended roof working area with an impermeable polyethylene (plastic) drip cloth or tarp. Cover an approximate i0 x 10 ft. area.
2. Cover area in front of the unit service panel with a terry cloth shop towel to absorb lubricant spills and prevent run-offs, and protect drop cloth fiom tears caused by tools or components.
3. Place terry cloth shop towel inside unit immediately under component(s) to be serviced and prevent lubricant run-offs through the louvered openings in the base pan.
4. Perform required service.
5. Remove and dispose of any oil contaminated material per local codes.

LIQUID LINE FILTER DRIER The filter drier is specifically designed to operate with Puron. Use only fiaetory-authorized components.
Filter drier nmst be replaced whenever the refrigerant system is opened. When removing a filter drier, use a tubing cutter to cut the ierfiom the system. Do not unsweat a filter drier from the system. Heat from unseating will release moisture and contaminants fiomier into system.
PURON (R-410A) REFRIGERANT CHARGING Refer to unit information plate and charging chart. Some R-410A refrigerant cylinders contain a dip tube to allow liquid refrigerant to flow from cylinder in upright position. For cylinders equipped with a clip tube, charge Puron units with cylinder in upright position and a commercial metering device in manitbld hose. Charge refiigerant into suction-line.
AIR CONDITIONER WITH PURON® (R-410A)—QUICK REFERENCE GUIDE
Puron refrigerant operates at 50°0-70% higher pressures than R-22. Be sure that servicing equipment and replacement components are designed to operate with Puron.

• Puron refrigerant cylinders are rose colored.
• Puron refrigerant cylinders manufactured prior to March 1, 1999, have a dip tube that allows liquid to flow out of cylinder in upright position. Cylinders manufactured March 1, 1999 and later DO NOF have a dip tube and MUST be positioned upside down to allow liquid to flow.
• Recovery cylinder service pressure rating must be 400 psig, DOT 4BA400 or DOT BW400.
• Puron systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose.
• Manifold sets should be 750 psig high-side und 200 psig low-side with 520 psig low-side retard.
• Use hoses with 750 psig service pressure rating.
• Teak detectors should be designed to detect HFC refrigerant.
• Puron, as with other HFCs, is only compatible with POF oils.
• Vacuum pumps will not remove moisture tromp oil.
• Only use factory specified liquid-line filter driers with rated working pressures no less than 600 psig.
• Do not install a suction-line filter drier in liquid-line.
• POE oils absorb moisture rapidly. De not expose oil to atmosphere.
• POE oils may cause damage to certain plastics and roofing materials.
• Wrap all filter driers and service valves with wet cloth when brazing.
• A Puron liquid-line filter drier is required on every unit.
• Do not use an R-22 TRV.
• Never open system to atmosphere while it is under a vacuum.
• When system must be opened for service, break vacuum with dry nitrogen and replace filter driers.
• Always replace filter drier after opening system for service.
• Do not vent Puron into the atmosphere.
• Observe all warnings, cautions, and bold text.
• Do not leave Puron suction fine driers in place for more than 72 hours.

Table 10

Troubleshooting – Cooling

Table 11–Troubleshooting — Heating

SYMPTOM| CAUSE|

REMEDY

---|---|---
Burners will not ignite.| Water in gas line| Drain. Install drip leg.
No power to furnace| Check power supply fuses, wiring, or circuit breaker.
Miswired or loose connections| Check all wiring and wirenut connections.
Burned-out heat anticipator in thermostat| Replace thermostat.
Broken thermostat wire| Run continuity check. Replace wire if necessary.
Misaligned spark electrodes| Check flame ignition and sense electrode posi- tioning. Adjust as necessary
No gas at main burners| 1. Check gas line for air. Purge as necessary.
NOTE: After purging gas line of air, wait at least 5 minutes for any gas to dissipate before at- tempting to light unit.
2. Check gas valve.
Inadequate heating,| Dirty air filter| Clean or replace filter as incessant
Gas input to furnace too low| check gas pressure at manifold. Match with that on unit nameplate.
Unit undersized for application| Replace with proper unit or add additional unit.
Restricted airflow| Clean or replace filter. Remove any restriction.
Blower speed too low| Use faster speed tap if available, or install alter-Use motor.
Limit switch cycles main burners| Check rotation of blower, thermostat heat anticipator settings, and temperature rise of unit. Ad- just as necessary.
Poor flame. characteristics| Incomplete combustion results in: Aldehyde odors; carbon monoxide, sooting flame, floating flame| 1. Tighten all screws around burlier compart- ments.
2. Cracked heat exchanger. Replace
3. Unit overtired. Reduce input (change orifices or adjust gas line or manifold pressure).
4. Check burner alignment.

Table 12–LED Troubleshooting-Error Code

SYMPTOM| CAUSE|

REMEDY

---|---|---
Hardware failure. (LED OFF)| Loss of power to control module (IGC)| Check 5 amp fuse on !GC, power to unit, 24-v circuit breaker, and transformer. Units without a 24-v circuit breaker have an internal overload in the 24-v transformer. If the overload trips, allow 20 minutes for automatic reset.
Fan ON/OFF delay modified. (LED/FLASH)| High limit switch opens during heat exchanger warm-up period before fan-on delay expires| Ensure unit is fired on rate and temperature rise is correct.
Limit switch opens within three minutes after blower-off delay timing in Heating mode| Ensure unit’s external static pressure is within application guidelines.
Limit switch fault. (LED 2 flashes)| High temperature limit switch is open| Check operation of indoor (evaporator) fan motor.
Ensure that the supply-air temperature rise is in
accordance with the range on the unit nameplate.
Flame sense fault. (LED 3 flashes)| The :GC sensed flame that should not be present| Reset unit. If problem persists, replace control board.
4 consecutive limit switch faults. (LED 4 flashes)| Inadequate airflow to unit| Check operation of indoor (evaporator) fan motor and that supply-air temperature rise agrees with range on unit nameplate information.
Ignition lockout. (LED 5 flashes)| Unit unsuccessfully attempted ignition for 15 min- utes| Check ignitor and flame sensor electrode spac- ing, gaps, etc. Ensure that flame sensor and igni- Lion wires are properly terminated. Verify that unit is obtaining proper amount of gas.
Induce-draft motor fault. (LED 6 flashes)| IGC does not sense that induced- draft motor is operating| Check for proper voltage. If motor is operating, check the speed sensor plug/IGC Terminal 32 connection. Proper connection;
PIN i — White,
PIN 2 — Red,
PIN 3 — Black.
Rollout switch fault. (LED 7 flashes)| Rollout switch has opened| Rollout switch will automatically reset, but !GC will continue to lockout unit. check gas valve op- eration ensure that induced-draft blower wheel is properly secured to motor shaft. Reset unit at unit disconnect.
Internal control fault. (LED 8 flashes)| Microprocessor has sensed an error in the soft- ware or hardware| If error code is not cleared by resetting unit power, replace the IGC.
Internal software fault. (LED 9 flashes)| Microprocessor has sensed an error in it’s redundant software comparison| If error code is not cleared by resetting unit power; replace the IGC.

CAUTION
If the IGC must be replaced, be sure to ground yourself to dissipate any electrical charge that may be present before handling new control board, the IGC is sensitive to static electricity and may be damaged if the necessary precautions are not taken.
IMPORTANT: Refer to Heating Troubleshooting hart for additional troubleshooting analysis.
LEGEND IGC Integrated Gas Unit Controller LED Light-Emitting Diode

START-UP CHECKLIST
(Remove and Store in Job File)
I. PRELIMINARY INFORMATION
MODEL NO.:———————————-
DATE:————————-
SERIAL NO.:———————-
TECHNICIAN:————
II. PRE-START-[ P (Insert checkmark in box as each item is completed)
( ) VERIFY THAT ALL PACKING MATERIALS HAVE BEEN REMOVED FROM UNIT
( ) VERIFY THAT CONDENSATE CONNECTION IS INSTALLED PER INSTALLATION INSTRUCTIONS
( ) CHECK ALL ELECTRICAL CONNECTIONS AND TERMINALS FOR TIGHTNESS
( ) CHECK GAS PIPING FOR LEAKS
( ) CHECK THAT INDOOR (EVAPORATOR) AIR FILTER IS CLEAN AND IN PLACE
( ) VERIFY THAT LE’;IT INSTALLATION IS LEVEL
( ) CHECK FAN” WHEEL, AND PROPELLER FOR LOCATION IN HOUSING/ORIFICE AND SETSCREW TIGHTNESS
IlL START-UP
ELECTRICAL
SUPPLY VOLTAGE L1-L2———————– L2-L3 ———————L3-L1
COMPRESSOR AMPS LI —————————-L2—————————–L3
INDOOR (EVAPORATOR) FAN AMPS———————————
TEMPERAT[ RES
OUTDOOR (CONDENSER) AIR TEMPERATURE——————————–
RETURN-AIR TEMPERATURE—————- DB——————DB —————-WB
COOLING SUPPLY AIR————————- DB ———————–WB
GAS HEAT SUPPLY AIR ——————-PRESSURES
GAS INLET PRESSURE———————
GAS MANIFOLD PRESSURE——————-
REFRIGERANT SUCTION ———————–REFRIGERANT DISCHARGE —————IN. WG ———–IN. WG
PSIG SUCTION LINE TEMP* ————–PSIG DISCHARGE TEMP
( ) VERIFY REFRIGERANT CHARGE USING CHARGING CHARTS
( ) VERIFY THAT THREE-PHASE SCROLL COMPRESSOR
IS ROTATING IN CORRECT DIRECTION.

• Measured at suction inletto compressor 1 Measured at liquid line leaving condenser.

Copyright 2000 CARRIER Corp. 7310 W. Morris St  indianapolis, IN 46231 48gplsi
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4 PC 101 Catalog No 534-755 Printed in U.S.A. Form 48GP-1SI Pg 32 3-00 Replaces: New Tab 16al 8a

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