Carrier FB4CNF Fan Coil Units Installation Guide

: September 10, 2024
: Carrier

FB4CNF Fan Coil Units

Product Information

Specifications:

Model: FB4CNF, FB4CNP, FX4D
Product Type: Fan Coil Units for R-410A Refrigerant
Sizes Available: 018 to 061

Product Usage Instructions

Installation:

Step 1 – Check Equipment:

Unpack the unit and move it to the final location. Inspect the
equipment for any damage before installation. If any damage is
found, file a claim with the shipping company.

Step 2 – Mount Unit:

The unit can be placed on the floor, hung from the ceiling or
wall. Ensure there is enough space for wiring, piping, and
servicing the unit. If installed over a finished ceiling or living
area, a secondary condensate pan may be required as per building
codes.

Step 3 – Air Ducts:

Connect the air ducts according to the unit’s specifications.
Ensure proper airflow for efficient operation.

Step 4 – Electrical Connections:

Make electrical connections following the provided guidelines.
Always turn off power before servicing the unit to avoid electrical
hazards.

Step 5 – Refrigerant Tubing Connection and Evacuation:

Connect the refrigerant tubing carefully and perform evacuation
procedures as instructed to ensure optimal performance.

Step 6 – Refrigerant Flow-Control Device:

Install and set up the refrigerant flow-control device according
to the manufacturer’s recommendations.

Step 7 – Condensate Drains:

Set up condensate drains to prevent water build-up and ensure
proper drainage.

Step 8 – Accessories:

If using any accessories, install them following the provided
instructions for compatibility and functionality.

Step 9 – Sequence of Operation:

Familiarize yourself with the sequence of operation to
understand how the unit functions and troubleshoot if needed.

Start-Up Procedures:

Follow the start-up procedures outlined in the manual to ensure
a smooth and safe operation of the unit.

Care and Maintenance:

Regular maintenance is essential for optimal performance. Refer
to the manual for care and maintenance instructions.

Airflow Performance Tables:

Refer to the airflow performance tables provided to understand
the unit’s airflow capabilities and adjust as needed.

FAQ:

Q: What should I do if I find damage to the unit during

installation?

A: If you find any damage to the unit during
installation, immediately file a claim with the shipping company to
address the issue.

Q: Is it necessary to install a secondary condensate pan under

the unit?

A: Depending on building codes and regulations
in your area, a secondary condensate pan may be required when
installing the unit over a finished ceiling or living area. Consult
local codes for specific requirements.

FB4CNF FB4CNP FX4D

FAN COIL UNITS FOR R-410A REFRIGERANT
SIZES 018 TO 061

Installation Instructions

NOTE: Read the entire instruction manual before starting the installation.
TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . 1
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
HEATER PACKAGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Step 1 — Check Equipment . . . . . . . . . . . . . . . . . . . . . . . . . 2
Step 2 — Mount Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Step 3 — Air Ducts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Step 4 — Electrical Connections . . . . . . . . . . . . . . . . . . . . . 4
Step 5 — Refrigerant Tubing Connection and Evacuation . . 7 Step 6 — Refrigerant Flow-Control Device . . . . . . . . . . . . . 7
Step 7 — Condensate Drains . . . . . . . . . . . . . . . . . . . . . . . . 7
Step 8 — Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Step 9 — Sequence of Operation . . . . . . . . . . . . . . . . . . . . . 8 START-UP PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . 9
CARE AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . 9
AIRFLOW PERFORMANCE TABLES . . . . . . . . . . . . . . . . . 9
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance, or use can cause explosion, fire, electrical shock, or other conditions which may cause death, personal injury or property damage. Consult a qualified installer, service agency, or your distributor or branch for information or assistance. The qualified installer or agency must use factory-authorized kits or accessories when modifying this product. Refer to the individual instructions packaged with kits or accessories when installing. Follow all safety codes. Wear safety glasses, protective clothing and work gloves. Have a fire extinguisher available. Read these instructions thoroughly and follow all warnings or cautions included in literature and attached to the unit. Consult local building codes and the current editions of the National Electrical Code (NEC) NFPA 70. In Canada, refer to the current editions of the Canadian Electrical Code CSA C22.1. Recognize safety information. This is the safety- alert symbol . When you see this symbol on the unit and in instruction manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and CAUTION. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies hazards which could result in personal injury or death. CAUTION is used to identify unsafe practices which may result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation.
! WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury or death.
Before installing or servicing unit, always turn off all power to unit. There may be more than one disconnect switch. Turn off accessory heater power if applicable. Lock out and tag switch with a suitable warning label.
! CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and wear appropriate protective clothing and gloves when handling parts.
INTRODUCTION
FB4C and FX4D models are R-410A Fan Coils designed for installation flexibility. These units leave the factory compliant with low leak requirements of less than 2% cabinet leakage rate at 0.5 inches W.C. and 1.4% cabinet leakage rate at 0.5 inches W.C. when tested in accordance with ASHRAE 193 standard. FB4CNF(018-048) uses a refrigerant piston metering device. A TXV is used on FB4CNP and FX4D(018-061). All these fan coils use a multi-tap ECM motor for efficiency. The units have be designed for upflow, downflow (kit required), and horizontal orientations, including manufactured and mobile home applications. These units require a field supplied air filter, and are designed specifically for R-410A refrigerant air conditioners and heat pumps as shipped. These units are available for systems of 18,000 through 60,000 BTUh nominal cooling capacity. Factory- authorized, field – installed electric heater packages are available in sizes 5 through 30kW. See Product Data literature for all available accessory kits.

HEATER PACKAGES

This unit may or may not be equipped with an electric heater package. For units not equipped with factory-installed heat, a factory-approved, field- installed, UL listed heater package is available from your equipment supplier. See unit rating plate for a list of factory-approved heaters. Heaters that are not factory approved could cause damage which would not be covered under the equipment warranty. If fan coil contains a factory-installed heater package, minimum circuit ampacity (MCA) and maximum fuse/breaker may be different than units with a same size field-installed accessory heater. The differences is not an error and is due to calculation difference per UL guidelines.
INSTALLATION

Step 1 — Check Equipment

Unpack unit and move to final location. Remove carton taking care not to damage unit. Inspect equipment for damage prior to installation. File claim with shipping company if shipment is damaged or incomplete.
NOTE: If the door gasket is damaged or missing, the unit may not meet the ASHRAE 193 standard for cabinet air leakage. Contact your supplier and order kit #344994-751.

Locate unit rating plate which contains proper installation information. Check rating plate to be sure unit matches job specifications.
Step 2 — Mount Unit

Unit can stand or lie on floor, or hang from ceiling or wall. Allow space for wiring, piping, and servicing unit.
IMPORTANT: When unit is installed over a finished ceiling and/or living area, building codes may require a field-supplied secondary condensate pan to be installed under the entire unit. Some localities may allow as an alternative, the running of a separate, secondary condensate line. Consult local codes for additional restrictions or precautions.

NOTE: Nuisance sweating may occur if the unit is installed in a high humidity environment with low airflow.

A. Upflow Installation

If return air is to be ducted through a floor, set unit on floor over opening and use 1/8 to 1/4-in (3 to 6 mm) thick fireproof resilient gasket between duct, unit, and floor.

Side return is a field option on slope coil models. Cut opening per dimensions. (See Fig. 1.) A field-supplied bottom closure is required.

POWER ENTRY OPTIONS
018 – 048 21″ (533 mm) FRONT SERVICE 060 – 060 24″ (610mm) CLEARANCE
A COIL UNITS

FIELD SUPPLIED SUPPLY DUCT
LOW VOLT ENTRY OPTIONS

UNIT
018, 024 025 – 030
036

A 12″ (305 mm) 17″ (432 mm) 19″ (483 mm)

UPFLOW/DOWNFLOW SECONDARY DRAIN
UPFLOW/DOWNFLOW PRIMARY DRAIN
UPFLOW/DOWNFLOW SECONDARY DRAIN

1.5″ (38 mm) 19″ (483 mm)

2.5″ A
(64 mm)

FIELD MODIFIED SIDE RETURN LOCATION FOR SLOPE COIL UNITS ONLY

UPFLOW/DOWNFLOW PRIMARY DRAIN

FIELD SUPPLIED RETURN PLENUM

A07565
Fig. 1 – Slope Coil Unit in Upflow Application

B. Downflow Installation In this application, field conversion of the evaporator is required using accessory downflow kit along with an accessory base kit. Use fireproof resilient gasket, 1/8 to 1/4-in (3 to 6 mm) thick, between duct, unit, and floor.
! CAUTION
UNIT OR PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or property damage.
The conversion of the fan coil to downflow requires special procedures for the condensate drains on both A-coil and slope units. The vertical drains have an overflow hole between the primary and secondary drain holes. This hole is plugged for all applications except downflow, but must be used for downflow. During the conversion process, remove the plastic cap covering the vertical drains only and discard. Remove the plug from the overflow hole and discard. At completion of the downflow installation, caulk around the vertical pan fitting to door joint to retain the low air leak performance of the unit.
NOTE: To convert units for downflow applications, refer to Installation Instructions supplied with kit for proper installation. For slope fan coils, use kit Part No. KFADC0201SLP. For A-coils, use kit Part No. KFADC0401ACL. Use fireproof resilient gasket, 1/8 to 1/4-in (3 to 6 mm) thick, between duct, unit, and floor. NOTE: Gasket kit number KFAHD0101SLP is also required for all downflow applications to maintain low air leak/low sweat performance. C. Horizontal Installation Units must not be installed with access panels facing up or down. All other units are factory built for horizontal left installation. (See Fig. 2 and 3.) When suspending unit from ceiling, dimples in casing indicate suitable location of screws for mounting metal support straps. (See Fig. 2.) For horizontal applications having high return static and humid return air, the Water Management Kit, KFAHC0125AAA, may need to be used to assist in water management.
! CAUTION
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or property damage.
For optimum condensate drainage performance in horizontal installations, unit should be leveled along its length and width.
A-COIL HORIZONTAL LEFT

LOW VOLT ENTRY OPTIONS

FIELD SUPPLIED HANGING STRAPS
UNIT

SECONDARY DRAIN

PRIMARY DRAIN

018-048 21″ (533 mm) 060-060 24″ (610 mm) FRONT SERVICE CLEARANCE (FULL FACE OF UNIT)

1.75″ (44 mm) FILTER ACCESS CLEARANCE

POWER ENTRY OPTIONS

SECONDARY DRAIN

PRIMARY DRAIN

A07566
Fig. 2 – Slope Coil Unit in Horizontal Left Application

2

A
FACTORY SHIPPED HORIZONTAL LEFT
APPLICATION
B C

COIL BRACKET
COIL SUPPORT
RAIL
DRAIN PAN SUPPORT BRACKET
COIL BRACKET

HORIZONTAL DRAIN PAN

AIR SEAL ASSEMBLY

PRIMARY DRAIN HORIZONTAL LEFT

REFRIGERANT CONNECTIONS

SECONDARY DRAIN HORIZONTAL LEFT

A00072
Fig. 3 – A-Coil in Horizontal Left Application

NOTE: Modular units can be disassembled and components moved separately to installation area for reassembly. This process accommodates small scuttle holes and limiting entrances to installation sites. (See Fig. 4 .)

2 SCREWS

BLOWER BOX 2 SCREWS

REAR CORNER BRACKET

COIL BOX

2 SCREWS

A95293
Fig. 4 – Removal of Brackets on Modular Units Horizontal Right Conversion of Units With Slope Coils
NOTE: Gasket kit number KFAHD0101SLP is required for horizontal slope coil conversion to maintain low air leak/low sweat performance.
1. Remove blower and coil access panel and fitting panel. (See Fig. 5.)
2. Remove coil mounting screw securing coil assembly to right side casing flange.
3. Remove coil assembly.
4. Lay fan coil unit on its right side and reinstall coil assembly with condensate pan down. (See Fig. 5.)
5. Attach coil to casing flange using coil mounting screw previously removed.
6. Make sure the pan cap in the fitting door is properly seated on the fitting door to retain the low air leak rating of the unit.
7. Add gaskets from kit KFAHD per kit instructions.
8. Align holes with tubing connections and condensate pan connections, and reinstall access panels and fitting panel.
Make sure liquid and suction tube grommets are in place to prevent air leaks and cabinet sweating. Install after brazing.

COIL MOUNTING SCREW

BLOWER ASSEMBLY

COIL SUPPORT
RAIL

SLOPE COIL SKI

DRAINPAN

REFRIGERANT CONNECTIONS

PRIMARY DRAIN

SECONDARY DRAIN

A03001
Fig. 5 – Conversion for Horizontal Right Applications

Horizontal Right Conversion of Units With A-Coils 1. Remove blower and coil access panels. (See Fig. 6.)

REFRIGERANT CONNECTIONS
COIL SUPPORT
RAIL
COIL BRACKET

AIR SEAL ASSEMBLY

A
HORIZONTAL RIGHT
APPLICATION
B C

DRAIN PAN SUPPORT BRACKET
COIL SUPPORT
RAIL
COIL BRACKET
HORIZONTAL DRAIN PAN
PRIMARY DRAIN HORIZONTAL RIGHT SECONDARY DRAIN HORIZONTAL RIGHT
A00071
Fig. 6 – Conversion for Horizontal Right Applications Using A-Coil
2. Remove metal clip securing fitting panel to condensate pan. Remove fitting panel.
3. Remove 2 snap-in clips securing A-coil in unit.
4. Slide coil and pan assembly out of unit.
5. Remove horizontal drain pan support bracket from coil support rail on left side of unit and reinstall on coil support rail on right side of unit. (See Fig. 7.)
DRAIN PAN SUPPORT BRACKET

Fig. 7 – Drain Pan Support Bracket

A07571

3

6. Convert air-seal assembly for horizontal right. a. Remove air-seal assembly from coil by removing 4 screws. (See Fig. 6.)
b. Remove air splitter (B) from coil seal assembly by removing 3 screws. (See Fig. 3-factory shipped inset.)
c. Remove filter plate (A) and install air splitter (B) in place of filter plate.
d. Install filter plate (A) as shown in horizontal right application.
e. Remove condensate troughs (C) and install on opposite tube sheets.
f. Install hose onto plastic spout.
7. Install horizontal pan on right side of coil assembly.
8. Slide coil assembly into casing. Be sure coil bracket on each corner of vertical pan engages coil support rails.
9. Reinstall 2 snap-in clips to correctly position and secure coil assembly in unit. Be sure clip with large offsets is used on right side of unit to secure horizontal pan.
10. Remove two oval fitting caps from the left side of the coil door and fitting panel.
11. Remove insulation knockouts on right side of coil access panel.
12. Remove 2 oval coil access panel plugs and reinstall into holes on left side of coil access panel and fitting panel.
13. Install condensate pan fitting caps (from item 10) in the right side of the coil door making sure that the cap snaps and seats cleanly on the back side of the coil door. Make sure no insulation interferes with seating of the cap.
14. Reinstall access fitting panels, aligning holes with tubing connections and condensate pan connections. Be sure to reinstall metal clip between fitting panel and vertical condensate pan.
Make sure liquid and suction tube grommets are in place to prevent air leaks and cabinet sweating.
D. Manufactured and Mobile Home Housing Applications 1. Fan coil unit must be secured to the structure using field- supplied hardware. 2. Allow a minimum of 24-in (610 mm) clearance from access panels.
3. Recommended method of securing for typical applications:
a. If fan coil is away from wall, attach pipe strap to top of fan coil using no. 10 self-tapping screws. Angle strap down and away from back of fan coil, remove all slack, and fasten to wall stud of structure using 5/16-in. lag screws. Typical both sides of fan coil.

4″ (102mm) MAX
SECURE FAN COIL TO STRUCTURE UNIT AWAY FROM WALL PIPE STRAP (TYPICAL BOTH SIDES)
OR
UNIT AGAINST WALL .125″ (3mm) MOUNTING BRACKET (TYPICAL BOTH SIDES)

DOWN FLOW BASE KIT (KFACB)
SECURE UNIT TO FLOOR ANGLE BRACKET OR PIPE STRAP

4″ (102mm) MAX

Fig. 8 – A-Coil

A07567

b. If fan coil is against wall, secure fan coil to wall stud using 1/8-in (3 mm) thick right-angle brackets. Attach brackets to fan coil using no. 10 self- tapping screws and to wall stud using 5/16-in. lag screws. (See Fig. 8.)

Step 3 — Air Ducts
Connect supply-air duct over the outside of 3/4-in (19 mm) flanges provided on supply-air opening. Secure duct to flange, using proper fasteners for type of duct used, and seal duct-to-unit joint. If return-air flanges are required, install factory-authorized accessory kit.

Use flexible connectors between ductwork and unit to prevent transmission of vibration. When electric heater is installed, use heat-resistant material for flexible connector between ductwork and unit at discharge connection. Ductwork passing through
unconditioned space must be insulated and covered with vapor barrier. Units equipped with 20-30kW electric heaters require a 1-in (25 mm) clearance to combustible materials for the first 36-in (914 mm) of supply duct.

Ductwork Acoustical Treatment Metal duct systems that do not have a 90_ elbow and 10-ft (3m) of main duct to first branch takeoff may require internal acoustical insulation lining. As an alternative, fibrous ductwork may be used if constructed and installed in accordance with the latest edition of SMACNA construction standard on fibrous glass ducts. Both acoustical lining and fibrous ductwork shall comply with National Fire Protection Association as tested by UL Standard 181 for Class 1 air ducts.

Step 4 — Electrical Connections

FB4C units from the factory protect the low voltage circuit with a 3 amp automotive type fuse in-line on the wire harness and Does Not contain a circuit board. Motor speeds and time delay function are built into the motor (see section E for clarification). When a factory-approved accessory control package has been installed, check all factory wiring per unit wiring diagram and inspect factory wiring connections to be sure none were loosened in transit or installation. If a different control package is required, see unit rating plate.

4

! CAUTION
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or property damage.
If a disconnect switch is to be mounted on unit, select a location where drill or fastener will not contact electrical or refrigerant components.
Before proceeding with electrical connections, make certain that supply voltage, frequency, phase, and ampacity are as specified on the unit rating plate. See unit wiring label for proper field high- and low-voltage wiring. Make all electrical connections in accordance with the NEC and any local codes or ordinances that may apply. Use copper wire only. The unit must have a separate branch electric circuit with a field-supplied disconnect switch located within sight from, and readily accessible from, the unit. On units with a factory-installed disconnect with pull-out removed, service and maintenance can be safely performed on only the load side of the control package.
! WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Field wires on the line side of the disconnect found in the fan coil unit remain live, even when the pull-out is removed. Service and maintenance to incoming wiring cannot be performed until the main disconnect switch (remote to the unit) is turned off.
A. Line Voltage Connections If unit will contain accessory electric heater, remove and discard power plug from fan coil and connect male plug from heater to female plug from unit wiring harness. (See Electric Heater Installation Instructions.) For units without electric heater:
1. Connect 208/230v power leads from field disconnect to yellow and black stripped leads.
2. Connect ground wire to unit ground lug. NOTE: Units installed without electric heat should have a field-supplied sheet metal block-off plate covering the heater opening. This will reduce air leakage and formation of exterior condensation. B. 24-v Control System Connection To Unit Wire low voltage in accordance with wiring label on the blower. (See Fig. 9 through 12.) Use no. 18 AWG color-coded, insulated (35_C minimum) wire to make the low-voltage connections between the thermostat, the unit, and the outdoor equipment. If the thermostat is located more than 100-ft (30 m) from the unit (as measured along the low-voltage wire), use no. 16 AWG color-coded, insulated (35_C minimum) wire. All wiring must be NEC Class 1 and must be separated from incoming power leads.

THERMOSTAT

FAN COIL (CONTROL)

R

RED

R

G

GRY G

WHT

W

WHT

W2

BLU W3

VIO E

BRN C

Y

AIR COND. C Y

Fig. 9 – Wiring Layout Air Conditioning Unit

(Cooling Only)

THERMOSTAT

FAN COIL (CONTROL)

R

RED

R

G

GRY G

WHT

W WHT

W2

BLU W3

VIO E

BRN C

AIR COND.

C

Y

A94058

Fig. 10 – Wiring Layout Air Conditioning Unit (Cooling and 1-Stage Heat)

THERMOSTAT R G

FAN COIL (CONTROL)
RED R GRY G

HEAT PUMP (CONTROL)
R

C

BRN C

C

W2

WHT BLU

W2 W3

E

VIO E

L

W2

A94059

O

Y

A94060
Fig. 11 – Wiring Layout Heat Pump Unit (Cooling and 2-Stage Heat with No Outdoor Thermostat)

THERMOSTAT

FAN COIL (CONTROL)

HEAT PUMP (CONTROL)

R

G

C

W2

W3

E

L

ODTS

O

Y

A03088
Fig. 12 – Wiring Layout Heat Pump Unit (Cooling and 2-Stage Heat for Manufactured Housing)

5

Refer to outdoor unit wiring instructions for any additional wiring procedure recommendations.
Transformer Information Transformer is factory-wired for 230v operation. For 208v applications, disconnect the black wire from the 230v terminal on transformer and connect it to the 208v terminal. (See Fig. 13.)
SECONDARY

BRN RED

C 208 230

YEL BLK
PRIMARY

Fig. 13 – Transformer Connections

A05182

Heater Staging

If electric heat staging is required, a multi-stage heating room thermostat is required. Consult your equipment supplier for a suitable thermostat.

C. Manufactured Housing

In manufactured housing applications, the Code of Federal Regulations, Title 24, Chapter XX, Part 3280.714 requires that supplemental electric heat be locked out at outdoor temperatures above 40_F (4_C), except for a heat pump defrost cycle. Refer to Fig. 12 for typical low voltage wiring with outdoor thermostat.

D. Ground Connections

! WARNING

ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
According to NEC, ANSI/NFPA 70, and local codes, the cabinet must have an uninterrupted or unbroken ground to minimize personal injury if an electrical fault should occur. The ground may consist of electrical wire or metal conduit when installed in accordance with existing electrical codes. If conduit connection uses reducing washers, a separate ground wire must be used.

NOTE: Use UL-listed conduit and conduit connector for connecting supply wire(s) to unit to obtain proper grounding. Grounding may also be accomplished by using grounding lugs provided in control box.
E. Minimum CFM and Motor Speed Selection
The fan speed selection is done at the motor connector. Units with or without electric heaters require a minimum CFM. Refer to the unit wiring label to ensure that the fan speed selected is not lower than the minimum fan speed indicated.

Tap 1

Low

90 sec off delay

Tap 2

Medium

90 sec off delay

Tap 3

High

90 sec off delay

Tap 4

Electric heat

0 sec off delay

Tap 5

Max

0 sec off delay

electric heat airflow is same CFM as Tap 3, except 0 sec off delay high static applications, see airflow tables for max airflow

To change motor speeds disconnect the BLUE fan lead from motor connector terminal #2 (factory default position) and move to desired speed-tap; 1, 2, 3, or 5.
Speed-taps 1, 2, and 3 have a 90 second blower off time delay pre-programmed into the motor. Speed-tap 4 is used for electric heat only (with 0 second blower time delay) and the WHITE wire should remain on tap 4. Speed-tap 5 is used for high static applications, but has a 0 second blower time delay pre- programmed into the motor. See Airflow Performance tables for actual CFM. Also, see Fig. 14 for motor speed selection location.
NOTE: In low static applications, lower motor speed tap should be used to reduce possibility of water being blown off coil.

1 2 3 4 5

Speed Taps may be located on motor, or on plug close to motor.

1 2 3 4 5

C LG N

Fig. 14 – Motor Speed Selection

A11048

Step 5 — Refrigerant Tubing Connection and Evacuation
Use accessory tubing package or field-supplied tubing of refrigerant grade. Suction tube must be insulated. Do not use damaged, dirty, or contaminated tubing because it may plug refrigerant flow-control device. ALWAYS evacuate the coil and field-supplied tubing to 500 microns before opening outdoor unit service valves.

6

! CAUTION

PRODUCT DAMAGE HAZARD
Failure to follow this caution may result in product or property damage.
A brazing shield MUST be used when tubing sets are being brazed to the unit connections to prevent damage to the unit surface and condensate pan fitting caps.
Units have sweat suction and liquid tube connections. Make suction tube connection first.
1. Cut tubing to correct length. 2. Insert tube into sweat connection on unit until it bottoms. 3. Braze connection using silver bearing or non-silver bearing
brazing materials. Do not use solder (materials which melt below 800_F / 427_C). Consult local code requirements. 4. Evacuate coil and tubing system to 500 microns using deep vacuum method.
! CAUTION

PRODUCT DAMAGE HAZARD
Failure to follow this caution may result in product or property damage. Wrap a wet cloth around rear of fitting to prevent damage to piston assembly or TXV and factory-made joints.

Step 6 — Refrigerant Flow-Control Device
FB4CNF units contain a factory installed piston with Teflon ring for sizes 018 thru 048 only. The FB4CNP and FX4D(018-061) size units come equipped with a R-410A refrigerant TXV. If a piston replacement is required, check piston size shown on indoor unit rating plate to see if it matches required outdoor piston size. The outdoor piston size will be found on the outdoor unit rating
plate, product data or installation instructions depending on the model. If the fan coil piston does not match, replace indoor piston
with correct outdoor piston. With some outdoor units a piston is shipped with outdoor unit; if no piston is shipped with the outdoor unit one can be ordered from Replacement Components. When changing piston, use a back-up wrench. (See Fig. 15). Hand tighten hex nut, then tighten with wrench 1/2 turn. Do not exceed 30 ft-lbs.

BRASS HEX NUT

TEFLON SEAL

DISTRIBUTOR

TEFLON RING

PISTON
FLOW IN COOLING PISTON RETAINER

BRASS HEX BODY

NOTE: The indoor piston contains a Teflon ring (or seal) which is used to seat against the inside of distributor body, and must be installed properly to ensure proper seating in the direction for cooling operation.
Always use outdoor units designed to match indoor fan coil applications.
! CAUTION
PRODUCT OPERATION HAZARD
Failure to follow this caution may result in improper product operation. If using a TXV in conjunction with a single-phase reciprocating compressor, a compressor start capacitor and relay are required. Consult outdoor unit pre- sale literature for start assist kit part number.
Step 7 — Condensate Drains
To connect drains, the cap openings must be removed. Use a knife to start the opening near the tab and using pliers, pull the tab to remove the disk. Clean the edge of the opening if necessary and install the condensate line. Finally caulk around the lines where they exit the fitting to retain the low leak rating of the unit.
! CAUTION
UNIT OR PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or property damage.
The conversion of the fan coil to downflow requires special procedures for the condensate drains on both A-coil and slope units. The vertical drains have an overflow hole between the primary and secondary drain holes. This hole is plugged for all applications except downflow, but must be used for downflow. During the conversion process, remove the plastic cap covering the vertical drains only and discard. Remove the plug from the overflow hole and discard. At completion of the downflow installation, caulk around the vertical pan fitting to door joint to retain the low air leak performance of the unit.
Units are equipped with primary and secondary 3/4-in. FPT drain connections. For proper condensate line installations see Fig. 1, 2, 3, 5 and 6. To prevent property damage and achieve optimum drainage performance, BOTH primary and secondary drain lines should be installed and include properly-sized condensate traps. (See Fig. 16 and 17.) Factory-approved condensate traps are available. It is recommended that PVC fittings be used on the plastic condensate pan. Finger-tighten plus 1-1/2 turns. Do not over-tighten. Use pipe dope.

UNIT

2″ MIN (51 mm)

STRAINER

2″ MIN (51 mm)

A09677
Fig. 15 – Refrigerant Flow – Control Device
7

Fig. 16 – Recommended Condensate Trap

A03002

PRIMARY TRAP REQUIRED (USE FACTORY KIT OR
FIELD-SUPPLIED TRAP OF SUFFICIENT DEPTH.
STANDARD P-TRAPS ARE NOT SUFFICIENT. SEE
FIGURE OF RECOMMENDED CONDENSATE TRAP)

FILTER ACCESS PANEL
SECONDARY DRAIN WITH APPROPRIATE TRAP REQUIRED (USE FACTORY KIT OR FIELD- SUPPLIED TRAP)

Fig. 17 – Condensate Trap and Unit

A03003

! CAUTION

PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or property damage.
Shallow running traps are inadequate and DO NOT allow proper condensate drainage. (See Fig. 18.)

DO NOT USE SHALLOW RUNNING TRAPS!

Fig. 18 – Insufficient Condensate Trap

A03013

NOTE: When connecting condensate drain lines, avoid blocking filter access panel, thus preventing filter removal. After connection, prime both primary and secondary condensate traps.

NOTE: If unit is located in or above a living space where damage may result from condensate overflow, a field-supplied, external condensate pan should be installed underneath the entire unit, and a secondary condensate line (with appropriate trap) should be run from the unit into the pan. Any condensate in this external condensate pan should be drained to a noticeable place. As an alternative to using an external condensate pan, some localities may allow the use of a separate 3/4-in (19 mm) condensate line (with appropriate trap) to a place where the condensate will be noticeable. The owner of the structure must be informed that when condensate flows from the secondary drain or external condensate pan, the unit requires servicing or water damage will occur.

Install traps in the condensate lines as close to the coil as possible. (See Fig. 17.) Make sure that the outlet of each trap is below its connection to the condensate pan to prevent condensate from overflowing the drain pan. Prime all traps, test for leaks, and insulate traps if located above a living area. Condensate drain lines

should be pitched downward at a minimum slope of 1-in (25 mm) for every 10-ft (3 m) of length. Consult local codes for additional restrictions or precautions.
Step 8 — Accessories
Humidifier
Connect humidifier and humidistat to fan coil unit as shown in Fig. 19 and Fig. 20. The cooling lockout relay is optional.
Step 9 — Sequence of Operation
A. Continuous Fan
Thermostat closes R to G. G energizes fan relay on PCB which completes circuit to indoor blower motor. When G is de-energized, there is a 90-sec delay before relay opens.
B. Cooling Mode
Thermostat energizes R to G, R to Y, and R to O (heat pump only). G energizes fan relay on PCB which completes circuit to indoor blower motor. When G is de- energized, there is a 90-sec delay before fan relay opens. C. Heat Pump Heating with Auxiliary Electric Heat
Thermostat energizes R to G, R to Y, and R to W. G energizes fan relay on PCB which completes circuit to indoor blower motor. W energizes electric heat relay(s) which completes circuit to heater element(s). When W is de-energized, electric heat relay(s) open, turning off heater elements. When G is de- energized there is a 90-sec delay before fan relay opens. D. Electric Heat or Emergency Heat Mode
Thermostat closes R to W. W energizes electric heat relay(s) which completes circuit to heater element(s). Blower motor is energized through normally closed contacts on fan relay. When W is de-energized, electric heat relay(s) opens.

THERMOSTAT

FAN COIL (CONTROL)

R

RED R

G

GRY G

C

BRN C

W2

WHT

WHT BLU

W2 W3

E

VIO E

L

HEAT PUMP (CONTROL)
R
C
W2

O

Y

FAN HUMIDIFIER 115V M

RELAY

HUMIDISTAT

A95294
Fig. 19 – Wiring Layout of Humidifier to Heat Pump

8

THERMOSTAT

FAN COIL (CONTROL)

R

RED

R

G

GRY G

WHT

W

WHT

W2

BLU W3

VIO E

BRN C

AIR COND.

C

Y FAN HUMIDIFIER

Y HUMIDISTAT

115V M

A95295
Fig. 20 – Wiring Layout of Humidifier to Fan Coil
With Electric Heat

START-UP PROCEDURES
Refer to outdoor unit Installation Instructions for system start-up instructions and refrigerant charging method details.
! CAUTION
UNIT COMPONENT HAZARD
Failure to follow this caution may result in product damage.
Never operate unit without a filter. Damage to blower motor or coil may result. Factory authorized filter kits must be used when locating the filter inside the unit. For those applications where access to an internal filter is impractical, a field-supplied filter must be installed in the return duct system.
CARE AND MAINTENANCE
To continue high performance and minimize possible equipment failure, it is essential that periodic maintenance be performed on this equipment. Consult your local dealer as to the proper frequency of maintenance contract. The ability to properly perform maintenance on this equipment requires certain mechanical skills and tools. If you do not possess these, contact your dealer for maintenance. The only consumer service recommended or required is filter replacement or cleaning on a monthly basis.

AIRFLOW PERFORMANCE TABLES

Table 1 Air Delivery Performance Correction Component Pressure Drop (in. wc) at Indicated Airflow (Dry to Wet Coil)

CFM

UNIT SIZE 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

018, 019 024 025
030, 031 036 037
042, 043 048 049 060 061

0.034 0.049 0.063 0.034 0.049 0.063 0.076 0.089 0.015 0.026 0.038 0.049 0.059
0.049 0.059 0.070 0.080 0.070 0.080 0.090 0.099 0.055 0.064 0.073 0.081 0.049 0.056 0.063 0.070 0.063 0.070 0.076 0.083 0.090 0.038 0.043 0.049 0.054 0.059 0.049 0.054 0.059 0.065 0.070 0.027 0.031 0.035 0.039 0.043

SIZE
018, 019 024 – 031 036-049 060, 061

400 0.020
–

Table 2 Factory-Installed Filter Static Pressure Drop (in. wc)

CFM

600

800

1000

1200

1400

1600

0.044 0.022
–

0.075 0.048
–

0.072 0.051
–

0.100 0.070
–

0.092 –

0.120 0.086

1800 –
0.152 0.105

2000 –
0.130

HEATER ELEMENTS
0 1 2 3 4

Table 3 Electric Heater Static Pressure Drop (in. wc)

Sizes 018 – 037

EXTERNAL STATIC

kW

PRESSURE

CORRECTION

HEATER ELEMENTS

Sizes 042 – 061

EXTERNAL STATIC

kW

PRESSURE

CORRECTION

0

+.02

0

+.04

3, 5

+.01

2

8, 10

+.02

8, 10

0

3

9, 15

0

9, 15

.02

4

20

.02

20

.04

6

18, 24, 30

.10

9

AIRFLOW PERFORMANCE TABLES (cont)

MODEL & SIZE FB4C 018
FB4C 024 / 025 FB4C 030 FB4C 036 FB4C 042 FB4C 048 FB4C 060 FB4C 061

BLOWER SPEED Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1

Table 4 FB4C Airflow Performance (CFM)

0.10

0.20

0.30

0.40

767 614 701 614 410 969 826 826 701 617 1108 1026 1026 909 825 1301 1227 1227 1087 1026 1560 1419 1419 1249 1242 1743 1669 1669 1452 1300 1897 1817 1817 1657 1443 2030 1811 1811 1665 1462

739 569 660 569 350 936 795 795 660 592 1090 1000 1000 873 795 1276 1191 1191 1062 1000 1544 1397 1397 1220 1205 1712 1634 1634 1413 1256 1867 1785 1785 1621 1412 1995 1775 1775 1632 1418

702 534 616 534 304 892 766 766 616 552 1065 969 969 842 757 1245 1169 1169 1030 969 1507 1358 1358 1184 1158 1679 1599 1599 1377 1221 1836 1757 1757 1589 1377 1961 1740 1740 1593 1371

669 486 581 486 261 835 743 743 581 507 1034 938 938 799 722 1218 1143 1143 1001 938 1464 1320 1320 1142 1110 1642 1564 1564 1339 1182 1808 1724 1724 1557 1332 1927 1703 1703 1556 1327

0.50
620 436 537 436 228 763 706 706 537 472 1009 899 899 762 674 1176 1105 1105 966 899 1424 1279 1279 1093 1069 1610 1531 1531 1308 1142 1774 1693 1693 1518 1286 1888 1664 1664 1507 1278

0.60
565 398 499 398 203 676 660 660 499 420 974 865 865 724 634 1121 1074 1074 930 865 1358 1239 1239 1052 1026 1574 1499 1499 1271 1101 1736 1655 1655 1474 1243 1842 1613 1613 1453 1228

– Shading – Airflow outside 450 cfm/ton. NOTES:
1. Airflow based upon dry coil at 230v with factory-approved filter and electric heater (2 element heater sizes 018 through 036, 3 element heater sizes 042 through 061).
2. For FB4C models, airflow at 208 volts is approximately the same as 230 volts because the multi-tap ECM motor is a constant torque motor. The torque doesn’t drop off at the speeds the motor operates.

3. To avoid potential for condensate blowing out of drain pan prior to making drain trap: Return static pressure must be less than 0.40 in. wc. Horizontal applications of 042 – 061 sizes must have supply static greater than 0.20 in. wc.
4. Airflow above 400 cfm/ton on 048-061 size could result in condensate blowing off coil or splashing out of drain pan.

10

AIRFLOW PERFORMANCE TABLES (cont)

MODEL & SIZE
FX4D 019 FX4D 025 FX4D 031 FX4D 037 FX4D 043 FX4D 049 FX4D 061

BLOWER SPEED Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1 Tap 5 Tap 4 Tap 3 Tap 2 Tap 1

Table 5 FX4D Airflow Performance (CFM)

EXTERNAL STATIC (in. wc)

0.10

0.20

0.30

0.40

776

745

696

660

683

644

589

548

683

644

589

548

631

563

500

443

625

524

457

417

956

920

891

851

825

795

757

722

825

795

757

722

726

695

635

598

631

563

500

443

1189

1151

1104

1050

1041

998

944

886

1041

998

944

886

924

876

817

752

779

693

628

571

1363

1332

1294

1253

1237

1206

1160

1121

1237

1206

1160

1121

1095

1058

1007

951

1014

885

773

673

1519

1490

1454

1419

1437

1403

1366

1333

1437

1403

1366

1333

1257

1226

1191

1141

1237

1206

1160

1121

1757

1725

1693

1653

1664

1626

1593

1552

1664

1626

1593

1552

1459

1420

1379

1336

1301

1241

1195

1150

2030

1995

1961

1927

1811

1775

1740

1703

1811

1775

1740

1703

1665

1632

1593

1556

1462

1418

1371

1327

0.50 609 494 494 409 367 816 674 674 543 409 1003 837 837 704 526 1207 1070 1070 888 609 1379 1294 1294 1090 1070 1614 1517 1517 1298 1102 1888 1664 1664 1507 1278

0.60 572 461 461 361 319 780 634 634 509 361 959 772 772 660 476 1157 1013 1013 824 549 1332 1245 1245 1033 1013 1576 1477 1477 1259 1039 1842 1613 1613 1453 1228

– Shading – Airflow outside 450 cfm/ton.
NOTES:
1. Airflow based upon dry coil at 230v with factory-approved filter and electric heater (2 element heater sizes 019 through 037, 3 element heater sizes 043 through 061).
2. For FX4D models, airflow at 208 volts is approximately the same as 230 volts because the multi-tap ECM motor is a constant torque motor. The torque doesn’t drop off at the speeds the motor operates.

3. To avoid potential for condensate blowing out of drain pan prior to making drain trap: Return static pressure must be less than 0.40 in. wc. Horizontal applications of 043 – 061 sizes must have supply static greater than 0.20 in. wc.
4. Airflow above 400 cfm/ton on 049-061 size could result in condensate blowing off coil or splashing out of drain pan.

11

R-410A QUICK REFERENCE GUIDE
S R-410A refrigerant operates at 50-70 percent higher pressures than R-22. Be sure that servicing equipment and replacement components are designed to operate with R-410A refrigerant.
S R-410A refrigerant cylinders are rose colored. S Recovery cylinder service pressure rating must be 400 psig, DOT 4BA400 or DOT BW400. S R-410A refrigerant systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold
hose when charging into suction line with compressor operating S Manifold sets should be 700 psig high side and 180 psig low side with 550 psig low-side retard. S Use hoses with 700 psig service pressure rating. S Leak detectors should be designed to detect HFC refrigerant. S R-410A refrigerant, as with other HFCs, is only compatible with POE oils. S Vacuum pumps will not remove moisture from oil. S Do not use liquid-line filter driers with rated working pressures less than 600 psig. S Do not leave R-410A refrigerant suction line filter driers in line longer than 72 hours. S Do not install a suction-line filter drier in liquid line. S POE oils absorb moisture rapidly. Do not expose oil to atmosphere. S POE oils may cause damage to certain plastics and roofing materials. S Wrap all filter driers and service valves with wet cloth when brazing. S A factory approved liquid-line filter drier is required on every unit. S Do NOT use an R-22 TXV. S If indoor unit is equipped with a R-22 TXV or piston metering device, it must be changed to a hard-shutoff R-410A refrigerant
TXV. S Never open system to atmosphere while it is under a vacuum. S When system must be opened for service, recover refrigerant, evacuate then break vacuum with dry nitrogen and replace filter
driers. Evacuate to 500 microns prior to recharging. S Do not vent R-410A refrigerant into the atmosphere. S Do not use capillary tube coils. S Observe all warnings, cautions, and bold text.
TRAINING
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Edition Date: 6/19

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

12

Catalog No: IM-FB4C-FX4D-02
Replaces: IM-FB4C-FX4D-01