BOSCH 18 SEER2 Series Inverter Ducted Packaged Heat Pump Instruction Manual

: June 9, 2024
: Bosch

BOSCH 18 SEER2 Series Inverter Ducted Packaged Heat Pump

BOSCH 18 SEER2 Series Inverter Ducted Packaged Heat Pump-
PRODUCT

Product Information

The Inverter Ducted Packaged Heat Pump Bosch IDP Premium is a 3-ton capacity heat pump with 18 SEER2 series and uses R410A refrigerant. The product model number is BTC 761703103 A and the user manual version is 11.2022.

Safety Instructions

The user manual contains safety instructions and warnings that must be read and followed before proceeding with the installation or maintenance of the product. The warnings are identified by a warning triangle printed against a grey background. The following keywords are defined and can be used in this document:

DANGER indicates a hazardous situation which, if not avoided, will result in death or serious injury.
WARNING indicates a hazardous situation which, if not avoided, could result in death or serious injury.
CAUTION indicates a hazardous situation which, if not avoided, could result in minor to moderate injury.
NOTICE is used to address practices not related to personal injury.

The document also contains important information where there is no risk to people or property. High voltage warning is given in the manual, and it is advised to wait for three (3) minutes after disconnecting power prior to touching electrical components as they may hold a dangerous charge of 380 VDC, then verify DC Voltage is less than 42VDC at inverter TEST POINTS P-N.

Product Usage Instructions

The user manual contains detailed instructions on installation, airflow performance, indoor fan motor function, ductwork, condensate drain connection, air filter (not factory-installed), electrical wiring, start-up, system charge adjustment, system operation and troubleshooting, and maintenance. It is recommended to read and follow the instructions carefully to ensure proper usage of the product.

The manual also contains a wiring diagram and service information that should be kept with the unit and returned to the
service information pack upon completion of work.

Installation Instructions

Inverter Ducted Packaged Heat Pump Bosch IDP Premium
18 SEER2 Series | 3 Ton Capacity | R410A

BTC 761703103 A | 11.2022

Installation Instructions

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Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

Table of Contents

Key to Symbols and Safety Instructions

1.1 Key to Symbols 1.2 Safety
2 Component Location
3 Dimensions 3.1 Unit Dimensions 3.2 Dimensions – Back and Bottom 3.3 Dimensions – Left and Top
4 Installation 4.1 Pre-Installation 4.2 Rigging and Lifting 4.3 Location Restrictions 4.4 Rooftop Installation – Curb Mounting
5 Airflow Performance
6 Indoor Fan Motor Function
7 Ductwork
8 Condensate Drain Connection 8.1 Install Drain Pipe
9 Air Filter (Not Factory-Installed)
10 Electrical Wiring 10.1 Power Wiring 10.2 Grounding 10.3 Control Wiring
11 Start Up 11.1 System Start Up
12 System Charge Adjustment 12.1 Charging: Weigh-In Method 12.2 Subcooling Charging and Refrigerant Adjustment In Cooling
(Above 55°F Outdoor Temp.)

Installation Instructions

4 13 System Operation and Troubleshooting

22

4

13.1 Control Logic Description

22

4

13.2 Sensors (Thermistors/Pressure Transducer)

22

13.3 Defrost Description

23

6

13.4 Compressor Crankcase Heater Description

23

13.5 Reversing Valve Operation

23

7

13.6 Protection Functions

24

7

13.7 Fault Code Table

25

8

13.8 Parameter Point Check Table

26

9

13.9 Control Board Overview

27

10

13.10 Error Code Troubleshooting (ODU)

29

10

13.11 Error Code Troubleshooting (IDU)

35

10

13.12 Temperature and Resistance Relationship Tables (for Sensors)

36

10

13.13 Temperature and Resistance Relationship Tables (for T5)

37

12

13.14 Wiring Diagram

38

13 14 Maintenance

39

14.1 Cleaning Precautions

39

14

14.2 Regular Maintenance

39

15

16 16

16

17 17 17 17

19 19

20 20

20

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Installation Instructions

1 Key to Symbols and Safety Instructions 1.1 Key to Symbols
Warnings
Warnings in this document are identified by a warning triangle printed against a grey background. Keywords at the start of a warning indicate the type and seriousness of the ensuing risk if measures to prevent the risk are not taken.
The following keywords are defined and can be used in this document:
DANGER indicates a hazardous situation which, if not avoided, will result in death or serious injury.
WARNING indicates a hazardous situation which, if not avoided, could result in death or serious injury.
CAUTION indicates a hazardous situation which, if not avoided, could result in minor to moderate injury.
NOTICE is used to address practices not related to personal injury.
Important information
This symbol indicates important information where there is no risk to people or property.

1.2 Safety
Please read before proceeding
This document contains a wiring diagram and service information. This is customer property and is to remain with this unit. Please return to service information pack upon completion of work.
WARNING: HIGH VOLTAGE Failure to follow this warning could result in property
damage, severe personal injury, or death.
WAIT THREE (3) MINUTES after disconnecting power prior to touching electrical components as they may hold a dangerous charge of 380 VDC,then verify DC Voltage is less than 42VDC at inverter TEST POINTS P-N.
NOTICE: This document is customer property and is to remain with
this unit. Please return to service information pack upon completion of work. These instructions do not cover all variations in systems or provide for every possible contingency to be met in connection with the installation. Should further information be desired or should particular problems arise which are not covered sufficiently for the purchaser’s purposes, the matter should be referred to your installing dealer or local distributor.

WARNING:
This information is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience. Any attempt to repair a central air conditioning product may result in personal injury and/or property damage.

WARNING: ELECTRICAL SHOCK
Failure to follow this warning could result in property damage, severe personal injury, or death.
Disconnect all electric power, including remote disconnects before servicing. Follow proper lockout/tagout procedures to ensure the power cannot be inadvertently energized.

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WARNING: PERSONAL INJURY/ENVIRONMENTAL HAZARD Any attempt to repair a central air conditioning product may
result in property damage, severe personal injury, or death. These units use R-410A refrigerant which operates at 50 to 70% higher pressures than R-22. Use only R-410A approved service equipment. Refrigerant cylinders are painted a “Rose” color to indicate the type of refrigerant and may contain a “dip” tube to allow for charging of liquid refrigerant into the system. All R-410A systems with variable speed compressors use a POE oil (VG74 or equivalent ) that readily absorbs moisture from the atmosphere. To limit this `hygroscopic” action, the system should remain sealed whenever possible. If a system has been open to the atmosphere for more than 4 hours, the compressor oil must be replaced. Never break a vacuum with air and always change the driers when opening the system for component replacement.
CAUTION: HOT SURFACE Do not touch top of compressor. May cause minor to
severe burning. Failure to follow this Caution could result in property damage or personal injury.
CAUTION: HIGH PRESSURE Failure to follow proper procedures can result in personal
illness or injury or severe equipment damage. System contains oil and refrigerant under high pressure. Recover refrigerant to relieve pressure before opening system.
WARNING: GROUNDING REQUIRED Failure to inspect or use proper service tools may result
in equipment damage or personal injury. Reconnect all grounding devices. All parts of this product that are capable of conducting electrical current are grounded. If grounding wires, screws, straps, clips, nuts, or washers used to complete a path to ground are removed for service, they must be returned to their original position and properly fastened.
CAUTION: BURN HAZARD Failure to follow this warning will result in abrupt release
of system charge and may result in personal injury and/ or property damage. Extreme caution should be exercised when applying gauges to service ports.

Installation Instructions
WARNING: ELECTRICAL SHOCK Failure to follow this warning could result in property
damage, severe personal injury, or death. Grounding is essential before connecting electrical supply.
WARNING: This product can expose you to chemicals including Lead and Lead components, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
NOTICE: A manufactured (mobile) home installation must conform with the Manufactured Home Construction and Safety Standard, Title 24 CFR, Part 3280, or when this Standard is not applicable, the Standard for Manufactured Home Installations (Manufactured Home Sites, Communities and Set-Ups), ANSI/NCS A225.1, and/or MH Series Mobile Homes, CAN/CSA Z240.

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Installation Instructions
2 Component Location

Fusible Plug
HPS
T1 EEV Service Valves T5 Th Comp

Outdoor Fan
RV T3 T3L T2 PT Indoor Fan
T4

Figure 1

Component HPS PT T1 T2 T3 T4 T5

Descriptions High pressure switch Pressure transducer Return air temp. sensor Indoor coil temp. sensor Condenser temp. sensor Ambient temp. sensor Comp. discharge temp. sensor

Table 1 Component Descriptions

Component T3L Tf Th EEV RV COMP FP

Descriptions Condensor outlet temp. sensor
Radiator temp. sensor Comp. return temp. sensor Electronic expansion valve
Reversing valve Compressor Fusible Plug

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Dimensions

Unit Dimensions

Installation Instructions

Front
Condensate drain connection 3/4″ NPT (Trap required)

K1no-3c/k4o”uDtihaole HLciocgowohnnnvvno.o.l1lt7ta-a1/gg8/ee8″ D” Diaia

Figure 2

Heat Pump Model BRBA-36HWD1N1-M18 Table 2 Unit Dimensions

L 50-11/16″

Heat Pump Model BRBA-36HWD1N1-M18 Table 3 Unit Weights

Net Weight 400 lbs (182 kg)

W 35-1/16″
Gross Weight 420 lbs (191 kg)

H 46-13/16″

A 44-1/16″

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B 11-3/4″
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Installation Instructions 3.2 Dimensions – Back and Bottom

4-5/16″

OPTIONAL RETURN AIR
OPENING

21-9/16″

Bottom view
OPTIONAL SUPPLY AIR OPENING

7-7/8″ 2-9/16″

Back view

SUPPLY DUCT OPENING

RETURN DUCT OPENING

4-3/16″

Figure 3

Heat Pump Model BRBA-36HWD1N1-M18

C 47-13/16″

Table 4 Dimensions – Back and Bottom

8 |

21-9/16″

D 32-1/4″

E 9-15/16″

F 15-7/8″

G 15-3/4″

H 9-3/4″

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3.3 Dimensions – Left and Top Top view

Installation Instructions

Left side view

Figure 4

5-1/16″

6-5/8″

11-3/4″

6-5/8″

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Installation Instructions

4 Installation 4.1 Pre-Installation
Before installation, carefully check the following: 1. Unit should be installed in accordance with national and local safety codes, including but not limited to ANSI/NFPS No. 70, local plumbing and wastewater codes and any other applicable codes. 2. For rooftop installation, be sure the structure has enough strength to support the weight of unit. Unit must be installed on a field supplied roof curb or rack and leveled. 3. For ground level installation, a field supplied level slab must be used. 4. Condenser airflow should not be restricted. 5. On applications when a roof curb is used, the unit must be positioned on the curb so the front of the unit is tight against the curb. If the unit is to be mounted on a curb in a downflow application, refer to Figure 14, and convert panels prior to rigging and lifting. The panel removal process may require the unit to be on the ground.
4.2 Rigging and Lifting
ÙÔÏÚÕÐÛÐÑÖÐ×ÒØÓÒ
ÜÑÐØÿÔÕÐÖ×Ø

Exercise care when moving the unit. Do not remove any packaging until the unit is near the place of installation. Rig the unit by attaching chain or cable slings to the lifting holes provided in the base rails. Spreader bars, whose length exceeds the largest dimension across the unit, MUST be used across the top of the unit. When rigging/lifting the unit, the minimum height between the top of the rigging cables’ connection point and top of unit should be 36 inches. Refer to Figure 5.
CAUTION: Before lifting, make sure the unit weight is distributed
equally on the rigging cables so it will lift evenly.
CAUTION: All panels must be secured in place when the unit is lifted.
The condenser coils should be protected from rigging cable damage with plywood or other suitable material.
4.3 Location Restrictions
Ensure the top discharge area is unrestricted for at least 60 inches above the unit. Do not locate outdoor unit near bedrooms since normal operational noise levels may be disturbing to building occupants. Position unit to allow adequate space for unobstructed airflow, wiring, and serviceability. Do not restrict outdoor airflow. An air restriction at either the outdoor air inlet or the fan discharge may be detrimental to compressor life. 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 or other combustible materials. Slab-mounted units should be at least 2 inches (51 mm) above the highest expected water and runoff levels. Do not use unit if it has been under water. Maintain a distance of 24 inches between units. Position unit so water, snow, or ice from roof or overhang cannot fall directly on unit. See Figure 7 and Figure 8 for minimum clearance requirements.
Cold climate considerations (heat pump only)

Figure 5

NOTICE:
Precautions must be taken for units being installed in areas where snow accumulation and prolonged below-freezing temperatures occur.

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Units should be elevated 3-12 inches above the pad or rooftop, depending on local weather. This additional height will allow drainage of snow and will permit condensate water to drain when the unit is in defrost mode. Ensure that drain holes in unit base pan are unobstructed, preventing drainage of defrost water (See Figure 9).
If possible, avoid locations that are prone to snow drifts. If not possible, a snow drift barrier should be installed around the unit to prevent a build-up of snow on the sides of the unit.
Ensure that Condensate Drain side is pitched lower than the opposite side (see Figure 6).

Installation Instructions
Structure

Figure 8

Condensate drain side
Figure 6
Avoid Installs Near Bedrooms
Min 24″ Access Panel

Min. 60″ Unrestricted
Min 24″ Access Panel

Figure 7
A minimum clearance of 24″ should be maintained adjacent to all access/service panels. Refer to local code requirements for additional clearance requirements.

7
77

7

7
7 7

Min 24″
Snow barrier

7 7
7

7

77

7
7
7 7
7

7
7

7
7 7
7

7

77

7

77

7

77

Snow legs

7

3- 12″ Elevation

pad

Figure 9 Insulation Layer

Corrosive Environment
Exposure to a corrosive environment may shorten the life of the equipment, corrode metal parts, and/or negatively affect unit performance. Corrosive elements include, but are not limited to: sodium chloride, sodium hydroxide, sodium sulfate, and other compounds commonly found in ocean water, sulfur, chlorine, fluorine, fertilizers, and various chemical contaminants from industry/manufacturing plants. If installed in areas which may be exposed to corrosive environments, special attention should be given to the equipment placement and maintenance.
Lawn sprinklers/hoses/waste water should not spray directly on the unit cabinet for prolonged periods of time.
In coastal areas: locate the unit on the side of the building or roof away from the waterfront.
Fencing or shrubbery may provide some shielding protection to the unit, however minimum unit clearances must still be maintained.
Every three months, wash the outdoor coil and any exposed cabinet surfaces.

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Installation Instructions

4.4 Rooftop Installation – Curb Mounting
The manufacturer does not supply roof curbs, they must be field supplied. Refer to Figure 11 for recommended roof curb dimensions. On applications when a roof curb is used, the unit must be positioned on the curb so the front of the unit is tight against the curb. The default orientation from the factory is for horizontal airflow. Convert the unit to downflow using the following procedure:
1. Remove sheet metal screws from both the supply air and return air panels. Refer to Figure 14.
2. Add foam tape on the perimeter of the non painted side of each panel. 3. Move and re-secure the panels to the downflow location using the sheet
metal screws from step 1. For more information, refer to the the Conversion Kit Manual included with each heat pump unit. Install the field-supplied roof mounting curb according to the Installation Instructions supplied with the curb. Install insulation, cant strips, roofing, and flashing. Ductwork must be attached to curb.
NOTICE: The gasketing of the unit to the roof curb is critical for a water tight seal. Install gasketing material supplied with the field supplied roof curb. Improperly applied gasketing also can result in air leaks and poor unit performance.
CAUTION: The unit must be secured to the curb by installing screws
through the bottom of the curb flange and into the unit base rails.

1″ 2″

14-1/4″ 4-1/4″

Insulation layer

12-5/8″ 30-5/8″

1″ 14″

14″

46-1/16″

2″
Figure 11 Roof Curb Dimensions
For units applied with a roof curb, the minimum clearance may be reduced from 1 inch to 1/2 inch between combustible roof curb material and supply air duct.

NOTICE: UNIT/STRUCTURAL DAMAGE HAZARD
Failure to follow this caution may result in property damage. Ensure there is sufficient clearance for saw blade when cutting the outer horizontal flange of the roof curb so there is no damage to the roof or flashing.

A A

A
INSULATION LAYER

B
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. Attach ductwork to curb (flanges of duct rest on curb) 4. Recommended insulated panels: 1 in. (25.4 mm) thick fiberglass 1 lb. density

C
SUPPLY AIR
1″

Figure 10 Roof Curb Details

CURB

B 14-1/4″

Table 5 Roof Curb Details – inches

C

D

14″

46-1/16″

A
43-1/2″
D

C
RETURN AIR
E 16″

1″ 12-5/8″
E F

F 30-5/8″

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Installation Instructions

Airflow Performance

Airflow performance data is based on cooling performance with a coil and no filter in place. Check the performance table (Table 6) for appropriate unit size selection.
External static pressure should stay within the minimum and maximum limits shown in the table below in order to ensure proper operation of both cooling, heating, and electric heating operation.

Model Number
BRBA-36HWD1N1-M18

Motor Speed *

Tap (1) Tap (2) Tap (3) Tap (4) Tap (5)

SCFM Watts Amps SCFM Watts Amps SCFM Watts Amps SCFM Watts Amps
SCFM
Watts Amps

0[0] 925 114 1.07 1103 162 1.45 1132 193 2.03 1355 296 2.52
1522
426 3.49

0.1[.02] 807 120 1.12 993 169 1.51 1084 201 2.08 1310 301 2.56
1465
432 3.54

SCFM

External Static Pressure-Inches W.C.[kPa]

0.2[. 05] 0.3[.07] 0.4[.10] 0.5[.12] 0.6[.15]

723

658

/

126

130

/

1.17

1.19

/

911

841

776

710

596

175

181

187

193

197

1.56

1.6

1.65

1.69

1.72

1027

972

907

832

762

207

214

221

229

238

2.15

2.17

2.20

2.27

2.31

1270

1180

1049

989

931

307

312

318

323

327

2.6

2.64

2.68

2.71

2.74

1364

1291

1231

1177

1121

438

443

448

452

456

3.58

3.62

3.65

3.68

3.7

0.7[.17] / / / / / / 700 243 2.39 870 331 2.77
1066
460 3.74

0.8[.20] / / / / / / 637 247 2.42 813 336 2.81
1017
466 3.78

Table 6

Bold outlined areas represent airflow outside of the required 300-450 cfm/ton range.

NOTES:
1. This table is only used to select the highest blower speed.
2. The rated airflow of systems without electric heater kits requires between 300 and 450 cubic feet of air per minute (CFM).The rated airflow of systems with electric heater kits requires between 350 and 450 cubic feet of air per minute (CFM).
3. The air distribution system has the greatest effect on airflow. Therefore, the contractor should use only industry-recognized procedures.
4. Duct design and construction should be carefully done. System performance can be lowered dramatically through poor design or workmanship.
5. Air supplier ducts should be located along the perimeter of the conditioned space and properly sized. Improper location or insufficient air flow may cause drafts or noise in the ductwork.
6. Installers should balance the air distribution system to ensure proper quiet airflow to all rooms in the home. An air velocity meter or airflow hood can be used to balance and verify branch and system airflow (CFM).
7. 4 Speed Fan default is Tap (1), Tap (2), Tap (3), Tap (4)

For instructions on how to select fan speeds, refer to Section 6 of this manual.

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Installation Instructions

Indoor Fan Motor Function

System Operation and Function This unit can run with either 4 Stage Fan Control or 2 Stage Fan Control. The factory default is 4 Stage Fan Control. To change the factory default parameters, refer to the information provided below.
Four Stage Fan Control The IDP 3 Ton supports up to 4 fan speeds. The fan speed will automatically change according to the temperature difference between T1 (return air temperature) and Ts (estimated thermostat set point). Higher differences in temperature between T1 and Ts relate to higher fan speeds. This fan control is supported by either a single or two stage thermostat.
The ECM Constant Torque motor has 5 selectable speed taps. The unit can use up to 4 fan speeds by setting the SW6-4 dip switch to the “ON” position (default). For determining the required airflow, refer to the Airflow Performance Table (Table 6). To select the fan speeds, change SW6-1 and SW6-2 dip switches, refer to Table 7 for dip switch speed configuration.

Figure 12

Mid-

SW6-4 SW6-1 SW6-2

High

Mid

Low

high

OFF

2

1

OFF

ON

3

2

1

ON*

OFF*

4

3

2

1

ON

5

4

3

2

Table 7 *Note: Default Fan Speed is SW6-4 ON, SW6-1 ON, SW6-2 OFF

Two Stage Fan Control The IDP supports two stage fan control which requires a two stage thermostat (Y1&Y2). When there is a call for Y2, the blower motor will turn to high speed setting. When there is a call for Y1, the blower motor will turn to low speed setting. Unit will run at low speed setting when there is only G call. It will run in high speed setting when there is W/W1/W2 signal (when the electric heat kit is on).

Customers can select two stage fan control by setting the SW6-4 dip switch to the “OFF” position. Select the two fan speeds using the SW6-1 and SW6-2 dip switches, refer to Table 8. Refer to Airflow Performance Table (Table 6) for reference airflow.

If 2 stage thermostat is not available, single stage thermostat may be used, please refer to Wiring Diagram section for wiring instructions. If Y1 and Y2 are jumped, the unit will only run in high stage fan speed.

Mid-

SW6-4 SW6-1 SW6-2

High

Mid

Low

high

OFF

2

/

1

/

OFF

ON

3

/

1

/

OFF

ON

OFF

4

/

2

/

ON

5

/

3

/

Table 8

Anti-Cold Air Fan Delay The Anti-Cold Air Fan Delay function utilizes a sensor (T2) located on the indoor coil, which prevents the blower from turning on until the coil has reached a certain temperature. This feature prevents cold air blow during heating operation and is activated by setting SW6-3 dip switch to the “ON” position (default), refer to Figure 12 and Table 9.
1. When SW6-3 dip switch is set to the “ON” position and the unit is in heating mode, the Anti-Cold Air Fan Delay function will activate based on the following entry conditions (all 3 conditions must be met):
a. Indoor Coil Temperature (T2) < 82.4 °F b. Electric heat kit is turned off c. There is a call for Y1 from thermostat to indoor unit
2. This function will deactivate if ONE OF the following exit conditions are met OR the system has been operating in heating mode for 15 minutes.
a. T2 89.6 °F b. Heater kit is turned on c. The system is NOT running Heat mode
3. During the heating mode, if one of the exit conditions of Anti-Cold Air is satisfied, the blower motor will turn on in first stage fan speed.
4. During the heating mode, if all of the entry conditions of Anti-Cold Air are met and maintained for 120s, the blower motor will change to first stage speed.

SW6-3
ON OFF
Table 9 Note: Default is ON

Heat: Anti-Cold Air Fan Delay via Temp Sensor Heat: Timed Fan Delay

Heating Fan Delay If SW6-3 dip switch is set to the “OFF” position (refer to Table 9), and the unit is in heating mode, the blower will operate with a 90 second delay with the fan speed dictated by Y1 or Y2 signal.

Passive Dehumidification (Optional) IDP 3 Ton has a Passive Dehumidification function which lowers the fan speed and optimizes the compressor operation with a DH call from the thermostat. This function requires proper DH wiring from the indoor unit to the thermostat (with a humidistat).

If DH wire is not connected, the unit will still function normally, but will not be able to run in dehumidification mode.

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Installation Instructions

7 Ductwork
Field ductwork must comply with the National Fire Protection Association NFPA 90A, NFPA 90B and any applicable local ordinance(s).
WARNING: FIRE HAZARD AND CARBON MONOXIDE Do not, under any circumstances, connect return ductwork
to any other heat producing device such as fireplace insert, stove, etc. Unauthorized use of such devices may result in fire, carbon monoxide poisoning, explosion, personal injury or property. damage.

Return Air Supply Air Roof Flashing
Angle Iron Frame

Sheet metal ductwork run in unconditioned spaces must be insulated and covered with a vapor barrier. Fibrous ductwork may be used if constructed and installed in accordance with SMACNA Construction Standard on Fibrous Glass Ducts. Ductwork must comply with National Fire Protection Association as tested by U/L Standard 181 for Class I Air Ducts. Check local codes for requirements on ductwork and insulation.
Duct system must be designed within the range of external static pressure the unit is designed to operate against. It is important that the system airflow be adequate. Make sure supply and return ductwork, grills, special filters, accessories, etc. are accounted for in total resistance. See airflow performance tables in Section 5 of this manual.
Design the duct system in accordance with “ACCA” Manual “D” Design for Residential Winter and Summer Air Conditioning and Equipment Selection. Latest editions are available from: “ACCA” Air Conditioning Contractors of America, 1513 16th Street, N.W., Washington, D.C. 20036. If duct system incorporates flexible air duct, be sure pressure drop information (straight length plus all turns) shown in “ACCA” Manual “D” is accounted for in system.
If an elbow is included in the plenum close to the unit, it must not be smaller than the dimensions of the supply duct flange on the unit.
NOTICE:
The front flange on the return duct (if connected to the blower casing) must not be screwed into the area where the power wiring is located. Drills or sharp screw points can damage insulation on wires located inside unit.

Figure 13 Rooftop Installation – Frame Mounting

SUPPLY AIR PANEL

SHEET METAL SCREWS

RETURN AIR PANEL

Figure 14 Note: Refer to downflow conversion instructions provided with the unit

Return Air Roof Flashing

Supply Air

Secure all ducts to roof curb and building structure on downflow 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 using proper fasteners for the type of duct used and tape the duct-to unit joint as required to prevent air leaks.

Roof Flashing
Angle Iron Frame

NOTICE:
When fastening ductwork to the side duct flanges on the unit, insert the screws through the duct flanges only. DO NOT insert the screws through the casing. Outdoor ductwork must be insulated and waterproofed.

Figure 15 Typical Rooftop Downflow Application with Frame

Be sure to note supply and return openings. Refer to Figure 3 for information concerning supply and return air duct dimensions.

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Installation Instructions

Unit should be installed in accordance with national and local safety codes, including but not limited to ANSI/NFPS No. 70, local plumbing and wastewater codes and any other applicable codes.
8.1 Install Drain Pipe
1. Ensure drain lines do not block access to front of the unit. Minimum clearance of 24 inches is required for filter, coil or blower removal and service access.
2. Make sure unit is leveled or pitched slightly towards primary drain connection so that water will drain completely from the pan.
3. Do not reduce drain line size to less than connection size provided on condensate drain pan.
4. All drain lines must be pitched downward away from the unit at a minimum of 1/8″ per foot of line to ensure proper drainage.
5. Do not connect condensate drain line to a closed or open sewer pipe. Run condensate to an open drain or run line to a safe outdoor area.
6. The drain line should be insulated where necessary to prevent sweating and damage due to condensate forming on the outside surface of the line.
7. Make provisions for disconnecting and cleaning of the primary drain line should it become necessary. Install a 2 inch trap in the primary drain line as close to the unit as possible. Make sure that the top of the trap is below connection to the drain pan to allow complete drainage of pan.

1in.(25mm)min

TRAP OUTLET

2in.(51mm)min

Air Filter (Not Factory-Installed)

Filters and filter racks are not included with the unit and must be field supplied.
An external filter or other means of filtration must be properly sized for a maximum of 300 feet/min. air velocity or what is recommended for the type of filter installed.
Filter application and placement are critical to airflow, which may affect the heating and cooling system performance. Reduced airflow can shorten the life of the system’s major components, such as motor, elements, heat relays, evaporator coil or compressor. Consequently, we recommend that the return air duct system have only one filter location. For systems without a return air filter grill, multiple filter grills can be installed at each of the return air openings.
If adding high efficiency filters or electronic air filtration systems, it is very important that the air flow is not reduced. If air flow is reduced the overall performance and efficiency of the unit will be reduced. It is strongly recommended that a professional installation technician is contacted to ensure such filtration systems are installed correctly.
Do not double filter the return air duct system. Do not filter the supply air duct system. This will change the performance of the unit and reduce airflow.
WARNING: FIRE HAZARD Do not operate the system without filters. A portion of the
dust suspended in the air may temporarily lodge in the duct runs and at the supply registers. Any circulated dust particles could be heated and charred by contact with the air handler elements. This residue could soil ceilings, walls, drapes, carpets and other articles in the house. Soot damage may occur with filters in place, when certain types of candles, oil lamps or standing pilots are burned.

Figure 16

Heat Pump Model

No.

BRBA-36HWD1N1-M18

1

Table 10

Size Recommended 16″x10″x1″

When making drain fitting connections to the drain pan, use a thin layer of Teflon paste, silicone or Teflon tape and install by hand tightening.

When making drain fitting connections to drain pan, do not overtighten. Over- tightening fittings can split pipe connections on the drain pan.

16 |

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Installation Instructions

Electrical Wiring

Field wiring must comply with the National Electric Code (NEC) and any applicable local ordinance.
WARNING: ELECTRICAL SHOCK Disconnect all power to unit before installing or servicing.
More than one disconnect switch may be required to de-energize the equipment. Hazardous voltage can cause severe personal injury or death.
10.1 Power Wiring
1. It is important that proper electrical power is available for connection to the unit being installed. See the unit nameplate, wiring diagram, and electrical data in the installation instructions for more detailed requirements. Voltage tolerance should not be over 10% from rating voltage.
2. If any of the wiring must be replaced, replacement wiring must be the same type as shown in nameplate, wiring diagram and electrical data sheet.
3. Install a branch circuit disconnect of adequate size to handle starting current, located within sight, and readily accessible to the unit.
4. Electric Heater: If the optional Electric Heat Kit is installed, the unit should be equipped with suitable circuit breakers or fuse. Refer to Table 11 and 12 for more information. These breaker(s) protect the internal wiring in the event of a short circuit and serve as a disconnect. Circuit breakers installed within the unit do not provide over-current protection of the supply wiring and therefore may be sized larger than the branch circuit protection. Supply circuit power wiring must be 221 °F minimum copper conductors only. Refer to Table 11 and 12 for ampacity, wire size and circuit protector requirements. Supply circuit protective devices may be either fuses or “HACR” type circuit breakers.1-3/8″ knockouts inside the cabinet are provided for connection of power wiring to electric heater. Power wiring is connected to the power terminal block in unit electric cabinet. See Electric Heater Kit Installation Instructions for details.
5. See wiring diagram located on inside of control board access panel for proper wiring instructions.
10.2 Grounding
WARNING: ELECTRICAL SHOCK The unit must be permanently grounded. Failure to do so
can result in electrical shock causing personal injury or death.
The unit must be electrically grounded in accordance with local codes and the National Electric Code (NEC).
Grounding may be accomplished by attaching ground wire(s) to ground lug(s) provided in the unit wiring compartment.

10.3 Control Wiring
WARNING: FIRE HAZARD Low voltage control wiring should not be run in conduit
with high voltage wiring. Keep distance between the two conduits per local codes.
18 AWG. color-coded low voltage wire should be used for lengths less than 100 ft. For wire lengths longer than 100 ft., 16 AWG. wire should be used.
7/8″ knockout hole should be used to route control wires into the unit. After installation, ensure separation of low voltage and high voltage
wiring is maintained.
Refer to Figure 18 for thermostat wiring diagrams.

Indoor Control Board
C R Y1 Y2 G B/O DH W2 W1
L1 L2

High voltage power supply
Figure 17

Control wiring

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Installation Instructions

Support 3H and 2C thermostat

R C Y Y2 G O/B W/E
H/DH THERMOSTAT

RED

R

BROWN

C

YELLOW

Y1

PURPLE

Y2

GREEN

G

BLUE B

WHITE

W1

W2

GRAY

Dh

UNIT CONTROL BOARD TERMINAL STRIP

Support 3H and 1C thermostat

RED

R

BROWN

C

Y

YELLOW

Y1

Y2

G

GREEN

G

BLUE

O/B

B

W/E

WHITE

W1

WHITE/BLACK

W2

GRAY

H/DH

Dh

THERMOSTAT

UNIT CONTROL BOARD TERMINAL STRIP

Support 1H and 1C thermostat

R C Y
G O/B
H/DH THERMOSTAT

RED

R

BROWN

C

YELLOW

Y1

Y2

GREEN

G

BLUE

B

W1

W2

GRAY

Dh

UNIT CONTROL BOARD TERMINAL STRIP

Figure 18 Thermostat Wiring Diagrams

Dh wiring is optional and requires a thermostat with a humidistat. Dh functions as Passive Dehumidication and will downstage the indoor fan speed. System will operate according to normal sequence of operations if Dh wiring is absent.

Y2 wiring is optional for 4 speed fan control. For 2 stage fan control Y2 wiring is required.

Support 4H and 2C thermostat

R C Y Y2 G O/B W/E W2 H/DH THERMOSTAT

RED

R

BROWN

C

YELLOW

Y1

PURPLE

Y2

GREEN

G

BLUE B

WHITE

W1

WHITE/BLACK W2

GRAY

Dh

UNIT CONTROL BOARD TERMINAL STRIP

Support 2H and 2C thermostat

R C Y Y2 G O/B
H/DH THERMOSTAT

RED

R

BROWN

C

YELLOW

Y1

PURPLE

Y2

GREEN

G

BLUE

B

W1

GRAY

W2
Dh
UNIT CONTROL BOARD TERMINAL STRIP

Support 2H and 1C thermostat

R C Y
G O/B W/E
H/DH THERMOSTAT

RED

R

BROWN

C

YELLOW

Y1

Y2

GREEN

G

BLUE

B

WHITE

W1

W2

GRAY

Dh

UNIT CONTROL BOARD TERMINAL STRIP

Dashed lines in the above thermostat wiring diagrams refer to optional wiring (wiring for Passive Dehumidification Function and/ OR Electric Heat, and 2 stage fan control). For thermostat wiring please refer to the Owner’s Manual of the thermostat.

B wire must be used with heat pump system only, the valve energizes in heating.

reversing

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WARNING: ELECTRICAL SHOCK
Label all wiring prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. Verify proper operation after servicing.

Installation Instructions

Start Up

System Start Up
1. Ensure Sections 4, 5, 6, 7, and 8 have been completed. 2. Set System Thermostat to OFF.

Size (Tons)

Voltage – Phase Frequency

Compressors (each)
RLA LRA

36 (3)

208/2301-60

19A

52A

OD Fan Motors (each)
FLA
2.1A

Supply Blower Motor
FLA
3.8A

Unit Circuit

MCA¹ (Amps)

Max Fuse²/ Breaker³ Size
(Amps)

28.7

45

Table 11 Electrical Data Without Electric Heat

Heater Circuit Dual Point

Single Point

Model

kW 208/ 240

Stages

FLA (Amps)

Max Fuse²/

MCA¹ Breaker³ MCA Breaker³

(Amps) Size (AMPS) Size

(Amps)*

(Amps)**

EHK-05J 3.8/5 1 18.1/20.8 23/26 EHK-08J 5.6/7.5 1 27.1/31.3 34/40 EHK-10J 7.5/10.0 1 36.1/41.7 46/53

25/30 35/40 50/60

52/55 63/68 74/81

60/60 70/70 80/90

EHK-15J 11.3/15 2 54.2/62.5 68/79 70/80 97/107 100/110

Table 12 Electrical Data With Electric Heat
1. Minimum Circuit Ampacity. 2. Maximum Over Current Protection per Standard UL 1995. 3. Fuse or HACR circuit breaker size field installed.

Max Fuse/Breaker Sizes are for electric heater ONLY (dual point electric heat). DOES NOT include breaker size for the unit. **Max Fuse/Breaker Sizes include breaker size for the unit AND electric heat (single point electric heat).

Figure 19 3. Turn on disconnect to apply power to the indoor and outdoor units.
ON O FF
Figure 20 4. Wait one (1) hour before starting the unit if compressor crankcase heater is used and the outdoor ambient temperature is below 70 °F.
60 MIN.

Refer to Electric Heat Kit Installation Manual, some heater kits include fuses from the manufacturer.
WARNING: ELECTRICAL SHOCK / FIRE HAZARD Any power supply and circuits must be wired and
protected in accordance with federal, state and local electrical codes.

Figure 21 5. Set system thermostat to ON.

Figure 22

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Installation Instructions

System Charge Adjustment

The unit comes precharged from the factory with 7-8 lb-oz of refrigerant. Follow Section 12 for charge adjustments i.e if components have been replaced, or if there is a suspected leak.

80 ºF 70ºF

12.1 Charging: Weigh-In Method
Weigh-in method is recommended anytime a system charge is being replaced. Weigh-in method can also be used when power is not available to the equipment site or operating conditions (indoor/outdoor temperatures) are not in range to verify with the subcooling charging method.

Heat Pump Model BRBA-36HWD1N1-M18 Table 13

Refrigerant Charge (lb-oz) 8-6

Indoor Temp
Figure 24
2. Stabilize the system.
3. After starting the system in cooling mode, short press “FORCE” button, and a “|– ” symbol should appear. System may take 10 minutes to ramp up. Operate the system for a minimum of twenty (20) minutes.

12.2 Subcooling Charging and Refrigerant Adjustment In Cooling (Above 55°F Outdoor Temp.)
1. Check the outdoor ambient temperatures.
Subcooling (in cooling mode) is the only recommended method of charging above 55°F outdoor ambient temperatures. For outdoor ambient temperatures below 55°F, use weigh-in charge method.

It is important to return in the spring or summer to accurately charge the system in the cooling mode when outdoor ambient temperature is above 55°F.

Outdoor Temperature Above 55ºF
120ºF
55ºF

Outdoor Temperature Below 55ºF
55ºF

Figure 25
SW1 is not used.
After a twenty (20) minute stabilization period operating at 100% capacity (72 Hertz ), maintain continuous operation while adjusting refrigerant charge. After adjusting, operate system for a minimum of five (5) minutes for system to stabilize, otherwise repeat step 3.

Outdoor Temp1

Outdoor Temp2

Figure 23 For best results the indoor temperature should be kept between 70°F to 80°F.

20 MIN.
Figure 26 4. Calculate subcooling value on liquid line (According to Table 14) Measured Liquid Line Temp. = ____ºF Measured Liquid Line Pressure = ___ PSIG Calculate subcooling value = ____ºF

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Figure 27 Ensure the temperature sampling position as shown above.

Installation Instructions
Connect gauges to refrigerant bottle and unit as illustrated (Figure 27 and 28).
Purge all hoses. Open tank. Stop adding refrigerant when subcooling matches the charging chart
(Table 14) Final Subcooling value.
Recover refrigerant if the subcooling reading from Table 14 is higher than the designed value (Table 15).

If calculated subcooling value is lower than the design subcooling value (Table 15), please add refrigerant. Repeat steps 2 through 4.

Liquid

Final Subcooling(°F)

Line Temp 6

7

8

9

10

11 12

13

(°F)

Liquid Gauge Pressure (PSI)

55 173 176 179 182 185 188 191 195

60 188 191 195 198 201 204 208 211

65 204 208 211 215 218 221 225 229

70 221 225 229 232 236 239 243 247

75 239 243 247 251 255 259 262 266

80 259 262 266 270 275 279 283 287

85 279 283 287 291 295 300 304 309

90 300 304 309 313 318 322 327 331

95 322 327 331 336 341 346 351 355

100 346 351 355 360 365 370 376 381

105 370 376 381 386 391 397 402 407

110 397 402 407 413 418 424 430 435

115 424 430 435 441 447 453 459 465

120 453 459 465 471 477 483 489 496

125 483 489 469 502 508 515 521 528

Table 14 R-410A Refrigerant Chart – Final Subcooling

Heat Pump Model BRB-36HWD1N1-M18 Table 15

Design Subcooling 12°F ± 4°F

5. Adjust refrigerant level to attain proper gauge pressure.

Add refrigerant if the subcooling reading from Table 14 is lower than the designed value (Table 15).

Figure 28 6. Stabilize the system. Wait 5 minutes for the system condition to stabilize between adjustments.
When the subcooling matches the chart, the system is properly charged.
Remove gauges. Replace service port caps to prevent leaks. Tighten finger tight plus
an additional 1/6 turn. 7. Record System Information for reference (Table16). Record system
pressures and temperatures after charging is complete.
The subcooling also can be calculated by pressing check button after getting T3 and T3L temperatures (refer to table 21).

Description Outdoor model number Measured Outdoor Ambient Measured Indoor Ambient Check Condenser Outlet Temp.(T3L) Check Condenser Temp.(T3) Calculate subcooling value =T3-T3L
Table 16

Value
°F °F °F °F °F

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| 21

Installation Instructions

System Operation and Troubleshooting

13.2 Sensors (Thermistors/Pressure Transducer)

13.1 Control Logic Description

T1 = Return Air Temperature

The variable speed system adopts the same 24VAC control as any conventional heat pump.
The compressor’s speed is controlled based on coil pressures monitored by the unit’s pressure transducer. To ensure stable and adequate capacity, the compressor speed will modulate relative to evaporator pressure during cooling operation and relative to condensing pressure during heating operation. The target pressure can automatically adjust based on compressor operation so optimal capacity can be achieved. Target pressure can be manually adjusted (SW4) to achieve improved dehumidification and capacity demands.

— Indoor Fan Control T2 = Indoor Coil Temperature
— Anti-cold air function in heating mode T3 = Outdoor Coil Temperature High/Low temperature protection
— Outdoor fan control (cooling mode) — Defrost control (heating mode)

ON OFF 1 2 3 4
Figure 29

Switch ON
SW4-1 OFF ON
SW4-2 OFF ON
SW4-3 OFF ON
SW4-4 OFF
Table 17 *Factory Default

Description Must be set at “ON” position
Unused Unused Must be set to “OFF” position Adaptive capacity output disabled Adaptive capacity output enabled Accelerated cooling/heating Normally cooling/heating

Adaptive capacity function is a “self-learning function” which allows a range of target coil temperatures to adapt for better unit operation and reduced short cycling.
Accelerated cooling/heating function changes the initial target coil temperature to provide “enhanced comfort” by increasing unit capacity.

T4 = Ambient Temperature — Operating condition permission — Defrosting condition permission — Outdoor fan control (heating mode)
T5 = Compressor Discharge Temperature — High/Low temperature protection — Electronic Expansion Valve (EEV) (ODU/heating mode only)
Th = Compressor Return Temperature T3L = Liquid Line Temperature TF = Control Board Module Temperature
— Inverter High Temperature Protection
Pressure transducer — Compressor frequency control — Electronic Expansion Valve (EEV) control (in both heating and cooling modes) — High pressure protection (heating mode) — Low pressure protection (cooling mode)

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Installation Instructions

13.3 Defrost Description
The Demand Defrost Control (DDC) monitors the ODU coil temperature using thermistor (T3). A second thermistor (T4) monitors outdoor ambient temperature. Based on these parameters, as well as accumulative run time and high pressure, the DDC calculates proper initiation of defrost.
Any one of the below three conditions is required to enter defrost:
1. The calculated temperature difference between the outdoor temperature (T4) and the coil temperature (T3) is called Delta T. After Delta T is achieved and continues for 3 minutes. — T4 39°F, Delta T = 18°F
— T4 30°F, Delta T = 16°F
— T4 19°F, Delta T = 14°F
— When T4 < 19°F, T3 < 9°F, accumulative compressor run time 80 minutes.
2. After “Minimum Run Time” (MRT) is achieved. MRT is based on outdoor ambient temperature (T4), for example: — MRT is 4 hours when: T4 < 23°F
— MRT is 2 hours when: 23°F T4 < 42°F 3. After the high pressure saturation temperature drops below 82°F
for 20 minutes.
Defrost will terminate once outdoor coil temperature (T3) reaches 64°F for a period of 1 minute or defrost time has exceeded 8 minutes.
Defrost Termination Settings (SW5) offers different defrost termination options for enhanced defrost for different geographical and outdoor conditions.
SW5
ON OFF 1 2

Figure 30

Defrosting Choice
ON
OFF Remarks Table 18

SW5-1

SW5-2

Remarks

Operating time is Defrosting extended for

reduced by 10%

60 seconds

Normal Enter defrost

Normal Quit defrost

Default

Manual Defrost: 1. System must have a call for heat and have been operating for a minimum of 8 minutes. 2. Press “Force” button on inverter board for 6 seconds to begin forced defrost. 3. Wait approximately 40 seconds for defrost to initiate. 4. Once defrost initiates, the display will indicate “dF”. 5. Defrost test will terminate automatically, after which the display will indicate running speed. 6. If a second defrost test is required, repeat steps 2-5 after 5 minutes.
13.4 Compressor Crankcase Heater Description
Refrigerant migration during the OFF cycle can result in noisy start-ups, therefore a CrankCase Heater (CCH) is used to minimize refrigerant migration thereby minimizing start-up noise and/or bearing “wash out”. All CCHs must be installed on the lower half of the compressor shell. Its purpose is to warm the compressor during the OFF cycle, driving refrigerant from compressor. After extended shutdown periods in cold weather, it is recommended to allow CCH to be energized for at least 12 hours prior to compressor operation by applying line voltage to heat pump with thermostat OFF.
CCH operation energizes: 1. First time line voltage is applied and compressor discharge temperature T5 < 53.6°F. 2. Compressor stops running for 3 hours (outdoor ambient temperature T4 < 41°F OR compressor discharge temperature T5 < 53.6°F).
CCH operation de-energizes: 1. Compressor discharge temperature T5 60.8°F. 2. Compressor start running.
13.5 Reversing Valve Operation
Reversing valve energizes during heat mode and de-energizes in cool mode.
During a heat call on first time operation the unit will run about 1 minute in cooling to build up pressure for reversing valve to change.

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Installation Instructions
13.6 Protection Functions
Outdoor coil temperature protection (T3) i. If T3 > 143.6°F, compressor is de- energized. ii. If T3 < 129.2°F, compressor is energized.
Ambient temperature protection (T4) i. If 23°F T4 < 125°F, unit can operate in cooling. ii. If 4°F T4 < 86°F, unit can operate in heating. iii. If T4 < 4°F, heat pump will provide 24V control to indoor unit energizing electric heat (if installed).
See Product Specification for extended performance data.
Discharge Temperature (DT) protection (T5) i. If DT > 230°F during cooling mode, the compressor will stop. ii. If DT < 212°F during cooling mode, the compressor will restart. iii. If DT > 230°F during heating mode, the compressor will stop. iv. If DT < 212°F during heating mode, the compressor will restart.
High Pressure (HP) protection (mechanical open/close pressure switch) i. High Pressure Switch opens at P > 580 PSIG, the compressor and outdoor fan stop. ii. High Pressure Switch closes at P < 435 PSIG, the compressor and outdoor fan restart.
Low Pressure (LP) protection i. If Low Pressure < 43.5 PSI for 5 minutes during cooling mode, the compressor and outdoor fan will stop.The system will attempt to run again after 6 minutes. ii. If condensing temp. Tc < outdoor ambient temp. T4 during heating mode, the compressor and outdoor fan will stop.
Module (inverter) protection (TF) i. If TF > 172°F, the compressor and outdoor fan will stop. ii. If TF < 160°F, the compressor and outdoor fan will restart.

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13.7 Fault Code Table

Outdoor Control Board Code Fault Description (Sensor)

C3

The coil sensor is seated fault in cooling (T3)

E4

Temperature sensor fault (T3, T4, T5, Th, T3L)

E5

High/low voltage protection

E6

DC fan motor fault

E7

Compressor discharge sensor is seated fault (T5)

E9

EEPROM

H0

Communication fault in main control chip

H5*

5 times (P2) protection in 100 minutes, system lockup

H8

Pressure transducer fault (PT)

P0

High module radiator temperature protection (TF)

P1

High pressure switch protection (HPS)

P2

Low pressure protection in cooling or heating (PT)

P3

Compressor over current protection

P4

High compressor discharge temperature protection (T5)

P5

Condensor coil temperature protection in cooling (T3)

P8

DC fan motor typhoon protection

PH

Low discharge superheat protection

F1

High pressure switch (HPS) fault

L0-L9

IPM module protection

System Protection Status Codes** Forced operation mode

L

Running indication under T3 limited condition

D

Running indication under T5 limited condition

P

Running indication under compressor ratio limited condition

F

Running indication under TF limited condition

C

Running indication under current limited condition

U

Running indication under low voltage limited condition

A

Running indication under return oil model

dF

Running indication under defrost model

Table 19 * Fault requires hard restart

** If the first digit shown on the control board LED is one of the following protection codes (followed by two numerical digits which show the current compressor frequency in Hz), the unit will continue to run but in a limited condition. The only exception is when the system is in defrost mode, which only displays “dF” (without any numerical digits following).

Indoor Unit Board LED Codes Number of flashes Always ON 1 2 3 4 5 6
Table 20

Description Normal Dehumidification mode active Reserved Anti-cold air function active Temperature sensor fault (T1) Temperature sensor fault (T2) Communication error

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Installation Instructions | 25

Installation Instructions
13.8 Parameter Point Check Table
To display system parameters, press the “Check” button to index through the series of parameters available. The first time you press the “Check” button, it will display the sequence, and after 1 second it will display the value of the parameter. If you press the “Check” button again, it will display the next sequence. Refer to Figure 32 for check button location on the control board.
Check button

Normal Status, last two digits will display under the following conditions i. Unit not operating (Standby Mode); “outdoor ambient temperature”. ii. Unit operating; displays “compressor operating frequency”.
After 20 seconds on same parameter, the display will revert back to normal status.
If a system protection is active, first digit will display “status code”.
SW1 is not used. See Figure 31.

Figure 31
No. 0
1
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
Table 21

Point check content Outdoor unit capacity
Outdoor unit mode
Outdoor unit set compressor speed (Hz) T3 (outdoor coil temp.) (°F) T4 (outdoor ambient temp.) (°F) T5 (compressor discharge temp.) (°F) Th (compressor suction temp.) (°F) T3L(Condenser outlet temp.) (°F) Tf (module temp.) (°F ) Pe (evaporating pressure) (PSI) Pc (condensing pressure) (PSI) Tes ( target of the evaporating temp.) (only use for cooling mode) (°F) Te (evaporating temp.) (°F) Tcs target of the condensing temp. (only use for heatling mode) (°F) Tc (condensing temp.) (°F) Target of the compressor discharge superheat (only use for heating mode) (°F) Compressor discharge superheat (°F) Openings of EEV Outdoor Fan speed Compressor current (A) Power AC voltage Input (V) Compressor input dc voltage (V) Continuous running time of the compressor (min) Last Fault Code Software version T1 (Return air temp) (°F) T2 (Indoor coil temp) (°F) Indoor blower motor speed Ts (Estimated thermostat set point) (°F) Remark”–”

Example H3
2
66

Remark
H3=Heat pump 3 ton
0 standby 2 cooling 3 heating

Low Suction Pressure High Head Pressure

see Table 19
Only valid for 3T Only valid for 3T Only valid for 3T Only valid for 3T

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13.9 Control Board Overview
Outdoor Unit Control Board for 3 Ton Model

Installation Instructions

No. Function description

23 22 21 20 19 18 17 16 15 14 13

1. Compressor crankcase heater port 2. Reserve 3. Reversing valve port

4. Thermostat wire connections

12

5. Th sensor port

11

6. T3 T4 T3L sensor port

7. Pressure transducer port
10
8. T5 sensor port

9

9. Communication port (to indoor unit)

8

10. Electric expansive valve

24

7

11. Reserve

25

6

12. Reserve

13. High pressure switch port

26

5

14. SW2 FORCE BUTTON

15. SW3 CHECK BUTTON
4
16. Reserve

3

17. USB port

18. Reserve

19. SW5 Dip SWITCH: Defrost logic settings

20. SW4 Dip SWITCH: Control logic settings

21. LED

22. Reserve

23. ECM motor port

24. Compressor: W port
27
25. Compressor: V port

28

26. Compressor: U port

27. Power input

28. Power input

29 30

31 1 2

29. Non-replaceable Fuse 30. Ground port

31. Ground port

Figure 32

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| 27

Installation Instructions Indoor Unit Control Board for 3 Ton Model
6 7 8 9 10
Figure 33

5

No. Function description

1. Thermostat wire connection terminal

2. Electric Heat Kit E port

3. Thermostat wire port (to ODU board)

4. Transformer port

5. Blower motor port

6. T1, T2 sensor port
4
7. LED

3

8. Communication port (To ODU board)

9. Reserve

2

10. 3 Amp Replaceable Fuse

1

28 |

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Installation Instructions

13.10 Error Code Troubleshooting (ODU)

Error Code P1 P5 P3
Table 22

Description (Sensor) High pressure switch (HPS) protection Condenser coil temperature (T3) protection in cooling Compressor over current protection

P1 (High pressure switch (HPS) protection)

Diagnosis

Handling

Check whether the high pressure switch wires are seated normally
Yes

No Reseat the wires according to wiring diagram

Check whether high pressure No Replace high pressure switch switch is closed

Yes

Check whether indoor and No outdoor units are normal by filter and airflow
Yes

Exclude all fault reasons and restart

Cooling mode refers to P5

Figure 34

P5 (Condenser coil temperature (T3) protection in cooling)

Diagnosis

Handling

Check whether T3 is normal according toTable 34 (between

No

temperature and resistance)

Yes

Check whether outdoor unit motor is abnormal or whether Yes the outdoor condenser coil is blocked
No

Replace the T3 sensor
Replace the fan or remove all the blockage

Check whether there is short Yes Do something to avoid air

circuit in air outlet and inlet side

return short circuit

No

Check whether the charge is

correct by subcooling

No

according to installation guide

in charge mode when cooling

Yes

Adjust refrigerant charge

Check whether there is normal throttle
Yes

No Adjust or repair the EEV throttle

Figure 35

P3 (Compressor over current protection)

Diagnosis

Handling

Check whether outdoor unit motor is abnormal and the Yes outdoor condenser coil is blocked
No

Replace the fan or remove all the barriers

Check whether compressor No wiring is normal

Wire correctly according to the wiring diagram

Yes

Check whether compressor insulation resistance is greater

No

than 100K

Yes

Replace the compressor

Restart system and check whether the difference of high and low

No

pressure is more than 30 PSI after

compressor has run for 10 mins

Yes

Check whether the compressor current is more No than 15A for 2/3 ton when protected

Yes

Replace the compressor Replace the board
Replace the compressor

Figure 36

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

| 29

Installation Instructions

Error Code P0
Table 23

Description High module radiator temperature (TF) protection

P0 (High module radiator temperature (TF) protection)

Diagnosis

Handling

Check for dust or debris Yes blocking radiator

Clean all the dust and debris

No
Check if all screws are properly installed and if thermal paste is properly applied
Yes

No Follow board replacement instruction for correct steps

Restart system and check whether the fan and motor

No

Replace the fan and motor

can operate normally

Yes

Operate system and check No whether there`s the same fault
Yes

Operate normally

Figure 37

Error Code P2 H5 P4
Table 24

Description Low pressure (PT) Protection in cooling and heating System lockup, 5 times (P2) protection in 100 minutes High compressor discharge temperature(T5) protection

P4 (High compressor discharge temperature (T5) protection)

Diagnosis

Handling

Check whether the T5 is normal according to Table 35 (between

No

temperature and resistance)

Replace the T5 sensor

Yes
Check whether outdoor and indoor unit motor is abnormal Yes or whether coils (outdoor and indoor) are blocked
No

Check whether the charge is

correct by subcooling

No

according to design subcooling

force mode when in cooling

Yes

Check whether the EEV is

normal for throttle

No

(wire seated coil)

Yes

Replace the fan or remove all the barriers
Adjust the charge
Re-power and check again,if the same, replace the EEV.

Check whether the compressor is normal (abnormal noise,

No

abnormal vibration)

Yes

Replace the compressor

Figure 39

P2 (Low pressure (PT) Protection in cooling) H5 (System lockup, 5 times (P2) protection in 100 minutes)

Diagnosis

Handling

Do superheat and subcooling meet required values? (Refer No to Section 12 system charge adjustment)
Yes
Is the blower fan motor working properly? Is there any No blockage on filter? Are the EEV and outdoor fan motor working properly?
Yes
Is the pressure transducer working properly? Compare No the data between pressure measurement and No 9 (cooling) or No 10 (heating) values (by pressing the check button).
Yes

Adjust charge
Correct these issues and restart the system
Replace the pressure transducer

Figure 38

30 |

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

Error Code E4 H8 F1
Table 25

Description Temperature sensor fault (T3, T4, T5,Th, T3L) Pressure transducer (PT) fault High pressure switch (HPS) fault

E4 (Temperature sensor fault (T3, T4, T5, Th, T3L)

Diagnosis

Handling

Check whether sensor T3/T4/T5/Th/T3L are seated and normal (T4 for Heat Pump only)
Yes

No Reseat the sensor according to wiring diagram

Unplug the sensor, check

whether the resistance of

No

T3/T4/Th/T3L is in the range

of Table 34

Yes

Replace the fault T3/T4 Th/T3L sensor

Unplug the sensor, Check

No

whether the resistance of T5/Tf

Replace the fault T5/Tf sensor

is in the range of Table 35

Yes

Check whether the display the shows the same error code

No

when re-powered on

Yes

Keep running

Figure 40

H8 (Pressure transducer (PT) fault)

Diagnosis

Handling

Check whether pressure

No

transducer (PT) wiring are

seated and normal

Yes

Is the pressure transducer No working properly? Compare the data between pressure measurement and No 9 (cooling) or No 10 (heating) check point value (by pressing check button)
Yes

Wire according to the diagram correctly
Replace the pressure transducer

Check whether there is the No same fault
Yes

Keep running

Figure 41

Installation Instructions

F1 (High pressure switch (HPS) fault)

Diagnosis

Handling

Check whether high pressure No switch (HPS) wiring is seated and normal
Yes

Check whether the

No

resistance of HPS is close to

0K

Yes

Reseat wiring according to thewiring diagram
Replace high pressure switch

Check whether there is the No same fault
Yes

Keep running

Figure 42

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

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Installation Instructions

Error Code C3 E7
Table 26

Description Condenser coil sensor (T3) is seated fault in cooling Compressor discharge sensor (T5) is seated fault

C3 Condenser coil sensor (T3) is seated fault in cooling)

Diagnosis

Handling

Check whether condenser coil sensor (T3) is seated

No

to the condenser coil

Yes

Reseat the sensor to condenser coil

Check whether the T3/T4

sensors are connected

No

according to wiring diagram

Wire according to the wiring diagram correctly

Yes

Check whether the

No

resistance of T3/T4 is in

the range of Table 34

Yes

Check whether there are other heat sources around No T3/T4

Yes

Replace the fault T3/T4 sensor
Remove all the other heat sources

Check whether there is the No same fault
Yes

Keep running

Figure 43

E7 Compressor discharge sensor (T5) is seated fault)

Diagnosis

Handling

Check whether compressor

discharge sensor (T5) is

No

seated to the compressor

discharge line

Yes

Reseat the sensor to discharge tube

Check whether the sensor of T3/T5 are connected accord-

No

ing to wiring diagram

Yes

Wire according to the wiring diagram correctly

Check whether the resistance No

of T3/T5 is in the range of

Replace the fault T3/T5 sensor

Table 34 and Table 35

Yes

Check whether there are other No heat sources around T3/T5
Yes

Remove all the other heat sources

Check whether there is the No same fault

Keep running

Figure 44

Error Code E6
Table 27

Description DC fan motor fault

If the E6 error code appears occasionally, no action is necessary. The system will restart automatically after 6 minutes.

32 |

E6 DC fan motor fault)

Diagnosis

Handling

Check whether DC motor wiring is reliably connected No according to the wiring diagram
Yes

Reseat the wiring according to wiring diagram

Check whether outdoor coil air return is blocked

No Remove all the barriers

Yes

Check whether there is No

15V DC between the test

Replace the control board

point P & N

Yes

Check whether there is No the same fault

Keep running

Yes

Figure 45

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

Error Code E9 H0 E5
Table 28

Description EEPROM fault Communication fault in main control chip High/low voltage protection

If error codes E9/H0/E5 appear occasionally and after the system restarts and runs normally after the power supply is re-established, no action is necessary. Otherwise the system must be checked.

E9 (EEPROM fault) Diagnosis

Handling

Check whether the wiring is No Reseat the wiring according

connected normally

to wiring diagram

Yes

Restart to power on and check whether it is normal

No Reseat the wiring according to wiring diagram

Yes
No action is necessary. This fault may be caused by strong interference from the electric grid. The system will recover when the electric supply stabilizes.

The fault is still present
Replace the control board

Figure 46

Installation Instructions

E5 (High/low voltage protection)

Diagnosis

Handling

Check whether the power supply voltage is between

No

172-270V

Yes

Check whether the power wires are

connected firmly and whether the power supply wires diameter meets

No

the requirements from the

manufacturer

Yes

Make sure the power supply is within correct range
Replace the power supply wires or connect the power supply wires well

Restart to the power supply and check whether the

No

compressor operates normally

Replace the control board

Yes
Gauge and check whether there is 380V DC between the No terminals P & N when the compressor is running
Yes

Replace the control board

Check whether there is high voltage equipment nearby
No

Yes

Separate high-power equipment and power

supply

Figure 48

H0 (Communication fault in main control chip)

Diagnosis

Handling

Check whether the wiring is No Reseat the wiring according

connected normally

to wiring diagram

Yes

Restart to power on and check whether it is normal

No Replace the control board

Yes
No action is necessary. This fault may
be caused by strong interference from No
the electric grid. The system will recover when the electric supply stabilizes.

Replace the control board

Figure 47

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

| 33

Installation Instructions

Error Code L0-L9
Table 29

Description IPM module protection

When error codes L0-L9 appears occasionally, no action is necessary. The system will restart automatically after 6 minutes. Please follow the steps below if L0-L9 appears frequently.

Error Code AtL
Table 30

Description Ambient Temperature Limited

When the ambient temperature returns to within the operating range, the system will recover automatically.

L0-L9 ( IPM module protection)

Diagnosis

Handling

Check whether the power supply is stable

No

Correct the power supply

Yes

Check for blockages in refrigerant piping.

Yes

Clean the blockage

No

Check to see if there are any abnormal noises from the

Yes

compressor

Replace the compressor

No

Power off and wait at least 3 minutes before powering on. Yes
Check if the unit can run at
least 1 hour

Check the refrigerant charge and adjust

No L0-L9 issue happen again

No need to replace board

Check the winding resistance: 1. The resistance of two

No

windings (U, V, W) 2

2. The resistance between

compressor winding and

ground 10M

Yes

Replace control board

Replace compressor

Power on and check if the No problem has been resolved.
Yes
Run unit normally

Replace the unit

Figure 49

AtL (Ambient Temperature Limited)

Diagnosis

Handling

Check whether the ambient temperature is beyond the range Yes cooling: 23°F-125°F heating: -4°F-86°F
No

Normal

Check whether sensor T4 is seated normally (T4 for Heat Pump only)
Yes

No Reseat the sensor according to the wiring diagram

Unplug the sensor, and check whether the resistance of T4 is No within the operational range (Refer to Table 34)
Yes

Replace the faulty T3/T4 sensor

No action is necessary. restart the system.

Figure 50
Error Code /
Table 31

Description No display on control board

No display on ODU control board

Diagnosis

Handling

Restart the system and check if Yes the LED display is working
No

Check if the high voltage No power supply is stable
Yes

Pull out the ODU motor

Yes

connection, check if there is

any display

No

Pull out the pressure

Yes

transducer connection,

check if there is any display

No

Replace ODU board

Working properly
Correct power supply
Replace ODU motor Replace pressure transducer

Figure 51

34 |

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

Error Code Troubleshooting (IDU)

Number of flashes 4 5
Table 32

Description (Sensor) Temperature sensor fault (T1) Temperature sensor fault (T2)

4/5 Flashes (Temperature sensor fault)

Diagnosis

Handling

Check whether T1/T2 sensor No is seated normally

Yes

Unplug the sensor and measure the resistance to

Yes

ensure it’s neither 0 nor

No

Restart the unit to check if Yes the problem is resolved
No

Replace indoor control board

Reseat sensors Replace sensors
Finish

Figure 52

Installation Instructions

Number of flashes 6
Table 33

Description (Sensor) Communication error

6 Flashes (Communication error)

Diagnosis

Handling

Check if the communication wire is connected properly

No

Correct the wire connections

(Refer to Figure 32 and 33)

Yes

Check if ODU control board No LED display is working
Yes

Check if there is 230V power input, if yes, replace ODU board

Restart the system

Figure 53

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

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Installation Instructions

13.12 Temperature and Resistance Relationship Tables (for Sensors)

TEMP F -5 0 5 10 15 20 25 30 40 45 50 55 60 65 70 75 80 85

TEMP C -20.6 -17.8 -15.0 -12.2 -9.4 -6.7 -3.9 -1.1 4.4 7.2 10.0 12.8 15.6 18.3 21.1 23.9 26.7 29.4

RESISTANCE k 107.732 93.535 79.521 67.795 57.948 49.652 42.645 36.710 27.386 23.732 20.610 17.939 15.648 13.681 11.987 10.527 9.265 8.172

Table 34 for T3, T4, Th, T3L, T1, T2

VOLTS DC 4.65 4.60 4.54 4.47 4.39 4.30 4.21 4.10 3.86 3.73 3.59 3.45 3.30 3.15 2.99 2.83 2.67 2.52

TEMP F 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170

TEMP C 32.2 35.0 37.8 40.6 43.3 46.1 48.9 51.7 54.4 57.2 60.0 62.8 65.6 68.3 71.1 73.9 76.7

RESISTANCE k 7.225 6.401 5.683 5.057 4.509 4.028 3.606 3.233 2.902 2.610 2.350 2.119 1.914 1.731 1.574 1.416 1.276

VOLTS DC 2.36 2.21 2.07 1.93 1.79 1.67 1.55 1.43 1.32 1.22 1.13 1.04 0.96 0.88 0.82 0.75 0.68

36 |

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

13.13 Temperature and Resistance Relationship Tables (for T5)

TEMP F -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105

TEMP C -20.6 -17.8 -15.0 -12.2 -9.4 -6.7 -3.9 -1.1 1.7 4.4 7.2 10.0 12.8 15.6 18.3 21.1 23.9 26.7 29.4 32.2 35.0 37.8 40.6

110

43.3

115

46.1

120

48.9

125

51.7

130

54.4

135

57.2

Table 35 for T5

RESISTANCE k 600.134 505.551 427.463 362.739 308.891 265.398 227.481 195.601 168.707 146.695 127.258 110.707 96.572 84.465 74.411 65.408 57.634 50.904 45.258 40.152 35.699 31.807 28.398 25.506 22.861 20.529 18.47 16.708 15.085

VOLTS DC 4.93 4.92 4.91 4.89 4.87 4.85 4.83 4.80 4.77 4.74 4.70 4.66 4.61 4.56 4.51 4.45 4.39 4.32 4.24 4.16 4.08 3.99 3.89 3.80 3.70 3.59 3.48 3.37 3.26

TEMP F 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 245 250 255 260 265 270 275 280

TEMP C 60.0 62.8 65.6 68.3 71.1 73.9 76.7 79.4 82.2 85.0 87.8 90.6 93.3 96.1 98.9 101.7 104.4 107.2 110 112.8 115.6 118.3 121.1 123.9 126.7 129.4 132.2 135.0 137.8

Installation Instructions

RESISTANCE k 13.643 12.359 11.214 10.227 9.308 8.485 7.746 7.105 6.504 5.963 5.474 5.032 4.645 4.28 3.949 3.648 3.383 3.133 2.904 2.694 2.503 2.334 2.172 2.024 1.888 1.767 1.651 1.544 1.446

VOLTS DC 3.14 3.03 2.91 2.80 2.68 2.56 2.45 2.34 2.23 2.13 2.02 1.92 1.83 1.73 1.64 1.56 1.48 1.40 1.32 1.25 1.18 1.12 1.06 1.00 0.95 0.90 0.85 0.80 0.76

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

| 37

Installation Instructions

Wiring Diagram

Figure 54

1 2 Reserved 3 4 5 6

SW6-4 ON*

SW6-4 OFF

H MH M L H MH M L

38 |

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

Maintenance

For continuing high performance and to minimize possible equipment failure, periodic maintenance must be performed on this equipment.
14.1 Cleaning Precautions
WARNING: Any unit repairs must be performed by qualified service
personnel only.
WARNING: ELECTRICAL SHOCK Always turn off your heat pump and disconnect its power
supply before cleaning or maintenance.
CAUTION: When removing filter, do not touch metal parts in the unit.
The sharp metal edges can cut you.

Installation Instructions
14.2 Regular Maintenance
Your heat pump must be inspected regularly by a qualified service technician.

Inspect the air filter every ninety days or as often as needed. If blocked or obstructed, clean or replace at once.
Your annual system inspection must include: 2. Inspection and/or cleaning of the blower wheel housing and motor.
3. Inspection and cleaning of indoor and outdoor coils as required.
4. Inspection and/or cleaning of the indoor coil drain pan and drain lines, as well as auxiliary drain pan and lines.
5. Check all electrical wiring and connections. Correct as needed, referring to the wiring diagram. (Refer to Figure 54)
Online Help Resources Alternatively, please visit our Service & Support webpage to find FAQs, videos, service bulletins, and more; www.boschheatingcooling.com/service or use your cellphone to scan the code below.

NOTICE: Do not use chemicals or chemically treated cloths to clean
the unit .
Do not use benzene, paint thinner, polishing powder or other solvents to clean the unit.
Do not operate the system without a filter in place

Bosch 18 SEER2 Series Inverter Ducted Packaged Heat Pump – BTC 761703103 A (11.2022)

| 39

United States and Canada Bosch Thermotechnology Corp. 65 Grove St. Watertown, MA 02472
Tel: 866-642-3198 Fax: 954-776-5529 www.bosch- thermotechnology.us
BTC 761703103 A | 11.2022
Bosch Thermotechnology Corp. reserves the right to make changes without notice due to continuing engineering and technological advances.