Bosch BRB-36HWD1N1-M18 User manual

Bosch Inverter Ducted Packaged Heat Pump
18.5 SEER Series (3 Ton Capacity)
R410A
Installation & Operation Manual
BTC 761701311 C | 04.2020 US

2 |Bosch Inverter Ducted Packaged Heat Pump 3 Ton Installation & Operation Manual
04.2020 | BTC 761701311 C
Data subject to change

Installation & Operation Manual Bosch Inverter Ducted Packaged Heat Pump 3 Ton | 3
BTC 761701311 C | 04.2020 Data subject to change
Table of Contents
1 Key to Symbols and Safety Instructions 4
1.1 Key to Symbols 4
1.2 Safety 4
2 Component Location 6
3 Dimensions 7
3.1 Unit Dimensions 7
3.2 Dimensions - Back and Bottom 8
3.3 Dimensions - Left and Top 9
4 Installation 10
4.1 Pre-Installation 10
4.2 Rigging and Lifting 10
4.3 Location Restrictions 10
4.4 Rooftop Installation - Curb Mounting 12
5 Airflow Performance 13
6 Indoor Fan Motor Function 14
7 Ductwork 15
8 Condensate Drain Connection 16
8.1 Install Drain Pipe 16
9 Air Filter (Not Factory-Installed) 16
10 Electrical Wiring 17
10.1 Power Wiring 17
10.2 Grounding 17
10.3 Control Wiring 17
11 Start Up 19
11.1 System Start Up 19
12 System Charge Adjustment 20
12.1 Charging: Weigh-In Method 20
12.2 Subcooling Charging and Refrigerant Adjustment In Cooling
(Above 55°F Outdoor Temp.) 20
13 System Operation and Troubleshooting 22
13.1 Control Logic Description 22
13.2 Sensors (Thermistors/Pressure Transducer) 22
13.3 Defrost Description 23
13.4 Compressor Crankcase Heater Description 23
13.5 Reversing Valve Operation 23
13.6 Protection Functions 24
13.7 Fault Code Table 25
13.8 Parameter Point Check Table 26
13.9 Control Board Overview 27
13.10 Error Code Troubleshooting (ODU) 29
13.11 Error Code Troubleshooting (IDU) 35
13.12 Temperature and Resistance Relationship Tables (for Sensors) 36
13.13 Temperature and Resistance Relationship Tables (for T5) 37
13.14 Wiring Diagram 38
14 Maintenance 39
14.1 Cleaning Precautions 39
14.2 Regular Maintenance 39

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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:HIGHVOLTAGE
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:ELECTRICALSHOCK
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:PERSONALINJURY/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:HOTSURFACE
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:HIGHPRESSURE
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:GROUNDINGREQUIRED
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:BURNHAZARD
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.
WARNING:ELECTRICALSHOCK
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.

6 |Bosch Inverter Ducted Packaged Heat Pump 3 Ton Installation & Operation Manual
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2 Component Location
Figure 1
Outdoor Fan
RV
T3
T3L
T2
PT
T4
Indoor Fan
HPS
EEV
T1
Service
Valves
T5
Th
Comp
Fusible
Plug
Component Descriptions Component Descriptions
HPS High pressure switch T3L Condensor outlet temp. sensor
PT Pressure transducer Tf Radiator temp. sensor
T1 Return air temp. sensor Th Comp. return temp. sensor
T2 Indoor coil temp. sensor EEV Electronic expansion valve
T3 Condenser temp. sensor RV Reversing valve
T4 Ambient temp. sensor COMP Compressor
T5 Comp. discharge temp. sensor FP Fusible Plug
Table 1 Component Descriptions

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3 Dimensions
3.1 Unit Dimensions
Figure 2
Front
Knock out hole
1-3/4" Dia
High voltage
conn. 1-1/8" Dia
Low voltage
conn. 7/8" Dia
Condensate drain
connection 3/4" NPT
(Trap required)
Heat Pump Model L W H A B
BRB-36HWD1N1-M18 50-11/16" 35-1/16" 46-13/16" 44-1/16" 11-3/4"
Table 2 Unit Dimensions
Heat Pump Model Net Weight Gross Weight
BRB-36HWD1N1-M18 412 lbs (187 kg) 432 lbs (196 kg)
Table 3 Unit Weights

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3.2 Dimensions - Back and Bottom
Figure 3
Bottom view
Back view
OPTIONAL
SUPPLY AIR
OPENING
OPTIONAL
RETURN AIR
OPENING
SUPPLY
DUCT
OPENING
RETURN
DUCT
OPENING
21-9/16"
4-5/16"
2-9/16"
7-7/8"
21-9/16"4-3/16"
Heat Pump Model C D E F G H
BRB-36HWD1N1-M18 47-13/16" 32-1/4" 9-15/16" 15-7/8" 15-3/4" 9-3/4"
Table 4 Dimensions - Back and Bottom

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3.3 Dimensions - Left and Top
Figure 4
Top view
11-3/4"
5-1/16"
Left side view
6-5/8" 6-5/8"

10 |Bosch Inverter Ducted Packaged Heat Pump 3 Ton Installation & Operation Manual
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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
Figure 5
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)
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).
Figure 6
Condensate drain side
Figure 7
Min 24"
Access Panel
Min. 60" Unrestricted
Min 24"
Access Panel
Avoid Installs
Near Bedrooms
A minimum clearance of 24" should be maintained adjacent to
all access/service panels. Refer to local code requirements for
additional clearance requirements.
Figure 8
Structure
Figure 9
Min 24"
Snow
barrier
3- 12" Elevation
Snow legs
pad
7
7
7
7
77
7
7
7
7
7
77
7
7
7
7
7
77
7
7
77
7
7
7
7
7
7
7
7
77
7
7
7
7
77
7
77
7
7
7
77
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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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.
Figure 10
A ― A
CC
A
BA
D
F
E
RETURN
AIR
SUPPLY
AIR
43-1/2"
12-5/8"
1 "
1"
INSULATION LAYER
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
Roof Curb Details
BCDEF
CURB 14-1/4" 14" 46-1/16" 16" 30-5/8"
Table 5 Roof Curb Details - inches
Figure 11
Insulation layer
1"
14-1/4"
46-1/16"
4-1/4"
12-5/8"
30-5/8"
14" 14" 1"
2"
2"
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.

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5 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
Motor
Speed *
SCFM
External Static Pressure-Inches W.C.[kPa]
0[0] 0.1[.02] 0.2[. 05] 0.3[.07] 0.4[.10] 0.5[.12] 0.6[.15] 0.7[.17] 0.8[.20]
36
Tap (1)
SCFM 925 807 723 658 / / / / /
Watts 114 120 126 130 / / / / /
Amps 1.07 1.12 1.17 1.19 / / / / /
Tap (2)
SCFM 1103 993 911 841 776 710 596 / /
Watts 162 169 175 181 187 193 197 / /
Amps 1.45 1.51 1.56 1.6 1.65 1.69 1.72 / /
Tap (3)
SCFM 1271 1185 1098 1031 968 819 767 709 648
Watts 251 256 262 268 273 281 285 289 293
Amps 2.17 2.21 2.26 2.3 2.34 2.39 2.42 2.45 2.48
Tap (4)
SCFM 1355 1310 1270 1180 1049 989 931 870 813
Watts 296 301 307 312 318 323 327 331 336
Amps 2.52 2.56 2.6 2.64 2.68 2.71 2.74 2.77 2.81
Tap (5)
SCFM 1522 1465 1364 1291 1231 1177 1121 1066 1017
Watts 426 432 438 443 448 452 456 460 466
Amps 3.49 3.54 3.58 3.62 3.65 3.68 3.7 3.74 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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6 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
SW6-4 SW6-1 SW6-2 High Mid-
high Mid Low
ON*
OFF OFF 2 2 1 1
OFF ON 3 2 2 1
ON* OFF* 4 3 2 1
ON 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.
SW6-4 SW6-1 SW6-2 High Mid-
high Mid Low
OFF
OFF OFF 2 / 1 /
OFF ON 3 / 1 /
ON OFF 4 / 2 /
ON 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* Heat: Anti-Cold Air Fan Delay via Temp Sensor
OFF Heat: Timed Fan Delay
Table 9
*Note: Default is ON
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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7 Ductwork
Field ductwork must comply with the National Fire Protection Association
NFPA 90A, NFPA 90B and any applicable local ordinance(s).
WARNING:FIREHAZARDANDCARBONMONOXIDE
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.
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.
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.
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.
Be sure to note supply and return openings. Refer to Figure 3
for information concerning supply and return air duct
dimensions.
Figure 13
Return Air
Supply Air
Roof Flashing
Angle Iron
Frame
Rooftop Installation - Frame Mounting
Figure 14
SHEET METAL
SCREWS
RETURN AIR
PANEL
SUPPLY AIR
PANEL
Note: Refer to downflow conversion instructions provided with the unit
Figure 15
Roof Flashing
Return Air Supply Air
Roof Flashing
Angle Iron
Frame
Typical Rooftop Downflow Application with Frame

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8 Condensate Drain Connection
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.
Figure 16
1in.(25mm)min
2in.(51mm)min
TRAP
OUTLET
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.
9 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:FIREHAZARD
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.
Heat Pump Model No. Size Recommended
BRB-36HWD1N1-M18 1 16"x10"x1"
Table 10

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10 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.
Figure 17
Indoor Control
Board
High voltage power supply
L1 L 2
Control wiring
CY1 Y2 RB/O
GDH W2 W1

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Data subject to change
Figure 18
THERMOSTAT UNIT CONTROL BOARD
TERMINAL STRIP
R
C
Y1
Y2
G
W1
B
W2
R
C
Y
Y2
G
W/E
O/B
H/DH Dh
GREEN
BLUE
WHITE
GRAY
PURPLE
YELLOW
BROWN
RED R
C
Y1
Y2
G
W1
B
W2
R
C
Y
Y2
G
W/E
O/B
H/DH Dh
W2
GREEN
BLUE
WHITE
WHITE/BLACK
GRAY
PURPLE
YELLOW
BROWN
RED
R
C
Y1
Y2
G
W1
B
W2
R
C
Y
G
W/E
O/B
H/DH Dh
W2
GREEN
BLUE
WHITE
WHITE/BLACK
GRAY
YELLOW
BROWN
RED R
C
Y1
Y2
G
W1
B
W2
R
C
Y
Y2
G
O/B
H/DH Dh
GREEN
BLUE
GRAY
PURPLE
YELLOW
BROWN
RED
R
C
Y1
Y2
G
W1
B
W2
R
C
Y
G
O/B
H/DH Dh
GREEN
BLUE
GRAY
YELLOW
BROWN
RED R
C
Y1
Y2
G
W1
B
W2
R
C
Y
G
O/B
H/DH Dh
W/E
GREEN
BLUE
WHITE
GRAY
YELLOW
BROWN
RED
Support 3H and 2C thermostat Support 4H and 2C thermostat
THERMOSTAT UNIT CONTROL BOARD
TERMINAL STRIP
Support 3H and 1C thermostat Support 2H and 2C thermostat
THERMOSTAT UNIT CONTROL BOARD
TERMINAL STRIP THERMOSTAT UNIT CONTROL BOARD TERMINAL STRIP
THERMOSTAT UNIT CONTROL BOARD
TERMINAL STRIP THERMOSTAT UNIT CONTROL BOARD TERMINAL STRIP
Support 1H and 1C thermostat Support 2H and 1C thermostat
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.
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
reversing valve energizes in heating.

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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.
Size
(Tons)
Voltage
- Phase -
Frequency
Compressors
(each)
OD Fan
Motors
(each)
Supply
Blower
Motor
Unit Circuit
RLA LRA FLA FLA MCA¹
(Amps)
Max Fuse²/
Breaker³ Size
(Amps)
36
(3)
208/230-
1-60 19A 52A 1.4A 3.5A 28.7 45
Table 11 Electrical Data Without Electric Heat
Heater Circuit
Dual Point Single Point
Model
kW
208/
240
Stages FLA
(Amps)
MCA¹
(Amps)
Max Fuse²/
Breaker³
Size
(Amps)*
MCA
(AMPS)
Max Fuse²/
Breaker³
Size
(Amps)**
EHK-05J 3.8/5 1 18.1/20.8 23/26 25/30 52/55 60/60
EHK-08J 5.6/7.5 1 27.1/31.3 34/40 35/40 63/68 70/70
EHK-10J 7.5/10.0 1 36.1/41.7 46/53 50/60 74/81 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).
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.
11 Start Up
11.1 System Start Up
1. Ensure Sections 4, 5, 6, 7, and 8 have been completed.
2. Set System Thermostat to OFF.
Figure 19
3. Turn on disconnect to apply power to the indoor and outdoor units.
Figure 20
ON
OFF
4. Wait one (1) hour before starting the unit if compressor crankcase
heater is used and the outdoor ambient temperature is below 70 °F.
Figure 21
60 MIN.
5. Set system thermostat to ON.
Figure 22

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12 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.
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 Refrigerant Charge (lb-oz)
BRB-36HWD1N1-M18 7-8
Table 13
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.
Figure 23
55ºF
Outdoor Temp1
120ºF
Outdoor
Temperature
Above 55ºF
55ºF
Outdoor Temp2
Outdoor
Temperature
Below 55ºF
For best results the indoor temperature should be kept between 70°F to
80°F.
Figure 24
80 ºF
70ºF
Indoor Temp
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.
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.
Figure 26
20 MIN.
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