Bosch IDS BOVB20 User manual

Installation Instructions
Split System Heat Pump
Bosch IDS BOVB20
IDS Connected Premium Condensing Units | 2 3 4 5 Ton Capacity | R410A
BTC 761701316 C / 02.2022

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
Table of Contents
1 Key to Symbols and Safety Instructions 4
1.1 Key to Symbols 4
1.2 Safety 4
1.2.1 Gateway Related Warnings 6
2 Bosch EasyAir Mobile App 7
3 Unit Location Considerations 7
3.1 Unit Dimensions 7
3.2 Refrigerant Piping Limits 8
3.3 Location Restrictions 9
4 Unit Preparation 10
4.1 Prepare the Unit for Installation 10
5 Setting the Unit 10
5.1 Pad Installation 10
5.2 Mounting Antenna 11
6 Refrigerant Line Considerations 12
6.1 Refrigerant Line and Service Valve Connection Sizes 12
6.2 Required Refrigerant Line Length 12
6.3 Refrigerant Line Insulation 12
6.4 Reuse Existing Refrigerant Lines 12
7 Refrigerant Line Routing 13
7.1 Precautions 13
8 Refrigerant Line Brazing 14
8.1 Braze The Refrigerant Lines 14
9 Refrigerant Line Leak Check 16
9.1 Check For Leaks 16
10 Evacuation 16
10.1 Evacuate the Refrigerant Lines and Indoor Coil 16
11 Service Valves 17
11.1 Open the Service Valves 17
12 Electrical - Low Voltage 18
12.1 Low Voltage Maximum Wire Length 18
12.2 Low Voltage Hook-Up Diagrams 18
12.3 Thermostat Wiring Diagrams 18
13 Electrical - High Voltage 22
13.1 High Voltage Power Supply 22
13.2 High Voltage Disconnect Switch 22
13.3 High Voltage Ground 22
14 Start Up 23
14.1 System Start Up 23
15 System Charge Adjustment 24
15.1 Charging: Weigh-In Method 24
15.2 Subcooling Charging And Refrigerant Adjustment In Cooling
(Above 55°F Outdoor Temp.) 24
16 System Operation and Troubleshooting 27
16.1 Control Logic Description 27
16.2 Sensors (Thermistors/Pressure Transducer) 27
16.3 Pressure Equalizer Valve (PEV) 27
16.4 Defrost Description 27
16.5 Compressor Crankcase Heater Description 28
16.6 Reversing Valve Operation 28
16.7 Protection Functions 28
16.8 Fault Code Table 29
16.9 Parameter Point Check Table 30
16.10 Control Board Overviews 31
16.11 Error Code Troubleshooting 33
16.12 Temperature and Resistance Relationship Tables (for Sensors) 42
16.13 Temperature and Resistance Relationship Tables (forT5&TfSensors) 43
17 Wiring Diagram 44
18 IDS2.1 Gateway Functionality 45
19 Care and Maintenance 46
19.1 Cleaning Precautions 46
19.2 Maintenance – Pre-Season Inspection 46

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
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
WARNING:ELECTRICALHAZARD380 VOLTS DC
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.
The manufacturer recommends installing only approved
matched indoor and outdoor systems. All of the manufacturer’s split
systems are AHRI rated only with TXV indoor systems. Some of the
benefits of installing approved matched indoor and outdoor split
systems are maximum efficiency, optimum performance and the best
overall system reliability.
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:
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.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
WARNING:HAZARDOUSVOLTAGE
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.
WARNING:REFRIGERANTOIL
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.
WARNING:HOTSURFACE
May cause minor to severe burning. Failure to follow this
Caution could result in property damage or personal injury.
Do not touch top of compressor.
CAUTION:CONTAINS REFRIGERANT
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:
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.
CAUTION: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.
WARNING:SERVICEVALVES
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 opening the Liquid Line Service valve. Turn valve stem
counterclockwise only until the stem contacts the rolled
edge.
WARNING:BRAZINGREQUIRED
Failure to inspect lines or use proper service tools may result
in equipment damage or personal injury. If using existing
refrigerant lines make certain that all joints are brazed, not
soldered.
WARNING:HIGHCURRENT LEAKAGE
Grounding is required before connecting electrical supply.
Failure to follow this warning could result in property
damage, severe personal injury, or death.
NOTICE:INDOORUNITREQUIRED
The indoor units must be matched with TXV. The model of
TXV can be changed according to the system capacity.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
1.2.1 Gateway Related Warnings
NOTICE:
This equipment has been tested and found to comply with
the limits for a Class B digital device, pursuant to Part 15
of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference in a
residential installation. This equipment generates uses
and can radiate radio frequency energy and, if not installed
and used in accordance with the instructions, may cause
harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more
of the following measures:
—Reorient or relocate the receiving antenna.
—Increase the separation between the equipment and
receiver.
—Connect the equipment into an outlet on a circuit
different from that to which the receiver is
connected.
—Consult the dealer or an experienced radio/TV
technician for help.
This device complies with part 15 of the FCC Rules. Operation is subject
to the following two conditions: (1) This device may not cause harmful
interference, and (2) this device must accept any interference received,
including interference that may cause undesired operation.
Changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate the
equipment.
NOTICE:
This device contains licence-exempt transmitter(s)/
receiver(s) that comply with Innovation, Science and
Economic Development Canada’s licence-exempt RSS(s).
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference, including
interference that may cause undesired operation of
the device.
WARNING: RF EXPOSURE
This equipment complies with FCC/ISED RF radiation
exposure limits set forth for an uncontrolled environment.
This equipment should be installed and operated with a
minimum distance of 8 inches (20 centimeters) between
the antenna and your body.
NOTICE: ICES STATEMENT
CAN ICES-3 (B)/NMB-3 (B)
This Class B digital apparatus complies with Canadian
ICES-003.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
2 Bosch EasyAir Mobile App
This Heat Pump has connectivity features which enable remote and on-site
monitoring of the system. Download the Bosch EasyAir app on your smartphone
and create an account to get started.
1. Download the Bosch EasyAir app on your smartphone by searching for
it in Google Play Store (for Android devices) or App Store (for iPhone).
Alternatively, you can scan this QR code with your phone’s camera:
Figure 1
Scan QR Code
2. Open the Bosch EasyAir app and create a profile. You can now use the
Bosch EasyAir app when starting up the system in Section 14.
Figure 2
3 Unit Location Considerations
3.1 Unit Dimensions
Models H x W x L (Inches)
BOVB36-20 24-15/16 x 29-1/8 x 29-1/8
BOVB60-20 33-3/16 x 29-1/8 x 29-1/8
Table 1
The unit’s weight values are on the carton box.
When mounting the outdoor unit on a roof, be sure the roof will support the unit’s
weight. Properly selected isolation is recommended to prevent sound or vibration
transmission to the building structure.
Figure 2
W
H
L
W
H
L

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
3.2 Refrigerant Piping Limits
System
Capacity
Model
Liquid
Line
Suction
Line
TotalEquivalent Length- Feet
25 50 75 100 125 150
InchO.D. Maximum Vertical Separation - Feet
2 Ton 3/8 * 3/4 Std. 25 50 45 40 30 25
5/8 Opt. 25 50 45 40 30 25
3 Ton 3/8 * 3/4 Std. 25 50 50 50 35 25
5/8 Opt. 25 50 50 50 35 25
4 Ton 3/8 * 7/8 Std. 25 50 50 40 30 25
3/4 Opt. 25 50 50 40 30 25
5 Ton 3/8 *
7/8 Std. 25 50 50 40 30 25
3/4 Opt. 25 50 50 40 30 25
1 1/8 Opt. 25 40 N/A N/A N/A N/A
Table 2
* Standard line size is recommended;
N/A: Application not recommended;
Refrigerant charge: refer to Sec. 14
Maximum line equivalent length = 150 feet.
Maximum vertical equivalent length = 50 feet.
Use only the line diameters indicated in Table 2.
If the suction linesets are greater than 50 feet, do not use a larger suction
line than recommended.
Figure 3
Standard Lineset
Lineset 150' Max
Line Length
50' Max
Line Lift
50' Max
Line Lift

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
3.3 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 sounds may be
objectionable.
Position unit to allow adequate space for unobstructed airflow, wiring, refrigerant
lines, and serviceability.
Allow a minimum of 12 in. clearance on one side of control board access panel to a
wall and a minimum of 24 in. on the adjacent side of control board access panel.
Maintain a distance of 24 in. between units.
Position unit where water, snow, or ice from roof or overhang cannot fall directly on
unit.
See Fig. 3 and Fig. 4.
Figure 4
Avoid Installations
Near Bedrooms
Min. 60" Unrestricted
Min. 12" to
Shrubbery
Min. 24"
Unrestricted
Access Panel
Figure 5
Min. 12" to
Shrubbery
Access Panel
Min. 24" to
Shrubbery
Cold climate considerations (heat pump only)
Precautions must be taken for units being installed in areas where
snow accumulation and prolonged below-freezing temperatures occur.
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 ice melted during defrost cycle prior to its refreezing. Ensure
that drain holes in unit base pan are not obstructed, which could prevent
the drainage of defrost water (Fig. 5).
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.
Figure 6
Min. 12"
Snow
barrier
3-12" Elevation
Snow legs
Pad
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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 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 away from the
waterfront.
Fencing or shrubbery may provide some shielding protection to the unit,
however minimum unit clearances must still be maintained.
Approximately every three months, wash the outdoor coil and any
exposed cabinet surfaces.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
4 Unit Preparation
4.1 Prepare the Unit for Installation
Check for damage and report promptly to the carrier any damage found to
the unit (Fig. 6).
The charge port can be used to ensure the refrigerant charge has been
retained during shipment.
Figure 7
5 Setting the Unit
5.1 Pad Installation
When installing the unit on a support pad, such as a concrete slab, consider the
following:
The pad must be at least 1-2” larger than the unit on all sides.
The pad must be separated from any structure.
The pad must be level.
The pad must be high enough above grade to allow for drainage.
The pad location must comply with National, State, and local codes.
These instructions are intended to provide a method to tie-down system
to cement slab as a securing procedure for high wind areas. Check local
codes for tie-down methods and protocols.
Figure 8
Figure 9
#7 X 3/8" Self-tapping screws
(Do not exceed 3/8" length screws!)
Detail A
See Section 2.1
for unit dimensions
See Detail A
Field-supplied brackets:
2" width, 1/16" thickness,
height as required.
1/4” Χ 1-1/2” Hex washer head concrete screws
(3/16” pilot hole needed. Pilot hole should be 1/4” deeper
than the fastener embedment)

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
5.2 Mounting Antenna
The antenna is used to transmit data to the cloud and will have the
strongest signal strength mounted furthest away from a wall or building.
1. Mount antenna on top of louver 3 (Refer to figure 10) on the left or right
side of the unit depending on which is furthest from a wall. Slide the
antenna downwards to mount the antenna and secure the cable using the 2
movable clips on the cable. Refer to figure 11.
Figure 10
33
2 2
1 1
IDS 2.1 ODU 5T Antenna Mounting IDS 2.1 ODU 3T Antenna Mounting
Mount antenna away from wall
Mount antenna away from wall
Figure 11
Clip antenna by sliding
downwards on louver
Secure cable to outdoor
unit with two clips
Building Wall

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
6 Refrigerant Line Considerations
6.1 Refrigerant Line and Service Valve Connection Sizes
Models SuctionLine LiquidLine SuctionLine
Connection
LiquidLine
Connection
Dimensionsin inches
BOVB36-20 3/4 3/8 3/4 3/8
BOVB60-20 7/8 3/8 7/8 3/8
Table 3
6.2 Required Refrigerant Line Length
Determine required line length (Fig. 9). Refer to Section 2.2.
Figure 12
Line Length
6.3 Refrigerant Line Insulation
The Suction Line must always be insulated. DO NOT allow the Liquid Line
and Suction Line to come in direct (metal to metal) contact.
Figure 13
Liquid Line Suction Line
Insulation
6.4 Reuse Existing Refrigerant Lines
CAUTION:MINORTOMODERATE BURNS
If using existing refrigerant lines, make certain that all joints
are brazed, not soldered.
For retrofit applications, where the existing refrigerant lines will be used, the
following precautions should be taken:
Ensure that the refrigerant lines are the correct size. Refer to Section 2.2
and Table 2.
Ensure that the refrigerant lines are free of leaks, acid, and oil.
The manufacturer recommends installing only approved matched indoor
and outdoor systems. All of the manufacturer’s split systems are AHRI
rated only with TXV indoor systems. The benefits of installing approved
matched indoor and outdoor split systems are maximum efficiency,
optimum performance and the best overall system reliability.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
7 Refrigerant Line Routing
7.1 Precautions
Take precautions to prevent noise within the building structure due to
vibration transmission from the refrigerant lines. For example:
When the refrigerant lines have to be fastened to floor joists or
other framing in a structure, use isolation type hangers.
Isolation hangers should also be used when refrigerant lines are
run in stud spaces or enclosed ceilings.
Where the refrigerant lines run through a wall or sill, they should
be insulated and isolated.
Isolate the lines from all ductwork.
Minimize the number of 90º turns.
Figure 14
Side View
8 Feet Maximum
8 Feet Maximum
Joist/Rafter
Isolator
Lineset
Secure Suction Line from joists using isolators every 8 ft. Secure Liquid Line
directly to Suction Line using tape, wire, or other appropriate method every 8 ft.
Isolation From Joist/Rafter
Figure 15
Side View
8 Feet Maximum
8 Feet Maximum
Wall
Isolator
Linesets
Secure Suction Line using isolators every 8 ft. Secure Liquid Line directly to
Suction Line using tape, wire, or other appropriate method every 8 ft.
Isolation On Walls
Comply with National, State, and local codes when isolating linesets
from joists, rafters, walls, or other structural elements.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
Figure 16
Isolator
Lineset
Ductwork
Suction Line
Sealant
Insulation
Wall
Isolation Through Wall DO NOT hang linesets from ductwork
8 Refrigerant Line Brazing
8.1 Braze The Refrigerant Lines
1. Remove caps or plugs. Use a deburring tool to deburr the pipe ends. Clean
both internal and external surfaces of the tubing using an emery cloth.
Figure 17

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Installation Instructions
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2. Remove the pressure tap cap from both service valves.
Figure 18
3. Purge the refrigerant lines and indoor coil with dry nitrogen.
Figure 19
This pipe
must have
a thimble
4. Wrap a wet rag around the valve body to avoid heat damage and continue the
dry nitrogen purge (Fig. 17).
Braze the refrigerant lines to the service valves.
Braze the filter drier to the Liquid Line.
All units come standard with a bi-flow filter drier. Braze the filter drier to
the liquid line, using caution not to push the refrigerant line too hard past
the stop within the filter drier (this could damage the drier).
Continue the dry nitrogen purge. Do not remove the wet rag until all brazing
is completed.
Remove the wet rag before stopping the dry nitrogen purge.
Figure 20
Shipped in package
field installed
3-4" from valve
5. Replace the pressure tap caps after the service valves have cooled.
Figure 21

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
9 Refrigerant Line Leak Check
9.1 Check For Leaks
1. Pressurize the refrigerant lines and evaporator coil to 150 PSIG using dry
nitrogen.
Figure 22
150 PSI
G
2. Check for leaks by using a soapy solution or bubbles at each brazed location.
Figure 23
10 Evacuation
10.1 Evacuate the Refrigerant Lines and Indoor Coil
Do not open the service valves until the refrigerant lines and indoor coil
leak check and evacuation are complete.
1. Evacuate until the micron gauge reads no higher than 350 microns, then
close the valve to the vacuum pump.
Figure 24
0350
Microns
ON OFF
2. Observe the micron gauge. Evacuation is complete if the micron gauge does
not rise above 500 microns in one (1) minute.
Once evacuation is complete, turn off the vacuum pump and micron gauge,
and close the valves on the manifold gauge set.
Figure 25
1MIN.

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Installation Instructions
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11 Service Valves
11.1 Open the Service Valves
WARNING:MODERATE TO SEVERE BURNS
Extreme caution should be exercised when opening the
Liquid Line Service Valve. Turn counterclockwise until
the valve stem just touches the rolled edge. No torque is
required. Failure to follow this warning will result in abrupt
release of system charge and may result in personal injury
and /or property damage.
Leak check and evacuation must be completed before opening the
service valves. The brazed lineset valves should be used for leak
checking and vacuuming. Using the separate suction port for this
process will result in loss of charge.
The Suction Service Valve must be opened first BEFORE opening the
Liquid Service Valve.
1. Remove Service Valve Cap (Fig. 23).
2. Fully insert hex wrench into the stem and back out counterclockwise until
valve stem just touches the rolled edge (approximately five (5) turns.)
3. Replace the Valve Stem Cap to prevent leaks. Tighten finger tight plus an
additional 1/6 turn.
4. Repeat STEPS 1 - 3 for Liquid Service Valve.
Figure 26
Cap
5/16" Hex Wrench
for Suction Service Valve
3/16" Hex Wrench
for Liquid Service Valve
Rolled Edge to
Captivate Stem
Hex Headed
Valve System
Service Port
Unit Side
of Service
Valve

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
12 Electrical - Low Voltage
12.1 Low Voltage Maximum Wire Length
Table 4 defines the maximum total length of low voltage wiring from the outdoor
unit, to the indoor unit, and to the thermostat.
24Volts- Wire size Max.Wire Length
18 AWG 150 Ft.
16 AWG 225 Ft.
14 AWG 300 Ft.
Table 4
12.2 Low Voltage Hook-Up Diagrams
Figure 27
Control
Board
Access
Panel
NOTES:
- Low voltage connection must be made inside the
outdoor unit control board access panel.
- There is no terminal block for low voltage connections,
wires must be spliced using field supplied wire nuts
- Field supplied wire nuts should be 22-16 gauge.
- Refer to unit wiring diagram for more information.
Low Voltage Unit Connections
12.3 Thermostat Wiring Diagrams
Be sure power supply agrees with equipment nameplate.
Power wiring and grounding of equipment must comply with local codes.
Low voltage wiring to be No. 18 AWG minimum conductor.
“- - - - - - - -” Field installed electric auxiliary heat connection
Single-stage auxiliary heating supported by 2H thermostat
Twin-stage auxiliary heating supported by 3H thermostat
W1: The first stage of field installed electric auxiliary heat.
W2: The second stage of field installed electric auxiliary heat.
The outdoor unit W signal is connected to the electric auxiliary heat or
the first stage electric auxiliary heat.
Figures 25-30 refer to thermostat wiring diagrams for the BOVB20 and
BVA20 manufacturer matched indoor and outdoor systems.
Dashed lines in the following thermostat wiring diagrams refer to optional
wiring (wiring for Passive Dehumidification Function and/OR Electric
Heat). For thermostat wiring please refer to the Owner’s Manual of the
thermostat.
B terminal to be connected with thermostat (O/B) wiring. Reversing valve
energizes in heating.

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
Figure 28
Y2
W/E
C
Y
CG
THERMOSTAT
INDOOR UNIT OUTDOOR UNIT
G
Y2
R
O/B
H/DH
W2
W1 CYBW
B
Dh Y1 R
GRAY PURPLE BROWN
BLUE
GREEN RED YELLOW WHITE
Support 3H and 2C thermostat
(This is the configuration of the BCC50)
WHITE/BLACK BROWN YELLOW BLUE WHITE
Note: Any time the electric heat
elements are active, the indoor fan
will run in high stage.
Thermostat Wiring Diagram for BOVB20/BVA20 Matched System
Figure 29
Wiring for 4H and 2C thermostat
(This is the configuration of the BCC100)
Y2
W/E
C
Y
C G
THERMOSTAT
INDOOR UNIT OUTDOOR UNIT
G
R
O/B
H/DH
W2
W1 CYBW
B
Dh Y1 R
W2
GRAY PURPLE
BROWN
BLUE GREEN RED YELLOW
WHITE
WHITE/BLACK BROWN YELLOW
BLUE
WHITE
Y2
Note: Any time the electric heat
elements are active, the indoor fan
will run in high stage.
Thermostat Wiring Diagram for BOVB20/BVA20 Matched System

20 |
Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
Figure 30
Y2
W/E
C
Y
CG
THERMOSTAT
INDOOR UNIT OUTDOOR UNIT
G
R
O/B
H/DH
W2
W1 CYBW
B
Dh Y1 R
GRAY PURPLE BROWN BLUE GREEN RED YELLOW WHITE
Wiring for 3H and 1C thermostat
WHITE/BLACK BROWN
YELLOW BLUE
WHITE
W2
Note: Because Y1 and Y2 are
jumped, the indoor fan will only run
in high stage.
Note: Any time the electric heat
elements are active, the indoor fan
will run in high stage.
Thermostat Wiring Diagram for BOVB20/BVA20 Matched System
Figure 31
Wiring for 2H and 2C thermostat
Note: Any time the electric heat
elements are active, the indoor fan
will run in high stage.
Y2
C
Y
C G
THERMOSTAT
INDOOR UNIT OUTDOOR UNIT
G
R
O/B
H/DH
W2
W1 CYBW
B
Dh Y1 R
GRAY PURPLE
BROWN
BLUE
GREEN
RED
YELLOW
BROWN
YELLOW BLUE
Y2
Thermostat Wiring Diagram for BOVB20/BVA20 Matched System