Bosch Singular 4000 User manual

User Manual
Gas Condensing Combi Boilers
Singular
Singular 4000 | Singular 5200
BTC 439003302 A / 03.2021
WARNING:
If the information in these instructions are not followed exactly, a fire or explo-
sion may result causing property damage, personal injury or death.
WARNING:
Do not store or use gasoline or other flammable vapors and liquids in the vicinity
of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
—Do not try to light any appliance.
—Do not touch any electrical switch; do not use any phone in your building.
—Immediately call your gas supplier from a neighbor’s phone. Follow the gas
supplier’s instructions.
—If you cannot reach your gas supplier, call the fire department.
WARNING:
Improper installation, adjustment, alteration, service or maintenance can cause
property damage, personal injury (exposure to hazardous materials)* or loss of
life. Refer to the user's information manual provided with this boiler. Installation
and service must be performed by a qualified installer, service agency or the gas
supplier who must read and follow the supplied instructions before installing,
servicing, or removing this boiler. This boiler contains materials that have been
identified as carcinogenic, or possibly carcinogenic, to humans.
This boiler must be installed in accordance with local, state, and federal codes.
In the absence of such requirements, then to the latest edition of the National
Fuel Gas Code, ANSI Z223.1./NFPA 54. In Canada, installation must be in
accordance with the requirements of CAN/CSA B149.1, Natural Gas and
Propane Installation Code.

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Table of Contents
1 Key to Symbols and Safety Instructions 4
1.1 Key to Symbols 4
1.2 Safety 4
2 Front Panel 6
2.1 Digital Display and Icons 6
2.2 Buttons 6
3 Operating the Boiler 7
3.1 Turning the Boiler On or Off 7
3.2 Setting the Space Heating Temperature 7
3.3 Setting the DHW (Domestic Hot Water) Temperature 8
3.4 Viewing Basic Information 8
3.4.1 H0 mode 9
3.4.2 H1 mode 9
3.4.3 H2 mode 9
3.4.4 H3 mode 9
3.4.5 H4 mode 10
3.4.6 H5 mode 10
3.4.7 H6 mode 10
3.4.8 H7 mode 10
3.4.9 H8 mode 11
3.4.10 H9 mode 11
3.4.11 HA mode 11
3.4.12 HB mode 11
4 Inspection and Maintenance 12
4.1 Draining the Boiler 12
4.2 Cleaning the Cold Water Inlet Filter 14
4.3 Cleaning the Air Intake Filter 14
4.4 Protecting the Boiler from Freezing 15
4.5 Maintenance Schedules 15
4.5.1 Owner Maintenance 15
4.5.2 Service Technician Maintenance 15
5 Troubleshooting 17
5.1 Basic Problems 17
5.2 Error Codes 18

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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
WARNING:FIRE,EXPLOSION
Vapors from flammable liquids can explode and/or catch fire
causing death or severe burns.
Keep flammable products far away from the boiler and store
them in approved containers. Keep the containers tightly
closed and out of the reach of children.
The boiler has a main burner flame that can come on at any
time and will ignite flammable vapors.
Vapors cannot be seen and are heavier than air. They can
travel long distances along the ground and can be carried
from other rooms to the boiler’s main burner flame by air
current.
WARNING:SCALDHAZARD
Water temperature over 125°F can cause severe burns or
death from scalding.
Children, the disabled and the elderly are at highest risk of
being scalded.
Test water before bathing or showering.
Temperature TimetoProduceSerious Burn
120 °F (48 °C) More than 5 minutes
125 °F (51 °C) 1.5 to 2 minutes
130 °F (54 °C) Approx. 30 seconds
135 °F (57 °C) Approx. 10 seconds
140 °F (60 °C) Less than 5 seconds
145 °F (62 °C) Less than 3 seconds
150 °F (65 °C) Approx. 1.5 seconds
155 °F (68 °C) Approx. 1 second
Table 1
WARNING:FIRE,EXPLOSION
Do not store combustibles, such as papers or laundry, near
the boiler or venting system.
Do not store or use gasoline or other flammable liquids near
this boiler.
Do not store or use compressed gases, such as hair sprays
or spray paints, near the boiler or venting system, including
the vent termination.

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WARNING:HAZARDOUSVOLTAGE
Do not remove the front cover unless the power to the boiler
is turned off or disconnected.
Do not touch the internal components of the boiler or the
power cord with wet hands.
WARNING:FIRE,CARBONMONOXIDE
Do not operate the boiler with the front cover opened.
Do not operate the boiler without proper venting.
Do not place anything in or around the vent terminals that
could obstruct the air flow in or out of the boiler.
WARNING:FIRE,EXPLOSION
Have your installer or plumber show you the location of the
gas shut off valve and demonstrate how to close the valve. If
the boiler is damaged as a result of overheating, fire, flood,
or any other reason, close the manual shut off valve and do
not operate the boiler again until it has been inspected by a
qualified technician.
WARNING:FIRE,EXPLOSION
Should overheating occur or if the gas supply fails to shut
off, turn off the manual gas shut off valve.
WARNING:PERSONALINJURY,PROPERTY DAMAGE
Do not allow children to operate or have access to the boiler.
WARNING:IMPROPEROR DANGEROUSOPERATION
Immediately call a qualified service technician to inspect the
appliance and replace any part of the control system and/or
any gas control which has been immersed in water.
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.
WARNING:PERSONALINJURY,PROPERTY DAMAGE
Do not operate the boiler if you suspect something might be
wrong with it.
CAUTION:INTENDEDUSE
Do not use the boiler for anything other than its intended
purpose, as described in this manual.
WARNING:IMPROPEROR DANGEROUSOPERATION
Do not use unapproved replacement or accessory parts.
When servicing the controls, label all wires prior to
disconnecting them to prevent wiring errors.
Do not attempt to repair or replace any part of the boiler,
unless it is specifically recommended in this manual. For all
other service, contact an authorized technician or licensed
professional. Improper adjustments, alterations, service, or
maintenance may lead to property damage, personal injury,
or death and will void your warranty.
NOTICE:BOILERDAMAGE
Do not turn on the boiler unless the water and gas supplies
are fully opened. Failure to do so may damage the boiler.
This boiler has been approved for use in the USA and Canada only.
Using the boiler in any other country will void the manufacturer's
warranty.

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2 Front Panel
2.1 Digital Display and Icons
The digital display and icons on the front panel provide important information
required for the operation of the boiler. Refer to the table below for detailed
information.
Figure 1
A
B
C
D
E
F
G
H
I
Icon Description
ADigital display
Displays water temperature, error codes, etc.
BSpace heating mode
Indicates space heating mode operation.
CDHW mode
Indicates DHW mode operation.
DPressure
Indicates the pressure in the boiler.
ERPM
Indicates revolutions per minute (RPM).
FFreeze protection mode
Indicates freeze protection mode operation.
GOutdoor reset mode
Indicates ambient temperature sensor operation.
HCombustion
Indicates gas burner operation.
IError
Indicates error.
Table 2
2.2 Buttons
Using the buttons on the front panel, you can turn the boiler on or off, adjust the
water temperature, and change modes to monitor the operation status. Refer to the
table below for detailed information.
Figure 2
A
B
D
C
Icon Description
APower
Turns the boiler on or off.
BMode
Changes the mode.
CUP
Increases the temperature.
DDown
Decreases the temperature.
Table 3

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3 Operating the Boiler
3.1 Turning the Boiler On or Off
To turn the Boiler on or off, press the button.
Figure 3
When the boiler is on, the water temperature which has been set recently will
appear on the digital display.
3.2 Setting the Space Heating Temperature
WARNING:SCALDHAZARD
If your household includes children, or elderly or disabled
individuals, consider using a lower temperature setting.
To set the space heating water temperature:
1. Press the MODE button until the icon turns on.
Figure 4
2. Press the or buttons until the desired temperature appears on the
digital display.
Figure 5
Temperaturerange Adjusting the water temperature
82–180°F (Fahrenheit mode) 2°F increments
27–82°C (Celsius mode) 1°C increments
Table 4

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3.3 Setting the DHW (Domestic Hot Water) Temperature
WARNING:
Water above 120°F (50°C) can cause instant scalding,
severe burns, or death.
To adjust the water temperature:
1. Press the Mode button until the icon turns on.
Figure 6
2. Press the or buttons until the desired temperature appears on the
display.
Figure 7
Temperaturerange Adjusting the water temperature
82–180°F (Fahrenheit mode)
31–50°C (Celsius mode) 2°F increments 1°C increments (31–45°C) & 46, 48, 50°C
130°F, 140°F
55°C, 60°C 10°F or 5°C increments
Table 5
To change the temperature over 120°F, hold down button for 5
seconds to unlock.
3.4 Viewing Basic Information
To turn the boiler on, press the button.
Figure 8
To view information about the boiler, press the MODE and buttons for 5
seconds.
Figure 9
Press the MODE button to switch between the information types.

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3.4.1 H0 mode
This is the mode for checking the previous error.
H0 and the previous error (example: A6) will be displayed repeatedly on
the screen.
Figure 10
3.4.2 H1 mode
This is the mode for checking the most recent error.
H1 and the most recent error (Example : A2) will be displayed repeatedly
on the screen.
Figure 11
3.4.3 H2 mode
This is the mode for checking the current error.
H2 and the current error (Example : A3) will be displayed repeatedly on
the screen.
Figure 12
3.4.4 H3 mode
This is the mode for checking the current pressure in the system.
H3 and the current pressure in the boiler (Example : 25) will be displayed
repeatedly on the screen.
The pressure unit is PSI.
Figure 13

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3.4.5 H4 mode
This is the mode for checking the current number of revolutions of the fan.
H4 and the current number of revolutions of the fan (Example : 3600) will
be displayed repeatedly on the screen.
The unit is rpm.
Figure 14
3.4.6 H5 mode
This is the mode for checking the output voltage of the fan.
H5 and the output voltage (Example : C5) will be displayed repeatedly on
the screen.
Figure 15
3.4.7 H6 mode
This is the mode for checking the current exhaust gas temperature.
H6 and the current exhaust gas temperature (example: 120) will be
displayed repeatedly on the screen.
The unit is °F.
Figure 16
3.4.8 H7 mode
This is the mode for checking the current hot water temperature.
H7 and the hot water temperature (example: 100) will be displayed
repeatedly on the screen.
The unit is °F.
Figure 17

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3.4.9 H8 mode
This is the mode for checking the current ambient temperature.
H8 and the current ambient temperature (example: 25) will be displayed
repeatedly on the screen.
The unit is °F.
Figure 18
3.4.10 H9 mode
This is the mode for checking the return temperature of the boiler.
H9 and the return temperature (example: 120) will be displayed
repeatedly on the screen.
The unit is °F.
Figure 19
3.4.11 HA mode
This is the mode for checking the hot water and heating modes.
HA and the heating mode or the hot water mode (example: FF or 00) will
be displayed repeatedly on the screen.
FF is the current hot water mode, and 00 is the heating mode.
Figure 20
3.4.12 HB mode
This is the mode for checking the current PCB version (example: 1.0).
HB and the PCB version will be displayed repeatedly on the screen.
Figure 21

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4 Inspection and Maintenance
Annual service and maintenance is required for the safe and long service life of the
appliance, for efficient and economical operation, and to keep the environmental
impact as low as possible. Owners/operators are encouraged to sign a service and
maintenance contract with a trained and certified installer for annual servicing and
maintenance of the boiler.
WARNING:ELECTRICSHOCK HAZARD
Always disconnect the appliance from the main power
supply before performing any work. Disconnect the
emergency shutoff switch or disengage the heating system
circuit breaker. Take measures to prevent accidental
re-connection.
WARNING:SCALDHAZARD
The boiler may remain hot for few minutes after it is turned
off. Wait until the boiler has cooled down before cleaning to
prevent burns.
WARNING:SCALDHAZARD
The boiler may remain hot for few minutes after it is turned
off. Wait until the boiler has cooled down before cleaning to
prevent burns.
WARNING:SCALDHAZARD
The boiler may remain hot for few minutes after it is turned
off. Wait until the boiler has cooled down before cleaning to
prevent burns.
WARNING:EXPLOSION!
Close the gas supply shutoff valve prior to working on the
gas train.
Check for gas leaks after carrying out work on the gas train.
WARNING:RISKOF FLUE GAS POISONING
Check for leaks after carrying out work on the venting
system.
NOTICE:INSUFFICIENTANTIFREEZECAN ACCELERATE CORROSION
Frost protection level has to be checked annually during the
regular scheduled maintenance of the condensing boiler.
4.1 Draining the Boiler
To perform maintenance tasks or to prevent the boiler from freezing when it will not
be used for an extended period, the boiler must be drained.
To drain the boiler:
1. Press the button to turn off the boiler.
2. Disconnect the power supply to the boiler.
3. Turn of the gas valve.
Figure 22
Gas
4. Turn off the water supply valve on the inlet to the boiler.
Figure 23
Hot waterCold water
If there is no water supply valve, turn off the water supply at the water
main.

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5. Remove the boiler front cover by loosening the 2 Phillips screws securing it
to the case.
Figure 24
1
1
2
2
6. Open the drain valve.
Figure 25
7. Remove the strainer from the bottom of the boiler.
Figure 26
8. Close the drain valve when the water is completely drained.
9. Remove the cold water inlet filter.
10. Allow the residual water to drain from the boiler.
11. When the water is completely drained, reinsert the cold water inlet filter and
close the drain valve.
Follow the steps in reverse order to refll the boiler. Be careful not to lose
the drain plug.

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4.2 Cleaning the Cold Water Inlet Filter
To clean the cold water inlet filter:
1. Drain the boiler. Refer to " Draining the Boiler " on page 12.
2. Remove the cold water inlet filter from the boiler.
Figure 27
3. Rinse the cold water inlet filter with clean running water.
4. Reinsert the cold water inlet filter.
5. Refill the boiler. Refer to " Draining the Boiler " on page 12.
4.3 Cleaning the Air Intake Filter
To maintain the boiler properly, clean the air intake filter every 2–3 months. If the
air intake filter is clogged by dust or lint, the boiler will cease to operate or error can
occur.
To clean the air intake filter:
1. Press the button to turn off the boiler.
2. Disconnect the power supply to the boiler.
3. Remove the boiler front cover by loosening the 2 Phillips screws securing it
to the case.
Figure 28
1
1
2
2
4. Remove the air intake filter located under the air intake connector.
Figure 29
Air intake lter
5. Rinse the air intake filter with clean running water.
6. Dry the air intake filter completely.
7. Reinsert the air intake filter and replace the front cover.

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4.4 Protecting the Boiler from Freezing
NOTICE:BOILERDAMAGE,PROPERTY DAMAGE
To protect the boiler from freezing, recommend the use of
a direct vent exhaust and intake system. Ensure that the
exhaust vent pipe and the air intake pipe are both connected
directly from the collars on the top of the boiler to the
outdoors. This type of vent system minimizes air movement
within the boiler.
Freezing damage usually occurs due to back-drafting
caused by negative pressure in the building. This is not a
manufacturing defect, and therefore, Bosch will not warrant
any damage due to freezing. The installer is responsible
for ensuring that there is sufficient make-up air to avoid
such a situation, and the owner is responsible for ensuring
protection against freezing.
To protect the boiler from freezing, follow these guidelines:
Do not unplug the power supply cord, except for routine maintenance. The
boiler has a freeze protection function that warms up the boiler. The freeze
protection function will operate regardless of whether or not the front
panel isturned on or off, as long as the power supply is still connected.
If the power or gas supply must be disconnected for an extended period,
drain the boiler.
Protect and insulate all water pipes, including the condensate trap drain
line, from freezing.
If the boiler will not be used for an extended period of time, drain the
boiler.
If you suspect that the boiler is frozen, contact an authorized technician
or licensed professional.
4.5 Maintenance Schedules
WARNING:
A qualified technician must inspect the boiler at the
beginning of every heating season and/or when there is a
problem.
4.5.1 Owner Maintenance
Frequency Task
Daily
Check that the area where the boiler is installed is free of
combustible/flammable material and air-contaminants.
Visually inspect the exterior of the boiler.
Monthly
Inspect the condensate trap and the PVC fittings.
Visually inspect the piping (water and gas) for leaks.
Visually inspect the vent piping for signs of leakage and
blockage.
Every 6
Months
Inspect the piping (water and gas) for leaks.
Inspect the vent piping for leakage and blockage.
Test to make sure the pressure relief valve is operating
properly.
Table 6
4.5.2 Service Technician Maintenance
WARNING:PERSONAL INJURY OR DEATH.
Failure to inspect and properly maintain and repair the boiler
can result in severe personal injury or death.
Frequency Task
Every
Year
Inspect the interior of the boiler.
Clean the condensate trap and fill with fresh water.
Clean the air intake filter.
Check for leaks (gas, water, flue, and condensate).
Check the system pressure (gas, and water).
Check ignition and flame rod.
Check wiring connections.
Combustion analysis.
Table 7

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WARNING:
Follow the service and maintenance procedures given
throughout this manual and in component literature
shipped with the boiler. Failure to perform the service and
maintenance could result in damage to the boiler or system.
Failure to follow the directions in this manual and
component literature could result in severe personal injury,
death, or substantial property damage.
The boiler must be inspected annually by a qualified service
agency. In addition, the maintenance and care of the boiler
must be performed to assure maximum boiler efficiency
and reliability. Failure to service and maintain the boiler and
system could result in equipment failure.
Electrical shock hazard – Turn off power to the boiler
before any service operation on the boiler except as noted
otherwise in this instruction manual. Failure to turn off
electrical power could result in electrical shock, causing
severe personal injury or death.
Addressing the Reported Problems
Inspect any problems reported by the owner and correct before
proceeding.
Inspecting the Installation Area
1. Verify that boiler area is free of any combustible materials, gasoline and other
flammable vapors and liquids.
2. Verify that air intake area is free of any of the contaminants listed in
Installation Manual. If any of these are present in the boiler intake air
vicinity, they must be removed (pg. 28 of the Installation Manual, "Installing
Venting"). If they cannot be removed, reinstall the air and vent lines per the
Installation Manual.
Inspecting the Boiler Interior
1. Remove the front cover and inspect the interior of the boiler.
2. Vacuum any sediment from inside the boiler and components. Remove any
obstructions.
Cleaning the Condensate Trap
1. Inspect the condensate drain line, condensate fittings, and condensate trap.
2. Remove any sediment in the trap.
3. Fill
Checking the Flue Vent System and Air Piping
1. Visually inspect the entire flue gas venting system and air piping for blockage,
deterioration or leakage. Repair any joints that show signs of leakage. Verify
that air inlet pipe is connected and properly sealed (if installed).
2. Verify that boiler vent discharge and air intake are clean and free of
obstructions.

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5 Troubleshooting
5.1 Basic Problems
If there is a problem with the boiler, refer to the following table for possible
remedies. For minor problems, turning the boiler off and then turning back on may
resolve the situation. If turning the boiler off and on and attempting the remedies
Category Problem Possible Cause(s) What to Do
Initial
operation
Boiler does not ignite. Are the gas and water pipes connected properly? 1. Check for correct plumbing or crossed piping to the unit.
Unit attempts to ignite
but fails
Is there air in the gas line?
Is the gas supply pressure sufficient?
1. Turn off the boiler and then turn it back on.
2. Have your installing contractor check the gas supply
pressure.
3. Ensure the boiler is powered by 120 V-1 PH-60 Hz.
Temperature
Space heating side
malfunction
Is the setting temperature too low? 1. Check the boiler’s temperature setting. See "Operating the
Boiler" on page 7.
Is there power to the system, or is the system in
stand by?
1. Make sure the power is on, and plugged into the outlet with
the correct voltage. Press the Power button and raise the
setting temperature. Make sure the boiler is turned on.
Hot water is not produced
when a faucet is opened.
Are the gas and water supply valves fully open?
Is the water supply cut off to the household?
Is gas being provided by the gas meter?
Is there enough gas (for LP) in the tank?
Is the water inlet filter clogged?
Is the power button turned on?
1. Fully open the gas and water supply valves.
2. Check the water inlet filter for debris.
3. Check the power status of the boiler.
No water is available
when a faucet is opened.
Is the water supply cut off?
Is the boiler frozen?
Are the pipes frozen?
1. Open the cold water supply.
2. Check if the boiler and/or the pipes are frozen.
The hot water is not at
the correct temperature. Is the hot water faucet sufficiently open? 1. Fully open the hot water faucet.
Water takes a long time to
become hot after opening
the hot water faucet.
Have you allowed enough time for the cold water in
the pipes to drain out?
1. Even though the unit may be operating properly, the cold
water contained in the piping will need to flow through the
faucet before the hot water can reach the faucet. Wait for
several minutes.
The water is too hot. Are the gas and cold water supply valves fully open?
Is the water temperature setting appropriate?
1. If the cold water supply temperature is too high, it is
possible for the temperature to be higher than the
temperature set on the front panel. Decrease the water
temperature on the front panel.
2. If only a small amount of hot water is required, it is possible
for the temperature to be higher than the temperature set
on the front panel. Decrease the water temperature on the
front panel.
3. If the cold water supply passes through a solar preheating
system, it passes for the delivered water temperature to be
higher than the temperature set on the front panel.
The water is not hot
enough.
Are the gas and cold water supply valves fully open?
Is the water temperature setting correct?"
1. Fully open the gas and cold water supply valves.
2. Check the water temperature setting.
Fluctuation in hot water
temperature. Is the water inlet filter clogged? 1. Clean the water inlet filter for debris.
Table 8
suggested below do not resolve the problem, contact an authorized technician,
licensed professional, or technical support at 1-866-642-3198.

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5.2 Error Codes
If an error code appears on the digital display, refer to the following chart for the
reason, and a possible remedy for the situation. If the situation requires more
support please contact Bosch at 866-642-3198.
ErrorCode Cause Self-diagnosis/Action
A2 Abnormal operation: FAN
1. Clean the intake air filter.
2. Check the fan connector.
3. Contact original installer or licensed professional.
A3 Abnormal operation: Pump 1. Contact original installer or licensed professional.
A4 Overheating of heat exchanger 1. Turn off the system for at least 30 minutes, and then restart it.
2. Contact original installer or licensed professional.
A5 Low water pressure 1. Water supplementation of manual
2. Contact original installer or licensed professional.
A6 Ignition error 1. Ensure that the main gas supply valve is open.
2. Contact original installer or licensed professional.
A7 Abnormal operation: gas valve relay "open" 1. Turn off the main gas valve.
2. Contact original installer or licensed professional.
A8 Abnormal operation: flame detection 1. Turn off the main gas valve.
2. Contact original installer or licensed professional.
AA Overheating 1. Contact original installer or licensed professional.
AB Abnormal operation: heat exchanger temperature sensor 1. Contact original installer or licensed professional.
AC Abnormal operation: DHW temperature sensor 1. Contact original installer or licensed professional.
AD Clog of condensate trap 1. Contact original installer or licensed professional.
AE Blockage of flue Pipe 1. Clean the vent terminal.
2. Contact original installer or licensed professional.
E0 Abnormal operation: Outdoor temperature sensor 1. Check the outdoor temperature sensor wiring connection.
2. Contact original installer or licensed professional.
E1 Abnormal operation: Exhaust temperature sensor 1. Check the exhaust temperature sensor wiring connection.
2. Contact original installer or licensed professional.
E2 Abnormal operation: Exhaust temperature overheating 1. Contact original installer or licensed professional.
E3 Abnormal operation: Return water temperature sensor 1. Contact original installer or licensed professional.
E4 Abnormal operation: Pressure sensor 1. Contact original installer or licensed professional.
E7 Abnormal operation: gas valve relay "Close" 1. Contact original installer or licensed professional.
EB Overheating of DHW temperature sensor 1. Contact original installer or licensed professional.
EE Abnormal operation:Data Communication 1. Contact original installer or licensed professional.
EF Abnormal operation: eep-rom error 1. Contact original installer or licensed professional.
Table 9

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User Manual
Singular Combi Boiler - BTC 439003302 A (2021/03)

United States and Canada
Bosch Thermotechnology Corp.
65 Grove St.
Watertown, MA 02472
Tel: [phone]
Fax: [phone]
www.bosch-thermotechnology.us
BTC 439003302 A / 03.2021
Bosch Thermotechnology Corp. reserves the right
to make changes without notice due to continuing
engineering and technological advances.