Control Board; Condensate Trap Assembly; Air Pressure Switch - Bosch Singular 4000 Service Manual

Service Manual

7.17 Control Board

Part No.
Function
Failure Event
Effects
Error Code
Diagnostic
Color/Number of Wires
Table 20

7.18 Condensate Trap Assembly

Part No.
Function
Failure Event
Effects
Error Code
Diagnostic
Color/Number of Wires
Table 21

7.19 Air Pressure Switch

Part No.
Function
Failure Event
Effects
Error Code
Diagnostic
Color/Number of Wires
Table 22
1 8 |
7738007249 (Singular 5200)
7738007248 (Singular 4000)
To control each component and performance of unit.
 Malfunction of control board.
 Unit does not operate.
 A component does not operate within the unit.
 In case of the control board failure, the water heater does not
operate.
—
Visual inspection: Connection or breakage of water or burn marks on the
control board.
N/A
7738007273
Drain condensation, which is created while combusting.
 Fail to drain condensation caused by clogged trap.
 Condensation leakage into the unit.
 Stop combustion.
 Condensation leakage.
AD
 Visual inspection: Connection or breakage of wires, check for
physical damage to the trap body.
 Voltage Check: Check range of voltage shown below.
Green-Red: AC 24 V
7738007247 (Singular 5200)
7738007246 (Singular 4000)
Prevents operation of the unit due to unsafe condition. Back pressure or
blockage has occurred in the exhaust vent.
No operation of the unit.
 Stop combustion.
 No operation of the unit.
AE
 Visual inspection: Connection or breakage of wires.
 Voltage check: Check range of voltage shown below.
Green-Green: DC 5 V
Singular Combi Boiler - BTC 439002301 A (12.2021)