Faults - Bosch Therm 4000 S Installation And Operating Instructions Manual

9

Faults

Installation, repairs and maintenance must only be carried out
by approved contractors. The solutions for problems that may
arise are described in the following table.
Display Description
A0 Damage to the temperature sensor in the water inlet/
outlet.
A1 Significantly increased temperature in the casing
(external temperature too high, limescale in the
internal body of the device).
A4 Defective air temperature sensor in the casing.
A7 Defective hot water temperature sensor.
A9 Hot water temperature sensor incorrectly installed.
Low gas supply pressure.
C7 Fan not running.
SC Water flow rate exceeds the maximum limit.
SC Flue gas connection obstructed.
C1 Air volume not sufficient for operation.
E0 Fault in the electronic block.
E1 The hot water temperature sensor notifies
overheating.
E2 Cold water temperature sensor defective.
E4 The air temperature sensor notifies overheating
(escape of combustion products in the combustion
chamber).
E9 Thermal fuse.
EA No flame is detected.
Table 18
Therm 4000 S – 6 720 815 298 (2017/05)
Remedy
▶ Check the temperature sensor and relevant
1)
connections.
▶ Call an approved contractor.
The device regulates the output automatically to
prevent overheating.
▶ Check the temperature sensor and relevant
1)
connections.
▶ Check the temperature sensor and relevant
1)
connections.
▶ Check the installation.
▶ Check the gas supply pressure.
▶ Check the fan connections.
▶ Close the hot water tap and then open it again.
▶ Check the water filter / flow limiter
▶ Remove dirt or other obstructions from the
suction pipe or flue.
▶ Press the reset button.
If the problem persists:
▶ Call an approved contractor.
▶ Press the Reset button.
If the problem persists:
▶ Call an approved contractor.
▶ Let the device cool down and try once more.
If the problem persists:
▶ Call an approved contractor.
▶ Check the temperature sensor and associated
1)
connections.
▶ Switch off the device.
▶ Call an approved contractor.
▶ Call an approved contractor.
▶ Check the gas supply pressure, power supply,
ignition electrode and ionising electrode.
▶ Press the Reset button.
Faults
1)
1)
27