Failure / Error Codes Overview - Buderus Logamax plus Service Manual

3 Failures / Errors
3.2

Failure / Error Codes Overview

Failure
Code on
Display Failure Descripton
MAP not selected (Fan speed adjustment
according the flue pipe length).
Combustion chamber NTC failure (behind
1H
burner) : - when the temperature by CC NTC
reached to limit or
- when NTC not detected or open circuit
Gradient limit : Temperature rises too rapidly
2P
in heating mode.
Fan sensor not detected.
3A
Fan speed can not reached to target speed.
3C
Overheat lock-out by temperatur limiters
4C
(STBs) (Flue gas + prim. Heatexchanger). In
this case ; Heat demands is blocked and
pump stops 3 min. later.
Flow temperature sensor failure (pump is run-
4Y
ning).
Ignition lock-out (flame not detected) (pump is
6A
running).
Safety valve leaks.
6C
Short circuit / failure in water level switch.
B3
Domestic hot water temperature sensor not
CL
correct installed or failure.
Modulator coil failure (regulator valve on gas
d7
valve)
Tab. 4 Failure codes
8
Steps
Check the adjustment /selection via service func-
tion 2.b.d).
Check the and the heat exchanger surface,
whether is blocked or not. And check the sensor
and the connections.
Check the pump, system pressure and by-pass
circuit.
Check the fan.
Check the fan for the blockage and the electrical
supply.
Check the system presseure, temperature sensor,
pump and fuses on board. Discharge the air in
system. Check also the flue gas pipe and heatex-
changer.
Check the flow temperature sensor and the con-
nection.
Check the gas cock, gas pressure, electrode and
the cable connection.
Check the gas valve, the cable connection and
electrode set.
Check the condensate water drain and recuperator
(condens-heatexchanger).
Check the sensor and cable connection.
Check the cable connection.
GB012 - 25K