Baxi 124 Combi - Fault Finding Solutions Sections F-H

50
17.0 Fault Finding
© Baxi Heating UK Ltd 2017
Replace PCB
Check and correct if necessary
1. Ignition electrode and lead
2. Electrode connection
3. Spark gap and position
Check wiring - see Diagram
YES
NO
F
5
±
1
4
±
0.5
1
0
±
1
Spark Ignition
Electrode
Flame
Sensing
Electrode
Electrode Position
Viewing Window
Burner
Check and correct if necessary
1. The set of the gas valve
(CO
2
values - see instruction)
2. Flame sensing electrode and lead connections
3. Flame sensing electrode position
1.
2.
G
Replace sensing electrode or PCB
Replace PCB
YES
Replace safety thermostat
YES
NO
Safety Thermostat operated or
faulty
Check for and correct any
system faults
H
Allow to cool. Continuity
across thermostat terminals
more than 1.5 ohm
NO
Check Flow & Return Sensors -
see section ‘D’
NO
Is 110 still flashing ?
YES
Check supply pressure at the
gas valve:-
Natural Gas - Minimum 17 mbar
Propane - Minimum 37 mbar