Fault Finding Solutions Sections I To M - Main Eco Compact System 15 Installation And Service Manual

10 Troubleshooting
Fig.61 Solutions sections I to M
I
CH system pressure less than
0.5 bar
J
Ensure that the boiler and
system are fully vented
K
Is there 230V at:
1.
PCB - X13 connector terminals between:-
Blue & Black (central heating mode)
Blue & Brown (domestic hot water mode)
see Wiring Diagram
2.
Diverter valve motor
L
Is mains water filter & assembly
clean, and rotor moving freely ?
Clean or replace
M
1.
Temperature sensors faulty.
Cold resistance approximately
10k Ω @ 25° C (CH sensor)
20k Ω @ 25° C (Flue sensor)
(resistance reduces with increase in temp.)
2.
If pump is running the heat exchanger
could be obstructed
60
YES
NO
Check wiring and PCB - X22
connector for approx. 5V DC
between green & black - see
Wiring Diagram
NO
YES
Check flow temperature sensor connections
and position.
Cold resistance approximately
10k Ω @ 25° C (CH sensors)
(resistance reduces with increase in temp.)
YES
YES
Check diverter valve cable
YES
YES
NO
10.2.4

Fault finding solutions sections I to M

Restore system pressure
YES
Replace hydraulic pressure switch
NO
Replace PCB
System fault - correct
NO
Go to section 'B'
NO
Replace PCB
Replace motor
Check wiring and PCB - X22
connector for approx. 5V DC
between red & blue from Hall
Effect sensor -
see Wiring Diagram
NO
Replace PCB
NO
Replace sensor
YES
Replace heat exchanger
Replace sensor
YES
Replace Hall Effect Sensor
PN-0000319