Glow worm Comact 100e problem

[gq52]

Boiler now about 5 yr old.

Hot water system works Ok on its own.

Since starting to use CH, it fires and runs OK for about 45 minutes before cuts out and the lockout Led lights. If left for about 90 mins, c/h will operate again. Hot water only will operate again straight away.

Radiators seem to be getting too hot.

Does this sound like the C/H thermistor is faulty?

Also was getting quite a bit of pcb relay clicking - this has stopped since moving the thermistor slightly.

 

[Gasguru]

I seem to remember having a similar fault and it did turn out to be the flow thermistor.

 

[pannierstan]

Could be the microswitch on the flow switch. Had many go wrong and its now been modified.

Stan

 

[gq52]

Could be the microswitch on the flow switch. Had many go wrong and its now been modified.

Stan

Thanks Stan but ...

There are 3 microswitches - 'Low water pressure', 'pressure differential' and 'domestic hot water' .............which one do you mean?

Ive had problems with the diff pressure one before and replaced the diapgram last winter, but not the microswitch itself.