Glow worm Mircron 60FF Boiler strange workings

[kjc1957]

Hi ~ need some advice or direction. My 5 year old Glow worm Mircron 60 FF boiler is playing up.

When the CH is on and the room thermostat is up to max the water is being pumped around the system, but the boiler is not firing up.

When the HW is on the boiler keeps firing up in approx the same sequence 20 secs on 10 sec off.

When both CH & HW on as per HW only

Ideas, replaced PCB board 12 months ago because it had burnt out, and had a new one fitted yesterday as we had similar problems to when the first one died.

 

[Agile]

I am left wondering who replaced this PCB yesterday and why it was replaced without diagnosing the fault first?

Tony

 

[kjc1957]

Tony,
I did, because the boiler was continually firing up, and the other problems where not observed at the time.

This seem the easiest option at the time. However looking back your are right maybe it was not the board.

However, disappearing today for work and leaving the wife with a cold house & no hot water for a few days this seemed the quickest choice.

Now left wondering how long these faults where in the system. Also should I get a plumber or a heating engineer to examine the system.

Thanks

 

[Agile]

I would always advise a heating engineer although many plumbers are well able to deal with your problem.

As far as I can assess your boiler is probably fine and the problem will be associated with the pump and motor valves or just possibily a blockage or lack of water in the system.

I dont think it is fair to leave wife and kids for several days during the winter without hot water and heating. However if you have an immersion for HW then the weather is actually pretty mild when you read a thermometer.

Tony

 

[corgigazza]

if nothing ealse works as above recommend replacing thermistor (as pcb all ready replaced) had similar fault before.