PCB Disaster on Potterton Suprima 40L

16 Jan 2012
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West Midlands
United Kingdom
Hi there, after help.

We recently noticed a problem on our Potterton Suprima 40L boiler, was not firing at all.
Called an engineer who explained the problem was a faultly PCB which is very common on these boilers. No problem, new PCB ordered (albeit a new design) and the engineer fitted it.
Boiler worked fine for a few hours then again nothing, and the Greenish/Orange light is stuck on and the boiler again will not fire.

The engineer has checked a few things out like Fan etc, all working okay but he still cannot get the thing working.

Any ideas would be gratefully accepted
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i have had to replace the board on one of these twice in two years. they are a problem. however, has the last guy done a full fault finding process on it?

the diode indicates certain faults depending on its actions, has he had the manual to go through it all? it might be a different fault and is purely coincidental, however there might be a faulty part somewhere else in the boiler/system that is taking out the board.
Its alway possible that he changed the PCB without properly checking all the other components.

The new PCB gives a significant range of fault codes!

no water leaking inside the boiler?

once spoke to somebody who had their PCB replaced on a different boiler.. but the plumber never fixed the leak coming from the pipework above the pcb inside... what happened was after a while the leaking water got at the pcb and killed a perfectly working board.
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Thanks for the resonses.

Boiler kicked in and worked this morning off the timer for about 45mins and then shut down again. Very bizarre !!

No water getting into boiler and he did check the Fan etc, all working fine

Getting hot water fine as well !
If the boiler works for hot water and not heating then it's not a boiler fault it's external controls.
I would be checking zone valves.
This is the reason most change thermistor/OH and board at the same time ;) , water/heating will work fine until the OH cuts in and locks out. :D

Although these boilers suffered with the dreaded board problem many were mis-diagnosed as board fault. :rolleyes:

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