PCB/Gas valve

[Dave543212345]

We have had our boiler repaired. The gas valve was not working as there was no power to it, so the PCB was replaced, and immediately fried by the gas valve.
So we needed the gas valve replaced and then a 2nd PCB. To quote the workman, "What we could have not foreseen at all is that the reason the PCB had failed was because the gas valve was causing it to short circuit. There is no way to tell that this would have been the reason for this failure. Only after installing the new PCB were we able to determine that the gas valve was blowing the board."
Does this sound reasonable? Obviously it leaves us with the cost of 2 PCBs (about £300 + vat each) or is it something that could have been foreseen/checked for before putting a new PCB in?

 

[bernardgreen]

There is no way to tell that this would have been the reason for this failure.

There is a way, the technician could have checked the gas valve and wiring to it for short circuits before installing a new PCB.

Unfortunately the manufacturer's fault finding information seldom includes anything about testing individual items to determine which item is at fault.

 

[picasso]

What boiler do you have ? £300 + vat seems a bit excessive.

 

[Dan Robinson]

Suprima

 

[Gasguru]

That's lack of experience by the repairer...some boiler gas valve failures are well known to take out the pcb...the Suprima being one of them.
It's common to feed gas valves with raw DC and when the a gas valve solenoid fails it can destroy the components on the pcb that convert AC to raw DC.
The gas valve solenoids should have been checked before pcb replacement.

A quality recon pcb from CET LTD would be under a £100.

The rectifiers/surge suppressor components are either on the main pcb or in the gas valve lead connector or very occasionally within the gas valve...and they are often vulnerable.

 

[mattylad]

When I come accross a burnt out PCB I always try to figure out how/why it got burnt out in the first place.
Test the things that are being plugged into it before connecting them into the pcb.

The cost of the 2nd board IMO should be his, it was his failure to test the gas valve not yours.
Get haggling.

If you have to pay £600 just for 2 of the parts, your nearly at the cost of a new boiler if not over for the whole job.

 

[gas112]

vailant turbomax by any chance ?

 

[bernardgreen]

The rectifiers/surge suppressor components... ~~~ and they are often vulnerable

And yet they do not have adequate protection due to cost cutting by the manufacturer of the PCB and/or the manufacturer of the boiler.

A simple and low cost PolyFuse on the PCB in series with the gas valve supply would protect the PCB from damage.
Example https://uk.rs-online.com/web/p/resettable-wire-ended-fuses/5176685/

edit changed link

 

[ianmcd]

And yet they do not have adequate protection due to cost cutting by the manufacturer of the PCB and/or the manufacturer of the boiler.

A simple and low cost PolyFuse on the PCB in series with the gas valve supply would protect the PCB from damage. Example [url="https://uk.rs-online.com/web/p/resettable-wire-ended-fuses/6571772/2] HERE [/url]

 

[ianmcd]

Benny , you say that you are a man that doesnt want for means, why do you not start up a company and go and do all these repairs or upgrades that you presume that you are an expert in ??? I know because you havent a feckin clue

 

[Dan Robinson]

Because he enjoys whining to mods on here too much. Old fart has me locked out of the the garage thread .

 

[ianmcd]

Because he enjoys whining to mods on here too much. Old fart has me locked out of the the garage thread .

its a feckin garage, one bedroom one bathroom but bennyboy thinks its a hotel

 

[bernardgreen]

why do you not start up a company and go and do all these repairs

As a sole trader I did repair PCBs used in a gas heater, The manufacturers had ceased supporting the heaters leaving a heating company unable to repair their client's heaters.

 

[ianmcd]

As a sole trader I did repair PCBs used in a gas heater, The manufacturers had ceased supporting the heaters leaving a heating company unable to repair their client's heaters.

Benny stick to plumbing and drainage posts because your posts are absolute shoite

 

[Dave543212345]

thanks for all the replies. At the moment, I'm waiting for them to tell me the part numbers that they used.