boilers

[roaring51]

Just replaced the PCB on a potterton combi 80. It fired up and ran perfectly for 3 hours but has now gone back to not firing. The original PCB was the type with resistors etc and the new one is the one with the micro processor. Does anyone have any ideas or knows of the new ones being unreliable. Thanks

 

[Red_Man]

When you say its not firing up....

Are you getting anything at the boiler at all?

 

[Agile]

Why did you replace the PCB?

What were the symptoms?

Is this your own boiler?

If not are you registered?

Tony

 

[Red_Man]

Don't worry if you're not Gas registered.

You don't need to be for changing a PCB

 

[roaring51]

Hi Red_man. Thanks for getting back I'm getting power to it, I've pushed the pressure up to about 1.5 bar and held the rest button down for 10 seconds as it says' in the fault finding guide but still no fire up when I run the hot tap or turn the thermostat up.

 

[roaring51]

No I'm not gas registered, but I'm a fully qualified vehcle electrician, have worked on air conditioning systems and had 20 years of experiance in the building trade including a lot of plumbing and electrics and never had a disarster. I replace the PCB because it had wopping great burn mark in the top left hand corner and was arc-ing when I touched the wiring attached to it.

 

[Red_Man]

If the same has happened again, It's likely a faulty component is causing the PCB to blow, the same faulty component is now giving you problems.

 

[roaring51]

Thanks Red_Man. I'm not at the property at the moment. But I 'll check it in the morning, to see if it's burn this one out, I hope not as the bloody thing cost me £180. any ideas which component It's likely to be or what process of elimination I can try to find out

 

[Red_Man]

£180 is a lot of money for an 80 PCB

You'll wanna hope it hasn't blown something on it now! You wont get your money back.

Could be anything really, Fan, Pump.

What's happening when you run a tap... does the Fan start? Can you hear clicking as if it's trying to ignite?

 

[roaring51]

Tell me about it ! It's amazing what you'll pay when your desperate. The fan starts up when I run the hot tap and seems to run freely enough.

 

[roaring51]

ps but there's no clicking from the ignitor

 

[lawrance]

Hi Red_man. Thanks for getting back I'm getting power to it, I've pushed the pressure up to about 1.5 bar and held the rest button down for 10 seconds as it says' in the fault finding guide but still no fire up when I run the hot tap or turn the thermostat up.

This is quality! you obviously do not have a clue how to fix a simple boiler or work safely on it

 

[MIGEM]

Don't worry if you're not Gas registered.

You don't need to be for changing a PCB

If it is the modulation control board, you need to reset / check the heating range.
Are there not 3 boards on an 80?

 

[roaring51]

Hi Red_man. Thanks for getting back I'm getting power to it, I've pushed the pressure up to about 1.5 bar and held the rest button down for 10 seconds as it says' in the fault finding guide but still no fire up when I run the hot tap or turn the thermostat up.

This is quality! you obviously do not have a clue how to fix a simple boiler or work safely on it

I've got a cousin called Lawrence. No one can stand him either. Thanks for your input, but I'm a bit busy getting back to people that are genuinely trying to help. So s.o.r.r.y l.a.w.r.e.n.c.e got to go, because if all else fails, then yes I'll have to get a boiler engineer in preferably one, with a slightly more interesting name and persona than your good self. Best of luck in life being called Lawrence, Lawrence.

 

[DP]

PCB is one component that (I am sure) makes a fortune for the suppliers. It is not because these items are unreliable but because the people (more often than not) are prone to replacing it based on suspicion alone. It looks like OP is fallen into that trap as well despite the fact that he claims to be “”fully qualified vehcle electrician, have worked on air conditioning systems and had 20 years of experiance in the building trade including a lot of plumbing and electrics and never had a disarster. I replace the PCB because it had wopping great burn mark in the top left hand corner and was arc-ing when I touched the wiring attached to it.””

I must say, being a fully qualified vehicle engineer, knowledge of air conditioning systems and many years of field work on a building site means squat as does being a RGI. What one needs is basic fault finding skill and an investigative mind which often, not always, culminates in success. A wopping great burn mark is NOT a sign to replace the PCB, more a case of bad solder joint which would have been fixed if you had drawn on your multiskill experience.

Why not dig out your multimeter and fault find with aid of boiler manual? Instructions are quite good. I see no reason why you would not be able to come to a solid conclusion why the boiler is not working (provided the boiler is your own and not someone else’s).

When someone says you do not need to be registered gas installer to replace the PCB, I would suggest that person get in touch with Gas Safe for verification. PCB is integral part of gas combustion so non ‘gas person’ should resist the temptation to tinker with anything within the boiler.

Some of the advise being given is based on loose assumptions. If the boiler belongs to someone else, walk away and let the repair be carried out by registered installer. Will you be able to sleep at night if the repair you carried out caused the boiler to blow up or caused it to release dangerous fumes leading to fatalities? Are you even insured to carry out such work?