vaillant turbomax plus 828E power supply problems

Hi All,

I'm new to this forum and was searching for an answer to my problem, didn't find one and decided to join so I could ask for advice - apologies in advance as I know I sound like a leech!
I am not in the gas trade or qualified in any related discipline, so this problem is for my own boiler in my own property, I am not using your brains for any profit or taking risks by working like a cowboy on somebody else's boiler.

Right, with all of that out of the way, my problem appears to be relatively simple on the face of it:
All of a sudden at lunchtime yesterday, my wife switched the hot water on and all of the power in the house went off! After this happened a couple of times, it was obvious that the boiler was the culprit - the electricity supply stays on when the boiler is off - when the boiler is switched on again, the main switch on the house circuit board trips and that's that! Because there's no power, there are no fault codes visible on the boiler's display so I can't help you there.
The only other advice I have had is from a friend (who is a plumber NOT a gas fitter!) who has not looked at it who said it might be the motherboard in the boiler - is this possible? As I said there is no power to the boiler so I'm sorry I can't give more info, should I be on the electrician's forum? If it is the motherboard, is this a pro's job? I could change one on a PC but appreciate it's probably not that simple!!
Please help if possible. All help will be appreciated and taken seriously - if somebody says leave it to a pro then that's what I will do, but an idea of the cost of getting a qualified engineer to do the job would be greatly appreciated as I'd rather not be ripped off!!

Thanks in advance
Steve

edit didnt read header

i`ll get ma coat

You can safely ignore the advice from somebody who tells you it is the motherboard; boilers don't have one.
He probably means the pcb, and that wouldn't be my first guess either.
It could be a number of things, pump and fan would be the most likely culprits.
What you need is a RGI who is good at faultfinding.

bengasman said:

You can safely ignore the advice from somebody who tells you it is the motherboard; boilers don't have one.
He probably means the pcb, and that wouldn't be my first guess either.
It could be a number of things, pump and fan would be the most likely culprits.
What you need is a RGI who is good at faultfinding.

Click to expand...

In this case, correct, in general, wrong

the Vaillant 242E and EH have motherboards, the Lynx Mk1 has a motherboard, I could go on

OP - the two most likely sources of your problem are the pump and the fan, this vaillant boiler has IIRC an EBM fan which has very poor quality windings and can go short circuit

raden said:

bengasman said:

You can safely ignore the advice from somebody who tells you it is the motherboard; boilers don't have one.
He probably means the pcb, and that wouldn't be my first guess either.
It could be a number of things, pump and fan would be the most likely culprits.
What you need is a RGI who is good at faultfinding.

Click to expand...

In this case, correct, in general, wrong

Click to expand...

You are missing my point. Anyone calling a pcb a motherboard is clearly not a RGI, or somebody else with advanced knowledge of boilers. They are likely to give the wrong advice, as is demonstrated in this thread; it is unlikely that the "motherboard" is the culprit.

ben a 242e has a motherboard at the back of the control box the 5 of so pcbs plug into it

I know what you mean, it's just that I have never heard them referred to as "motherboard"; main board, main pcb, sequence board maybe ever, but never motherboard.

Put it this way, I have never tried it, but I reckon I would get a few laughs if I asked my supplier if he had "a motherboard for a 242e"
"oi mate, you should try pc world"
"hey geez, you want some hard drives with that?"

Not that it matters a lot, if you don't have the part number, you're bound to get the wrong one anyway, so that is what I normally give them.

if its doing the main fuse my money is on the pump unplug the pump and try again,

Back to the boiler!

Its easy to disconnect the pump and repower and 90% of the time that will be where the fault will lie!

You, with a little skills, or a professional can replace the pump.

There is someone who posts on this forum in L-P called "Sooey". You should get his details in his profile to contact by clicking on his name if you want a friendly professional in your area.

Tony