Vaillant TurboMAX Plus 824E - Blowing fuse on PCB

[jimbob2468]

Hi All,

Just been browsing this forum seeing if I can get anything related to my boiler problem, have not found anything so asking if any of you can help or advise me...

My boiler failed on Thursday night at around 1AM, it was working perfectly at 8PM (approx) however when the heating turned off (from timer) it never came back on and hot water did not work either.

I went down and noticed the boiler was powered down and totally dead.

The next day I checked the mains and everything seemed OK, after some more research I found out there are two fuses on the PCB.

One fuse (1.5A on the right) was blown, so I replaced this with a spare on the cover however I fired the boiler back up and the boiler was on for approx 5 secs, then the fuse blew again...

upon power-on the boiler made a brrr brrrr brrr noise (best I can describe it...) then a click occured (similar to a relay/switch) and the boiler died...

I replaced the fuse and the same happend again...

I am at a loss what to do next.... Any tips or help would be very appreciated...

Just to let you know I have opened the silver screw on the pump and it seems to be rotating OK and it was also dribbling water OK.

I am otherwise looking to call out British Gas for a fixed price repair on Monday... (just wondering if its simple/diy) F.P. Repair is £205..

Thank you all for reading..

 

[glasgowgas]

somethings blowing fuse

could be fan, pump gas valve

anything inside the combustion chamber sadly we cannot advise on for gas safe critical reasons on a public forum

anything outside the combustion chamber can be checked if you have a multimeter and are familiar with resistance, voltage etc etc

 

[jimbob2468]

OK Understood,

Is it possible you can explain all items outside of the combustion chamber and how I would check the fan / pump...

I dont want to check Ianything gas / dangrous...

Is it possible a part has become frozen/seized due to the cold?

Thanks for the speedy reply..

 

[tdesnos]

hi mate,

It should be wired up by a fused spur and it should be a 3A fuse too. This fuse should be blowing before the ones on the PCB. In my experience, the ones on the circuit board only go when the fuse is too big in the spur. As for the cause of the fuse blowing; it culd be caused by a myriad of reasons. I'd be looking for a wire touching the casing or something like that. I'd be inclined to suspect the weather might be a cause too - but my imagination has fallen short as to what exactly! Sorry, just i'd try and help! No CH or HW isn't funny this time of year!

best of luck!

 

[glasgowgas]

3 pin RCD, 3 pin plug length of flex, assorted spades and terminals

wire in your test gear above to pump, run, does RCD trip

yes = faulty pump, no = pump ok etc etc

thats if the parts are powered 240 V

are they?

if you dont know, or dont know what the resistances should be or dont own a multimeter get a RGI in to fix, it will be quicker and safer for you in the long run

best of luck

 

[jimbob2468]

Hi

Thanks for the tips, I disconnected the pump and fired up the boiler, it blew a fuse again, so then disconnected the fan and the boiler seemed fine, and ran OK, ovbiously it wont fire without the fan being connected, so will get the fan replaced...

How does this sound?