potterton profile 80e keeps blowing fuses

[riseandshine]

Hi my potterton profile 80 is quite unreliable, the PCB and air switch were replaced 18 months ago, and now it has stopped working again.

The pump and fan are working but there is no ignition.... and the worrying thing is that the 1amp fuse on the pcb blew 3 times and the 3amp fuse in the main switch blew once.

Has the air switch or pcb gone again, if it has what is making them fail?

Is it time to cut my loses and replace the boiler?

Thanks for your help in advance

 

[Agile]

If correctly connected the boiler should power the pump.

The fault is most likely to be the pump.

Its easy to check that by powering the pump seperately from a socket with a 3A fuse in the plug.

See if the boiler is fine and if the pump fuse blows.

Tony

 

[riseandshine]

I may have sowed some confusion....

The fuses (at the moment) are ok, the pump appears to be running and the fan is running, but there is no ignition spark.

Sorry for the confusion

 

[Agile]

I dont know how anyone could conclude there is no spark from that description.

Regardess if fuses have been blowing my expectation is likely to be correct.

If the boiler is not sparking then all you can safely do is ensure the ignition lead is in place where it clips into the rear left of the PCB.

If thats there you will need a gas engineer to identify the exact fault as safety and gas tests are required.

Tony

 

[twgas]

Have you proved the fan and pump are working, and if so, how?

 

[riseandshine]

I changed the fuses and the pump and fan started humming. The fuses haven't blown yet.

I would like to understand what is going on with this boiler before calling an engineer again because I did pay a lot to get the pcb and air pressure switch changed only 18 months ago.

 

[riseandshine]

I did get a corgi eng to look at it but he couldn't figure out what the problem was, he said he need the full manual.

 

[riseandshine]

ignition lead is crimped to the rear left of pcb as you stated. Previously a corgi eng put some gaffer tap on the chasis he said to revent it sparking to the wrong place. (I am on my 3rd corgi eng trying to fix the boiler.)

 

[twgas]

I changed the fuses and the pump and fan started humming. The fuses haven't blown yet.

I would like to understand what is going on with this boiler before calling an engineer again because I did pay a lot to get the pcb and air pressure switch changed only 18 months ago.

This is not proof of working, motors often make a working type noise when they have seized.

 

[riseandshine]

Hello again,

I changed the fuses and the pump and fan were working (I know the pump was working because when I close the gate valve I could hear the water in the pipes).
So I thought it was the air pressure switch, so I changed that and amazingly the boiler ignited. The a couple of minutes later the fuse on the pcb blew again. so I replaced it and it blew immediately....

Does anyone have any ideas please? Do I have a short circuit somewhere or is the pcb faulty? any guesses?

Thanks
Charles

 

[Boilerman2]

Get a BOILER Engineer in who understands the ELECTRICAL SIDE of the boiler, this is a basic boiler and someone with a modicum of knowledge and a MULTIMETER should be able to figure it out, or hang his head in shame!!

 

[Agile]

Charles, why not say where you are in the country as we may have a forum member near you.

For example we have one called "NOGOODATFAULTFINDING" who could be just up your street?

Tony

 

[riseandshine]

Cheers Tony..... I think?

I live in Bristol

 

[herebriefly]

Charles, why not say where you are in the country as we may have a forum member near you.

For example we have one called "NOGOODATFAULTFINDING" who could be just up your street?

Tony

Not really the attitude to take is it Tony?

Pump, fan or leak into a MVlv. Its such a simple boiler, that even my 15 year old could fix this. Has the pump been put on a flying lead yet?

 

[riseandshine]

haven't done the flying lead...

but have managed to trace a possible short circuit, one of the wires to the fan had a cut in its insulation, looks like wire had become squashed between the fan and the frame when it was installed.

have taped the wire and boiler is working (sort of, well at least fuses have stopped blowing).

The boiler is cycling on and off every few minutes - pump runs constantly, fan, gas and ignition are cycling on/off
Also the programmer doesn't have any affect of the running of the boiler, even if the programmer is set to off for HW and CH, the pump still runs and the boiler continues cycling on/off.

Think I'll change the PCB again.