Potterton Promax 15 HE boiler problem

[jdogg80]

Hi all,

I have a problem with my potterton promax 15 HE boiler.

I came home yesterday to find the heating was off, so I did what I normally do and hit the on/ off reset button on the front of the boiler but the boiler didnt start up, I repeated a couple of times but still nothing. I noticed the boiler was warm so I left it for half an hour to try again, still nothing. Last night I was in the kitchen and the boiler fired up on its own, ran for approximately 30 seconds and then switched itself off again. Having spent some time in the kitchen today I've timed the boiler starting up and switching off after 30 seconds at 10 minute intervals.

I would be very grateful if anyone cold shed some light on the problem.

I had the ignition PCB board replaced last month for another problem and everything had been working fine until now.

Cheers Jdogg80

 

[swbjackson]

What were/are the lights on the front of the boiler doing?

 

[jdogg80]

There are no lights on the front, just a metal outer casing with a reset switch

 

[swbjackson]

Sorry I was forgetting they're hidden on this model. To properly diagnose the fault an engineer needs to check the lights on the PCB which is behind the front casing.

 

[jdogg80]

I had both the ignition PCB and the control PCB out of the housing unit and still can't see any lights

 

[swbjackson]

There should be 3 lights on the front of the plastic housing.

 

[jdogg80]

There's no lights on the plastic housing just vents. I had it all opened up in the dark when the boiler kicked and there's nothing lighting up anywhere.

 

[swbjackson]

On the promaxes I've fitted and the instsructions show 3 lights below the reset button. There is also the screw for setting the boiler stat to the right of the reset.

 

[jdogg80]

I can assure you there are defo no lights on this model. The reset switch is on its own on a separate bracket.

With this info do you have any idea what might be wrong with my boiler?

Cheers

 

[gazthepottertonengineer]

He has an earlier version of the Promax ! Which does not have any lights and has 2 pcbs rather than the 1 Dc platform on the later ones!

Check to see that the pump is running!

 

[jdogg80]

Thanks for your advice.

for anyone looking in the future, my mate came round to have look, he checked the pump and it had power and was working. He took the front off the thermostat in the hall way and straight away the boiler started. He wasn't to sure what the problem was, dust, moisture or whether something had become displaced, but its still working so fingers crossed the thermostat doesn't need replacing .