Potterton Prima F 60F issue

[nepur]

I have had a problem with my Potterton Prima F 60F for a while now. The boiler seemed to stay on for 5 minutes and then shut down for 10 minutes, almost as if it was cooling down and would then kick in and the cycle is repeating.

I have changed the air pressure switch and the PCB, and it doesn't seem to have made a difference. I did have plastering done in the house when a couple of the radiators were removed, but have now put them back.

While the boiler is on, the radiators start getting hot, however, as the boiler shuts down in a few minutes, the radiators start cooling again. The pump is running all the time the heating switch on the timer is on. So even when the boiler shuts down the pump is still running. I guess this is why the radiators cool down quickly as there is no hot water being pumped through???

I do not know what else could be the problem. Even while the boiler is on for those few minutes, it doesn't stay on all the time. It kicks in and i can see the flames, but then the flames start to flicker and it shuts down for a few seconds and then kicks in again and the cycle is repeated, until it shuts down for ten minutes or so. Then the whole cycle starts again.

i apologize for the long explanation, but thought the more I describe the problem, the easier it might be to understand and hopefully resolve.

Any help/suggestion would be much appreciated.

Thanks

 

[baxpoti]

It kicks in and i can see the flames, but then the flames start to flicker and it shuts down for a few seconds and then kicks in again

What do you mean by flicker, are the flames lifting off the burner?

 

[nickso]

possible flue corrosion

 

[nepur]

Hi baxpoti,

The flames start but then go on and off like those magic candles once you blow them and they come back alight, but a bit faster.

hope this helps.

 

[baxpoti]

For starters
Clean the pilot assy

 

[nepur]

thanks baxpoti,

I will attempt to clean the pilot assembly (I assume that's what you were referring with "assy").
thanks

 

[gavinda]

possible flue corrosion

check the flue terminal theres usually a little hole about 3/4 inches in on the inner flue. simple enough job to do as long as the 4 terminal screws arent cemented over. have a listen too to the fan and make sure thats not cutting out. if so it may be the restrictor on the aps.. little brass injector gets crapped up.