Potterton Puma

[Paulmgf]

I have a Puma 80e which has had several problems over the 10 years we been using it(New fan, DHW switch, Modulation PCB dry joints, bleed valve etc.) I might be a bit paranoid but when the CH is running and the rads are hot, the boiler seems to be continually firing up and switching off approximately a couple minutes each time or even less. I am sure it never used to do this, I think there might be a problem with the CH temperature sensor. I've searched the archives but have not found any similar problems. Hope someone can help me.
PS. this my first post

 

[Gasguru]

Perhaps the boiler heating output just needs reducing. What size is your home? Small properties need the central heating adjusted down to the minimum setting (potentiometer on board...center near lower edge).

 

[Paulmgf]

Its a 2 bedroom bungalow, the control knob for CH is set at the 12 o'clock position and is normally in this position, i have tried turning it down but it does not seem to make any difference

 

[Paulmgf]

Thanks for your reply gasguru. I turned down the heating output using the pot but it made no difference, still cycling on and off. I checked the resistance of the CH Temp sensor this morning when the boiler was cold it read 11K and the DHW Temp sensor was read 14K should they both be the near enough the same as I think they are identical sensors.[/list]