Potterton puma 80 bolier no hot water but constant heating

[Monique]

Please help me. My combi boiler is 7 yrs old. I have lived here for 2yrs with no previous problems however I have never had it serviced.

Past 3 months my central heating has been coming on when I have run the water for a bit. This is despite the timer being on off, the CH button on the boiler being on off and the CH temp on minus on the boiler. I have kept the thermostat on 15 degrees. To temporarily solve this I turned all the radiators down using their individual little knobs.
BUT now for the past 3 weeks my pilot light keeps turning off. I have to re-light it every time I need hot water. The length of time I then get hot water has been reducing; it is now down to about 3 minutes.
When I turn the hot tap on the boiler makes all the necc noises but there is no flame. The noises continue until I just turn the boiler on standby.
A friend replaced the Therma Coppler (not sure if right spelling) this however hasn’t helped.
Now what? Do I need to replace the valve or pump? Is the boiler over heating? Do I need to get in the experts? I would be ever so grateful for any suggestions.

 

[ChrisR]

Standard problem on your boiler - we get asked about once a week! The tap water flow switch is sticking on. The part which usually fails would be about £45 + fitting.

 

[Agile]

Chris finds that its the switch itself but in my area I find thats its more often caused by the operating pin being stiff rather than the switch itself.

Tony

 

[ChrisR]

No Tony, you're misreading, again! As I have pointed out before, the part with the sticking operating pin is called a flow switch. The electrical microswitch, which occasionally gets water in or causes problems, is about £10 not £45.

 

[Monique]

Thanks guys, someone is coming around to look at the boiler tonight and i will show them your posts so they know what to look at. I'm confident that it will work now.

 

[Agile]

It would be much better to get someone to see your boiler who has the skill to diagnose faults by himself!

Tony

 

[kier]

so if its not been serviced/safety checked in last 2 years you have saved approx £120.00
so the money you have saved by not having it serviced can now be used to repair it.
get some one who fully understands pumas as they often have a sharp bite as many bits can go wrong.but easily repaired.
good luck.