PottertonKingfisher boiler pilot keep going off

[P4uLuv]

Hi,

I am having a problem with my boiler. When i put the pilot on, it works fine but when the central heating or hot water comes on, there were some small explosion and I could smell burning but an engineer clean it up and also clean the gas valve. It worked fine for about a week but then suddenly the pilot keeps going out regularly, I would say every hour..Do you think it is the gas valve, considering i changed the thermocouple a week ago..or is the boiler heating up? somebody suggested to change the thermostat? is that right?

your help will be much appreciated..
parvez

 

[namsag]

More info, is it going out when just pilot on or with main burner on

 

[P4uLuv]

when burner is on.

 

[namsag]

My first thoughts would be partially blocked pilot and being pulled away from the t/couple when the main burner is on , you maybe able to see this, have a look through sight glass as main burner comes on . Does the pilot get smaller or lazy yellow flame. You may not always notice it

 

[P4uLuv]

Thx for your reply. You are right there is a lazy yellow flame..however, i would say the flame get smaller but when the burner is on, the yellow flame is a bit fierce before shutting down..

 

[namsag]

Get guy back out to clean boiler properly, original kingfishers had a shaling problem with the heatexchanger and need a thorough clean

 

[P4uLuv]

He came in today and it clean it again..it seems to be working at the moment. many thx for your reply..

 

[DP]

What Namsag is suggesting is to service the boiler. I don't think Namsag was suggesting it (whatever it is) be done again.

He came in today and it clean it again..i

Boiler service (my method) is to sweep the main heat exchanger (after removing the top inspection hatch and burner assembly), clear out combustion chamber, clean burner and injector, clean pilot assembly and burner, check gas rate and if boiler is OF check flue and in all cases check compartment ventilation is fitted therein. Seals and other perishable should also be attended to. Flames should all be blue.

also clean the gas valve

Don't understand. How do you clean the gas valve?

 

[P4uLuv]

Thx DP, the gas valve has been cleaned. Since this morning, all seem ok with it..burner not going off and both HW and CH are fine..many thx for your reply...