Boiler not runs stops then won't fire up again.

[mickcottam]

I have a Baxi Solo 3 PF50. The boiler will start, run for a while and then stop after approx 10-15 minutes. It wont start again for a good period of time and then repeat. It isn't stopping because the thermostat has reahced the temperature. I increase the thermostat temp to try to get the boiler to run again but nothing. The timer controls etc are on too. When it stops the only light left on is the boiler on light. I have changed the thermostat just in case this was faulty. I've looked at the fan and it runs and spins very freely. I've looked at the PCB and there is some browning to one area of it. I'm thinking this may be my problem, but i don't want to spend on a new PCB if that isn't it.

Any thoughts or guidance would be gratefully received.

 

[twgas]

does any heat get away from the boiler - to the HW tank or radiators?
pump is a likely candidate for your problem.

 

[mickcottam]

Yes radiators get hot, so does water in cylinder.

 

[twgas]

if the rads and water are hot why do you think the boiler should be firing?

 

[mickcottam]

Because is set my thermostat to 22/23 and the boiler stops before getting there. It stops at around 20 about 10 mins of being on

 

[twgas]

if your system is up to temp the boiler will shut down, if the room temp is too low it suggests the rads are too small or they have a build up of sludge, reducing the output.
as the return water cools a bit the boiler will refire, there does not appear tobe a problem with your boiler. but the system.