Vokera Combi HE - fires but no central heating

[higart]

Started getting a fault on a Vokera HE combi - The Central heating will run smoothly 90% of the time but sometimes the boiler will fire and act as if all is well but no heat will get to the radiators. When acting normally, the fan kicks in but not when the heating fails. The hot water heats and runs fine at all times (with fan) and I have no error code on the system.

My question is this; is this likely to be a PCB fault, pump or some kind of valve problem? Sometimes when I turn the system off then on again, all kicks in fine straight away, sometimes not. Sometime ago we had Vokera send out an engineer who seemed content to replace everything until he fixed the fault! This time I thought I'd try and get a heads up before calling anyone out.

Thanks in advance for any input.

 

[Dotty]

You need a gsr in to look at your boiler. We cannot and will not give advice on the installation or repair of boilers for your own safety.

Please go to Gas Safe Register | Ensure your gas engineer is registered. or post a thread in the 'I'm looking for a plumber / gas engineer' section of these forums remembering to include your location. [DLMURL="http://www.ukplumbersforums.co.uk/im-looking-plumber-gas-engineer/"]I'm looking for a Plumber or Gas Engineer[/DLMURL]

If you are gsr please increase your post count to 10+ then send a pm to either Gas man or Redsaw who will then check you and then give you access to the gsr private forum.

Thank you.

http://www.ukplumbersforums.co.uk/central-heating-forum/42241-notice-gas-safety-related-advice.html