Vokera Excell 80 SP Problems

Hi I moved into a flat about 2 months ago with the above boiler and it has just started causing me a few problems. The other night the boiler started firing (as if demand for hot water) and kept doing so every 30 seconds. Also if any of the hot taps are used all the radiators seem to get hot suppose this could just be some kind of heat dump though. Had a play around with the controls on the radiators and the water/ch temperature control on the boiler and seems to have stopped the random firing.

Also noticed a funny noise sometimes when the boiler is cutting out. Strange to describe but almost like a short circuiting noise.

Fan seems to be running ok. That's about as far as my knowledge can get me with describing the problem any ideas would be appreciated.

Cheers

Jon

Forgot to add that from information previous owner left it was serviced in Feburary and all was fine except venturi cleaned and DHW diaphragm changed

the heat dump will occur after a hot tap is shut off. so test from cold and feel the htg pipe as soon as it fires for a hot tap.
if its instantly getting hot then it will probably a problem with your diverter valve.

the random firing is either frost protection or hw flow switch sticking

What activates the frost protection?

Crux of the problem is the service that was carried out.

Looks like diaphragm might have been perforated, so that was replaced. Venturi can clog up on any boiler- that was also cleaned.

But above does amount to a servoce as dictated by the manual. It is lack of proper service that is now giving you the sore head.

I am in Beasden and can offer to carry out repairs to your boiler.

Good boiler, so do not entertain anyone who tries to sell you a new boiler.

Sounds good. I'm in Mount Florida. Would that be ok? If I could get your contact details and arrange something for a couple of weeks it would be good.

Cheers

I cannot post (forum rules) my details but if you look at my forum profile, you will get it there.