ferolli 77ff boiler fault

[Jimmyjaffa]

Hi yes that worked, when i switched back on the fan did not cut in like you said, but now ive lost my live feed to the gas valve again, but when i switched the main control nob to the ch on postion the fan clicked in out about five times and i just happen to knock the wires on the back af the main switch and it stopped hesitating so im thinking i might have a faulty switch. would you think that it might be the cause of the gas valve feed loss?

 

[matchstick]

Its not the switch i've cleaned the contacts and the boiler switches on without hesitation but still no feed to gas valve.

 

[ollski]

ok turn power on to the boiler and the fan runs slow speed yes?,switch in hw position and tap on fan gos to high speed?. your limit stats are closed circuit and frost stat open?

 

[kevplumb]

who is matchstick

 

[Jimmyjaffa]

Yes it all works fine accept for the gas valve feed which is my original fault,but whats doing my head in is that earlier i had a feed.

 

[ollski]

Yes it all works fine accept for the gas valve feed which is my original fault,but whats doing my head in is that earlier i had a feed.

That means it dont work!...need to know the exact symptoms and fail point...depending on if and at what point the fan does or doesn't speed up will tell us the area to look in also fitting a replacement (though wrong) frost thermostat got it running and putting back on the original reinstated the fault it might be worth a look around this point.. Take the wires off the frost stat and check resistance it should be open circuit.

 

[Jimmyjaffa]

Ok here we go, Switch on power to boiler,fan goes round very slowly, if i switch either to hw on/ch on the fan comes on full speed, measured for voltage at the gas valve wirers and only get 7.64v ac, so main boilers is not igniting. taken wires off frost stat (top right) and got (o f l) reading.

 

[ollski]

ok fan running full speed but no spark and pump running
voltage between 60 and 66 on pcb ac?
voltage between 60 and 62?
push in gas control knob wait 30 seconds and measure ac voltage across 55 and 56?

All tests in hot water mode with hot tap running.

 

[Jimmyjaffa]

hi i put it all back together last night and it seems to be working ok only the hot water doesn't seem as hot as it used to be especially upstairs but at least its firing up know and we seem to be getting there.