Biasi 24S problem - summer/winter setting - PCB ?

[brian_diy]

Hi,
Wondering if anyone can help with this.

Biasi 24S will not light with selector switch in the summer position, fan doesnt come on and pump doesnt run. If you move the switch to the winter position, the boiler lights ok, stays on for about 10 seconds then goes out. It then relights and stays on and appears to work as normal, radiators heat up ok.

Boiler lights when hot water is demanded with switch in winter position but nothing happens when in summer position.

I've checked diverter valve diaphrams, microswitches and temperature probes as per the service manual and they appear ok and I am now leaning towards it being a PCB problem.

Any one got any ideas.....?
Thanks for the help

 

[Agile]

It sounds as if the selector switch is faulty in the sunshine position. Its part of the PCB. Perhaps moving it a few times will clean the contacts.

It does not matter anyway because you can control the heating from the slider on the timeclock.

Its correct for an anticycling delay of up to 3-4 minutes when you select heating.

Tony