Ariston Microgenus boiler misfiring

I have a 4-5 year old Ariston boiler which works perfectly in the summer, but intermittently misfires during cold weather in the winter months.

The symptom: the gas valve opens and closes almost immediately.

The cycle repeats itself a few times until the boiler locks up, displays an error code (A99 if I recall correctly) and requires a reset to restart.

The problem occurs both on DHW and CH.

Does anyone have any idea of what the problem could be? I need to decide whether to get it repaired next time it plays up, or get a new boiler installed now...

You dont say which model it is!

Its only 4-5 years old so one would expect a life of at least 10 years.

But to achieve that full lifetime its expected that you will have it serviced every years.

It sounds as if you have not been having it serviced. If not then the adjustments which should be made at a service ( not a British Gas safety check but a proper service ) will probably sort it out.

However, the PCB on those models are not very reliavle and can often give rise to those type of faults.

Tony

Thanks Agyle, the model is Microgenus II 24 MFFI.

It was serviced a couple of years ago, so I guess another service wouldn't hurt...

Can anything explain that it only plays up in cold weather?

that would be because the boiler is a load of carp

Can anything explain that it only plays up in cold weather?

Click to expand...

Sure, it's common a few boilers.
Air/gas flow thing though so it'll need a Gas Safe Registered fellah to investigate.