biasi boiler pcb buzzing

[katielouise]

Hi there,
We have been having problems with our boiler since we moved in and plan on saving through the summer to replace ready for winter.
One of the issues has been the PCB buzzing, the BIASI engineer who fixed something else on the boiler said that's what it was but said it was to costly to fix so just to ignore it until we're ready to replace. Previously the buzzing just happened now and then when the boiler was ignited and then stopped after a while.
However we woke this morning to a loud buzzing coming from the boiler, the boiler was not ignited just buzzing and when ignited it continues to buzz. I also noticed that the clock on the cooker is reset so I'm guessing there has been an electricity failure and maybey that is what's caused it?
Is there any way to remedy this?
Also if not then if we use to just turn on the boiler when we want the hot water and suffer the buzzing until we can afford to replace is this likely to cause any major problems?
Thanks in advance for any replies, this site has been a great help in the past I only wish I had somthing to contribute myself feel like a bit of a user lol!
Katie

Update: I decided to try and just turn it on let it buzz and hope for the best, did this and after around 5mins the buzzing stopped and fingers crossed now seems to be ok!

 

[Agile]

Its not likely to be the PCB buzzing.

More likely to be the gas valve main solenoid if it buzzes all the time. That can often be stopped by tapping it from the front on the solenoid casing.

More often if the buzzing varies with the power output being loudest when first turned on the its a buzzing from the modulating coil on the gas valve as a result of a failing C1 on the PCB. This is a 1000uF 35v capacitor and can be changed by any competent electronics engineer. A TV repair man for example.

I suppose that Mick Fletcher is right that the PCB costs about £100 and is hardly worth replacing on an older boiler.

Those 24S boilers are totally repairable though and can be kept going for at least another 5-10 years by anyone with a good engineer.

Tony