I'm passing this request along for a friend, so please forgive any ignorance or mistakes on my part. The problem is with a Ravenheat CSI 85A combi boiler... it won't light (duh!).
The unit was self-installed, and has worked without problems for the last few years. A week or so ago, the unit would no longer light reliably. Turning on the hot water tap became a pot luck affair. If you left it running for 20-30m, you might get hot water eventually. A visual inspection of the boiler during this time showed the boiler lighting for a few seconds, but then turning off again. It would, on occasion, decide to light properly and deliver hot water untill the tap was turned off again.
Since then the problem has gotten worse. Now the fan works, but the pilot light will not light and the pump will not run. The fan only works intermittently though.. it will come on for a few minutes and then turn off for a few minutes.
The ignition board has been replaced, but it made no difference.
Does anyone have any advice on what may be wrong?
Thanks in advance.