Potterton Netaheat Electronic 6-10 Won't Ignite?

Hi all,

I have a Potterton Netaheat Electronic 6-10 boiler that is on the blink. Usually when it starts up I hear the fan start running for a couple of seconds, there is a click, then another click and the boiler lights. For some reason now the boiler ignites fine the first time however after a couple of minutes it cuts off. When it then starts again it won't ignite any more. I hear the fan start however there are no clicks and the fan switches off again. The boiler then continues this cycle of the fan starting, running for a couple of seconds and the stopping.

The irritating thing about this problem is that it is intermittant. One evening it will work fine, and the next it won't. I have had a guy out to look at it twice now (on the second occasion he serviced it) however on both occasions the boiler was working fine so he couldn't find a problem with it.

Any ideas?

Regards,

Rob

PS - I know that this boiler is getting on a bit, however I am due to move house in two weeks time so don't really want to have to replace it now.