fan on but does not activate air pressure switch

[prometheus]

I have a Britony Combi SE Boiler which was installed in August 2003 it is a Heating and Instantaneous Domestic Hot Water Fanned Flue System.

It has been working perfectly until the past two weeks. Now the central heating works as before but once you switch on any hot water tap the boiler stops functioning completely with no heating and hot water. To get it running again I have to press "re start". Even after pressing restart if I switch off the hot water tap and then switch it back on again the boiler stops functioning regardless of whether the heating is on or not.
Looking at the flashing lights on the boiler and checking the corresponding section of the manual it states the problem is:

"fan on but does not activate air pressure switch"

Is this a problem I can deal with myself reasonably or should I let the professionals come in and sort it out.

Thanks a lot for your help.

 

[boilerbeasty]

I wouldn't pay too much attention to the flashing lights, they can be helpful but can be down-right misleading. For example when you have the heating on the fan will be running (and the APS activated as a result).
Does the fan run when you select hot water ? I found my system said the fan was running but the APS wasn't activated, but in fact the fan wasn't running at all. I tested the fan - it was OK. But the PCB wasn't switching power to it. Replaced it for 100 quid from HRPC and 15 minutes to fit with a screwdriver (and the power switched off and the cable positions carefully noted of course).

But don't worry ! If its less than a year old, its under warranty (parts at least - may be labour) from Chaff. Give them a call.