My boiler has an intermittent fault. It fails to fire up every so often. When this occurs, taking off the low pressure pipe from the air pressure switch resets the switch to neutral, the fan starts running and the boiler fires up. Replaced the pressure switch a year ago and all worked fine for a while but now same problem occurs. Don't think valve has failed since after reset, all seems fine for another couple of days. Don't understand how vacuum can remain without fan running.

Wilko, November 2008

Have a Worcester boiler will fire up fine but time to time when I put hot water on will go off altogether , fan and pump still run but no ignition , reset and is fine for a bit , any idear what problem is ?

Craig, November 2013

Replaced the fan which seems to have helped but just now after 2 months it had the same issue again. Found a drop of condensation in the vacuum hose which possibly could keep the vacuum valve engaged. So no real fix. If I get really fed up with this, I might start looking for new boiler which definately won't be a worcester anymore!

Wilko, February 2009

just wondered if you've had any success?? I have the exact same problem with my 28i RSF. Have replaced the air pressure swith about 2 years ago, and all the following in the last 6 months ; control board, thermostats, gas valve connector (to pcb) still fails to ignite quiet regularly.

benj, January 2009