when the heating is initated for the time clock it can take up to 15 mins. before the boiler fires, although the pump is running all the time

Terry Harper, December 2008

Seconds after entering my previous reply the engineer knocked my door! He brought me a spare Pilot & Electrode Kit (£32) as a precaution against the existing injector becoming partially blocked again - the service book says not to poke things through the hole to clear debris as he did.

He's in Winnersh, Reading Berks if you want his details.

Peccavi, December 2008

I have recently had a similar problem - now cured.

The fan would run and the pilot would light eventually but the burner would not burn. To begin with it was perhaps two minutes delay and over time could be as long as two hours before burner ignition. I had a spare PCB and changed it but it did not solve the problem.

The pilot flame was too feeble to properly generate enough heat to tell the PCB to open the main gas valve.

An engineer removed the pilot injector and cleaned it (£35 for cash) and now the pilot flame is good and hot and the delay time is about 5 seconds. The spark electrode now glows bright red when the boiler runs.

This on my Potterton Profile 100e - you don't mention your boiler?

Peccavi, December 2008