my combi boiler at the moment when switched on to run doesnt come on straight away & can take up to 15 mins to do so. also the hot water wont come on until the boiler has fired up but sometimes it will then when the boiler is off the process repeats itself!

any help greatly appreciated.

rich, November 2008

This sounds like a flow sensor on the way out.
Intermittent faults are very hard to pinpoint especialy with limited information.

wayneburgess@hotmail.co.uk, November 2008