When you turn the thermostat knob under the fire up with the clock calling for heat do you hear a dull click or a clunk.If it is a dull click you need to check across the gasvalve with a multimeter where you should have 240v.If you have 240v then the solenoid on the gasvalve has gone.If its a really old Baxi Bermuda 572 it could be the stevens valve which i dont think you can get anymore.Heres hoping its one with the grey push button gasvalve.
Tony S
January 2009