Hi, the pilot light will light as i have changed the thermocoupler and the main burner will also light but then you here a click from the gas valve which turns the gas off. Can anyone help please, Ian

Ian, April 2008

Just increased the jet pressure slightly (small screw inset in main control module (mid left )to stop flame sucking away when the main burner comes on and hey prestoits working fine. If when you switch unit on the flame draws away from the thermocouple even for just 1 second the main burner will not come on and the pilot light will go out -- could be my pilot burner nozzle is slightl furred up ... thanks for the heads up saved me £200 quid.... happy chappy !!!

Tezza123, October 2010

is a glow worm ultimate open flue low water content or cast iron

carol oneill, March 2010

check that the sight glass is secure as, if not, the burner pulls air in thro the sight glass hole pulling the flame away from the thermocouple.

Bill, June 2008

Thanks Tony boiler now working fine, top man.

Ian George, May 2008

Thanks Tony boiler now working fine, top man.

Ian George, May 2008

you will see that when you light piliot and main burner comes on the main flame goes all floppy and goes out this is due to main heat exchanger external fines being blocked up not allowing burnt fumes to pass through if the is case heat exchanger requires removing and power jetting clean
or
if pilot jet to small causingforce of main burner to pull flame from thermocouple remady clean pilot jet not with pin but with compressed air can or remove and blow water through

tony, April 2008