This morning my FER Hawk II boiler ignited when the hot water tap was turned on as normal. However the water quickly ran cold and on inspecting the boiler the pilot light had gone out. I relit the pilot and turned the hot water tap on again, the boiler ignited again and burned for about 10 seconds before going out. During this the flame weakened gradually (in colour and strength). I repeated this process several times, also by putting on the central heating, but with the same result each time. The pressure remains constant at 1.5 bar. I have also bled the system. Can anyone help?

John 2, December 2009

I have had British Gas out three times in a week. Same problem...

They fitted the water pump
Thermacouple...
New ignition and an electrode...

Your pump has backed up therefore your boiler cannot switch back to the Central Heating part and because its running on the hot water side, it is over heating and therefore the pilot light is being extinguished as a safety cut off.

Word of warning. The first engineer came out and lit it with his cigarette lighter and left me with it... my partner removed the cover and confirmed my conclusion as there was no "spark" so how did he light it...

The second engineer much more helpful, replaced all of the above... however I have a carbon monoxide leak now and am unable to live in my home. Am awaiting a call to say he can find a new casement for the boiler, if not that sheet of metal which has buckled will now cost me £2-£5K to replace... so watch these enginners like hawks!! British Gas employ cow boys too sadly! The Carbon Monoxide has been escaping for years and not one of them picked up on it!!! They have been servicing it etc and saying it is safe! I'm lucky we wake in the mornings!

S Quinn, January 2010

sorry my answer stated is for mark williams.

gavin, December 2009

sounds like the expansion vessel could have gone, if you pressurise boiler to 1.5bar and if the pressure increases quickly to over 3 bar while the heating is running, the expansion vessel needs replacing.

gavin., December 2009

Just had my hawk 2 replaced by a ferolli optimax because of same reason as you mark. Plumber changed pressure release valve which worked for about 2 months. What a difference with this new boiler though!!

Chris, December 2009

No Idea But yesterday mine had no water in it and gauge showed 0 bar. so re-filled to about .80 bar. Turned on heating pressure shot up to well over 3 bar. Bled system no air.so drained it down untill gauge read 3 bar.Woke up this morning to a cold house yet again no water in system so now at a loss. So can anyone help
Cheers
MarkW

Mark Williams, December 2009