My boiler has been working fine, used it last night before bed with no problems or noises.
Woke this morning no hot water or heating- F1 fault. Tried reseting- no good. Checked gas flow to boiler seems healthy enough, igniter/sparker fires but no gas flow to manifold. The main solenoid on the gas valve energises and magnetises also checked the monureg solenoid next to it (not sure what this does- think it senses pressure variations?) it has voltage to it but thats as much as i can say. Stripped out valve to see if there were any obstructions- none to be seen. Checked pcb nothing there either, no dry joints or suspect components no bad smells ... nothing.
Could this be a mechanical failure of the gas valve or have i over complicated a simple problem?
All advise greatly appreciated.
Regards David

ps my next door neighbour has just had gas plumbed into their house from the main in the street a week ago??

David, May 2008

Thanks for your reply T.
I recon it's definitely the gas valve. I've got 240v on the main solenoid with a nice healthy "clack" noise when energised and that monureg coil has between 10 and 13v depending on demand.
What voltage would you expect on the monureg coil?
If it is the valve which it certainly looks like, why would this fail, it's a pretty simple thing from what i can tell and it's not exactly hard pushed?
Any how i've got a friend of a friend popping round tomorrow (corgi registered) to have a look- I hate getting other people to fix things.
If it gets replaced i'm going to open her up and find out what the problem was.... knowledge is power!
Thanks in advance,
David

David, May 2008

Hi David, I would be thinking gas valve has failed. The monureg solenoid is for modulating the gas pressure according to demand. Just confirm your voltages from the pcb to the gas valve (ie. the board is signalling the valve to open) then connect your manometer to the inlet side of the gas valve, check the standing pressure, turn off the gas isolator under the boiler and then turn the boiler on and demand, when sparking occurs does the pressure now get sucked from the manometer? (if so the gas valve did open and is working and this still maybe a pcb problem) the boiler will lockout then as you still have isolator closed.

Just remember only a qualified gas installer is allowed undertake the work you are doing!

T, May 2008