We've came home last night to no hot water, no heat :-(
The pilot light on the boiler is lit, although it seems a little smaller than usual.
Rotating the boiler thermostat from off to fully on to off again seems to elicit the usual click but the burner doesn't fire.
Any thoughts anyone?
The burner will only fire if there is a call for heat from the room thermostat or timeclock.
Check fuse supplying CH timeclock/programmer is not blown and then, if you know how, check for mains across the gas solenoid terminals.
Owain
The main gas valve isn't opening. This could be due to:
Start by making sure that your programmer is calling for hot water, and that a fuse hasn't blown somewhere. If that is all ok, remove the fire and check that mains is actually arriving at the terminal block. Then, if possible, check that this is actually getting to the gas valve.
Boiler thermostat has live in on brown wire and then live out on white wire to gas valve body controlled by rotating boiler thermostat knob. Blue neutral is on gas valve body.
0v on white when boiler thermostat turned down. 240v when it's turned up. Based on that, I assume the gas valve has decided it's had enough. Does that sound reasonable?If it is, any thoughts on a supplier who can deliver quickly without fleecing me?
It may not be producing enough heat to make the thermocouple operate. Remove the pilot jet and give it a clean.
According to
Other sites (found by Googling on the Honeywell ID seem to have them at anything up to 100 quid!
I would have thought that, in that case, the flame failure device would operate and the pilot would go out too.
You seem to be under a misapprehension as to how the thermocouple "works" in relation to the multifunction gas valve Dave. The heated thermocouple produces an emf which drives a small current through a "hold open" coil on the inlet section of the valve. This supplies the pilot burner AND the main gas solenoid which opens when a heat demand is applied. If the pilot flame is present and hot enough to keep the inlet section open then thats it. If the thermocouple is not hot enough to keep the inlet valve open then it closes and the whole gas section shuts off including the pilot burner. Cleaning the pilot will be a good thing but is not related to the problem UNLESS there is a failure of the safety section to close properly although in this case the solenoid opening will rob the pilot of the residual bit of gas which was passing to the pilot flame and it will go out. Failure of the solenoid can and does happen albeit not very often so a replacement gas valve will then be in order
Not the case in my ancient Potterton Kingfisher.
That's the one!
Hmm. I hadn't found keeptheheaton and the cheapest I had found was £10 more than they want (but £45 cheaper than the most expensive!). I'll see if they will price match keeptheheaton when they open in the morning. Thanks for the help - appreciated.
That's what I expected/understood.
I can only imagine that that's what's needed. The gas valve is receiving power but isn't opening.
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