gas valve or solenoid

[johnnyplumb]

i rarely do breakdown work, usually only installs.

got a call from a good customer, so thought i'd help him out
old baxi wm 60/3 rs with green button 4700e gas valve like this

initially boiler would'nt fire up, but after turning on/off a few times it fired up but then would'nt turn off, even after killing the power.
i'm thinking new gas valve, as it's jamming/ jammed open,

could the solenoid be faulty ?, anytime i see solenoids failing though, they usually dont open the gas valve
i know theres not much to these old boilers but i never had much time to spend, so going back tommorrow.

 

[mountainman]

I can't remember if that gas valve works on the principle of a relay valve.
If it does then a tiny let by on the solenoid will allow gas to pass.
You could strip and clean it but be careful not to damage the gaskets

 

[ambrosia]

it sounds like a solenoid but its a bit weird to be jammed open
did you test leads with a multi meter

 

[Atouchofgas]

Had these valves stick on numerous occasions, it's usually because the green button is hitting the plastic casing or the spring seizing under the button it's self as its not used that often

 

[tamz]

It is the diaphragm sticking inside the valve. You could do as MM says. It is easy to do, half a dozen screws.

 

[Leo21]

Play it safe replace the lot, there not that expensive. If stripping doesn't work your back to square one and will have to replace the valve any way.

 

[andyg0507]

same valve thats on a g/worm spacesaver, as said you could strip it, but far better to just replace imho

 

[diamondgas]

I'd replace myself ... Could be a blocked/restricted breather hole on the valve? Not worth the time messing with IMHO

 

[johnnyplumb]

i think i might open up the back of the gas valve and see if i can do anything with it.
probably end up replacing though. cheers guys

 

[andyg0507]

let us know how you get on jp.

 

[tamz]

Ease it open with a stanley

 

[diamondgas]

i think i might open up the back of the gas valve and see if i can do anything with it.
probably end up replacing though. cheers guys

LOL ... You take the plate off the bottom and then think.........! WTF! New valve required! :lol:

 

[johnnyplumb]

Ease it open with a stanley

lol, i'll make sure i've got my goggles on first though.

 

[stevetheplumber]

Ease it open with a stanley
i had to look twice to see if it was kirk suggesting this

 

[johnnyplumb]

in the end i just told him he needed a new gas valve, could'nt be @rsed opening it up
fitted it this afternoon and gave the boiler a good clean out at the same time, ended up a nice little earner,
wish all boilers where as simple as these old boys.

got the old valve in the van, might take a look inside it sometime :smile: