I have a Glowworm boiler, and no changes made recently.
A few days ago my heating started coming on when set to hot water only regardless of the room thermostat setting.
After reading posts on here it sounded like my motorised valve was sticking/bust. So I think I've found it and attached a picture of it (some clown has installed a wall over it! - not me BTW).
When I switch to heating only the lever moves to the right, on hot water only the lever only moves to the middle and the rads stay hot. If I force it over by hand the rads go off as they should.
My question is - is this my problem and can it be replaced without draining down the system (there's no drain valves in this house!!)? Some posts have suggested replacing just part of it (the motor?) without draining down, but this depends on which unit it is. I don't know which one mine is, perhaps someone could tell me from the photo. There are only two pipes entering it as far as I can tell (unless the third enters from the back, which I doubt).
Any help much appreciated.
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A few days ago my heating started coming on when set to hot water only regardless of the room thermostat setting.
After reading posts on here it sounded like my motorised valve was sticking/bust. So I think I've found it and attached a picture of it (some clown has installed a wall over it! - not me BTW).
When I switch to heating only the lever moves to the right, on hot water only the lever only moves to the middle and the rads stay hot. If I force it over by hand the rads go off as they should.
My question is - is this my problem and can it be replaced without draining down the system (there's no drain valves in this house!!)? Some posts have suggested replacing just part of it (the motor?) without draining down, but this depends on which unit it is. I don't know which one mine is, perhaps someone could tell me from the photo. There are only two pipes entering it as far as I can tell (unless the third enters from the back, which I doubt).
Any help much appreciated.
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