Ours done this the other week and was off for a few days then it seem to fix its self? :S hot water now works mint and gets warm much quicker

yup, water off, find a drain valve, will normally be on a down stairs radiatior, push a hose pipe over it and crack it open, when most of the water is out open the vents on the rads upstairs, they should make a sucking noise, this will make sure all the water is out of the system

next turn off the power supply to the heating you may have a fused spur near your boiler that should isolate the lot.

after that its just a case of undoing the compression nuts on the valve and replacing it, then re conecting the flex to it

shut the drain off and the upstairs vents, turn the water back on and fill her up, check for leaks ect

with old systems the twat is draining down and filling back up, they can be really slow to fill sometimes

Aye il easily tackle anything ( time served production mechanic) as long as waters off and i cant flood the house or electracute myself im happy if u have some directions?
Bled tank a few times and gettin a jet of wAter which im just having to catch with a towel

yeah thats the hot water circuit, goes in the high up and comes out lower down

if there is no air in that then it looks like its the diverter valve they are easy to change one everything is drained if you wat to tackle it your self

System is gravity fed too, bleeding from the hot water tank in the cupboard upstairs where theres a pipe coming up from half way up the tank with a bleed point at the top

Theres a bleed point at the tank which il try a few times, havent seen any of the air vents though

if its a gravity system its very very likely to be an air lock

you could have a look round the pipework to see if there are any manual air vents, these will be a brass fitting on the end of a piece of pipe stuck high up, they have a knurled top on them you can undo by hand or with grips / pliers, you should try that first

Diverter Valve - exactly the same happened on my Glowworm - it was repaired under warranty as a known fault!!!

MattK is your man anyway :thumbs:

[Edited on 12-11-2010 by LiVe LeE]

Just found out from my Mum this has happened ever since the hot water tank was drained so must be an air lock

Iv bled the tank incase it was airlock. Getting hot water but itz likely from the immersion heater being on earlier. Will investigate further in the morning

Diverter valve stuck?

Some info:

The "diverter valve" is an electrically operated valve which switches the hot water flowing from the boiler to the radiators or hot water cylinder depending on which thermostat is calling for heat. If both are calling for heat at the same time the valve will assume a 'mid-position', sharing the flow between cylinder and radiators. The diverter valve is sometimes called a 'mid-position valve' for this reason.

I aint no plumber though....

[Edited on 11-11-2010 by _Allan_]

Any idea which valve? Waiting for mattk the resident plumber to see this

Sounds like the valve has gone

That's what the guy said to my mum when hers did the same

When turning on the hot water tap theres only cold water coming through, although heating works fine so boilers ok
Can get hot water using the immersion heater fine
Gravity fed system from loft, hot water tank in bedroom upstairs and boilers behind the gas fire in the living room, ex council house

Any ideas what i could try myself to get it working?