I have a Vaillant combi boiler. No hot water today, heating is working and there is cold water. Can anyone tell me what problem is and how to fix it? thanks.

angie, December 2010

when running hot water the water runs hot to start with for about 2-3 mins then runs just warm

sonia, December 2010

hi angie...soz about last msg...i ment the right hand side & not the left...good luck

mike, December 2010

can't see how the pipe had 2 be cut as the heat from the boiler should keep it from freezin...if you look at the front of the boiler with the door open and the top cover off,,, down the left hand/side you should see the valve i was on about.? if you look 2 the left of that there's a small switch called the micro/switch..( has 2 wires come'n out of it ) its a small block with like a thin tin strap across it.... as you call for hot water a small like paddle moves down within the valve which makes contact with the micro switch...have a look to see if you can see this happening when a hot tap is open'd..??...best 2 get some1 to open the tap while yr at the boiler......4got to say that you need to drop the front panel down 2,,,,should have 1 screw at the top of it,,,,( panel is the 1 with the green knobs on it )....

mike, December 2010

Thanks Mike. No, still no hot water when heating's not on. Had a gas engineer out to have a look at it - he said it was a frozen outlet pipe so he cut it off but still no hot water. I suppose i will have to wait till the weather improves and the pipe defrosts.

angie, December 2010

no hot water on 10 year old Vaillant turbo max; has been bit iffy last year - sometimes turn on hot tap 2-3 times for boiler to fire up for hot water; heating fine; problem same whether heating on or off.
Help please

keith, December 2010

could be diverter valve....there is a kit you can get from a good stockist... £20-£30....but make sure you get a compentant plumer 2 do the work 4 you''''.....do you get hot water when yr heating is switched off....???

mike, December 2010