Myson Apollo HW but no Heating

[unkle]

All of a sudden my heating does not work.

HW is fine boiler fires no problem, but CH does not fire.

Any ideas?

Cheers

 

[gas4you]

Have you 2 x 2port zone valves or 1 x 3 port valve. If so I would suspect 3 port head or ch 2 port valve head.

Checked room stat?

 

[unkle]

Checked room stat and all ok,

Just found the mid position valve (assume thats what you mean by a 1 x 3 port valve) in the airing cupboard and it seems to be stuck on the W, there is a plstic type switch but it won't seem to budge.

 

[gas4you]

If you can, remove head and see if spindle is stuck. If not replace head. If it is stuck then new complete unit needed

 

[unkle]

Cheers, i'll have a look in the morning.

I can no move it manually to the "M" position, but it just slowly drifts back to W, what would happen if I wedged it in the M piositio for a while?

 

[gas4you]

heating & h/w should get hot but with no thermostatic control. If you do this and rads get hot then this proves valve faulty

 

[unkle]

Cheers,

Yer held it open for a few minutes and the rads warmed up, so it must be that then - couldn't be anything else though could it??

 

[gas4you]

Could just check that stat controling it is sending 240V to it first