Got hot water but no central heating!

[SimonT1959]

I have a problem with my central heating.The boiler is not firing up when i turn the thermostat up. The thermostat clicks but nothing else happens. The hot water is fine. The boiler is a Potterton profile.

I suspect that the most likely cause is the motorised valve. This is a Honetwell one. Is it easy to change and can it be done "dry"?

Would welcome any help on the matter.

 

[Terry7556]

read boiler FAQ s at top of page especially no10 and 17.
the top of the valve may be able to change dry, if the silver box has a bump on top.
if you have to change the whole valve you need to drain down

 

[75pete]

First , try moving the leaver on the valve, its a spring return so should move back.
If the valve silver cover has a dimple then the head can be removed without the need to drin the system. I think if you look at FAQ, you will see more.
From what you already say, it would point to the valve as the problem.