radiators come on when heating off

[darrenj]

With the onset of the hot weather I have turned the heating off, but kept the water to heat twice a day, unfortunately the radiators still heat up when the water heats up. I really need to sort this asap as the house is like an oven!!!!!!!!!


I have a Potterton Nettaheat boiler.

Any ideas anyone?????

Thanks

 

[seco services]

your motorised valve is letting by.

 

[ollski]

Here comes the sun!!

 

[Veglen]

Hope you don’t mind me butting in but I have the same problem. I have a three way motorised zone valve and when switched for hot water only, the radiators are hot too!

Does the zone valve require replacing or could it be something else?

I can hear the valve moving to the water and heating switches but has little or no effect!


V

 

[ollski]

needs replacing. maybe of help if you are doing it yourself:
http://www.plumbingwoes.co.uk/midpos.html

 

[Veglen]

Excellent, thanks for the link too!

Thanks

V

 

[seco services]

the paddle in the bottom of the valve maybe worn or muck round the hole restricting paddle from closing fully, so radiators getting hot.

 

[darrenj]

Thanks for the replies.
But
Wher will I find the motorised valve??????

Looking at the link it looks quite an easy job to replace it but where do I find it??????

 

[darrenj]

I was going to change the valve this week, unfortunately I now have no hot water it is only tepid, can this be caused by the valve as well.

I have a Honeywell 3 port valve, can this be changed for any manufacturers valve, I have seen one in screwfix about £20 cheaper, can this be fitted????

I am now going to change it today, will this now fix the hot water problem as well.

Thanks

 

[ollski]

I was going to change the valve this week, unfortunately I now have no hot water it is only tepid, can this be caused by the valve as well.

I have a Honeywell 3 port valve, can this be changed for any manufacturers valve, I have seen one in screwfix about £20 cheaper, can this be fitted????

I am now going to change it today, will this now fix the hot water problem as well.

Thanks

If you have a honeywell valve you will only need to buy the ball and plate (service kit) and possibly a new actuator aswell if its an old style valve without the dimple on the top of the case.

 

[darrenj]

I changed the motorised valve today and checked out the system.
The valve has 2 lights on top, 1 for the hot water and 1 for the heating.
I turned the hot water on but left the heating off and the water light is on.

Unfortunately all but 2 of my radiators are still hot, even though each thermostat control on each radiator is turned down and the wall thermostatic control is right down.

Also the hot water doesn't get hot enough to have to remove my hand when running it. It does get hot but not as hot as it has been in the past.

Any ideas?????