Two rads on with HW only !

lauriedthompson · Posted: Thu Jun 07, 2007 5:19 pm Post Subject: Two rads on with HW only !

Hello,

When I switch the hot water on two rads ( One downstairs in the conservatory and one in a bedroom ) heat up. Can anyone explain what might be happening and whether I can sort it myself?

Regards

Laurie

JohnD · Posted: Thu Jun 07, 2007 5:28 pm Post Subject:

Have you got a room thermostat?

What options does your CH timer/programmer have?

Photos would be helpful.

Do some of your radiators have thermostatic valves?

lauriedthompson · Posted: Thu Jun 07, 2007 7:22 pm Post Subject:

Hi John,

Thanks for the reply. We do have a room thermostat located in the living room. I change the programmer myself ( the plumber told me it was a simple process ) from a old glowworm to a Drayton Tempus 7. The boiler is a Vulcan Continental. None of the radiators have thermostatic values although all can be shut down.

Most of the radiators have been replaced over the years, but the two that are heating up have not.

Does this help? do you still want photographs?

Kind regards

Laurie

JohnD · Posted: Thu Jun 07, 2007 7:51 pm Post Subject:

I expect you have a motorised valve beside either the boiler or the hot cylinder, that sends the primary circulation around the cylinder and/or the rads.

Quite likely this is worn (allowing hot circulation to escape and go round those rads) or faulty (not closing properly.

If you can find the electric valve and see how many of the pips connected to it are hot, this will give you a clue. The pictures will help us see how the installation is done.

I have never had to fix a 3-port valve but someone will be along in a minute who knows the drill (I amnot a pro).

look for

with two or three large copper pipes going into it and an electric cable.

there is also a possibility that your programmer of room stat are calling for Heating.

As one of the hot rads is downstairs I think it is a worn 3-port valve, not gravity circulation.