Radiator thermostats

That should be all but the radiador where the room stat is, usually the hallway

you had them on every radiator then if the house gets hot all the rads

The bypass. May or may not be needed. It depends on the setup.

A drain down is needed, the TRVs are usually a straight swap when the system is drained down.

Adam

They should be fitted in every room except the one with the room 'stat in (usually the hall or the living room).

Not if the room 'stat turns off the boiler first. If it doesn't then the boiler is on all the time the programmer says it is, and you're wasting incredible amounts of gas (or oil or whatever).

I must remember to read all the posts in a thread before replying; I've just said the same thing only 11 hours later!

Can it be done with one of those pipe freezing kits? I've _replaced_ a TRV without draining down.

Thanks guys, I've just discovered that all the rads are hot even with the wall thermostat turned down fully. This might explain why this particular room is too hot. It's got the airing cupboard one side, bathroom the other (it's one of those systems where the bathroom rad is on constantly), plus the rads don't seem to be turning off no matter what the main thermostat is telling them.

The programmer is set to "continuous" for heating and water, but the thermostat doesn't seem to be controlling anything. We have a problem!

What system do you have?

Adam

I'm not sure. We have a boiler in the kitchen which supplies the water and the heating, a hot-water-tank in the airing cupboard along with the programmer, and a wall mounted thermostat in the hallway. That's it, really. I've left the programmer on "continuous" and was under the impression that the boiler would only heat the rads or the water when they needed it.....

In your scenario, do you mean I should turn off the heating at the programmer, or the hot water? The rads are still hot despite the thermostat being turned all the way down, so I'll go and turn the heating OFF at the programmer and see what happens.

Have you any zone valves in the airing cupboard?

Adam

We've got a 3-way valve that was replaced a few months ago.

A Y Plan set up?

Try calling for HW and CH on their own and see what happens. You should be able to get both HW and CH to work independantly of each other.

Adam

I've turned the CH "OFF" on the programmer but am waiting to see if the rads cool down.

OK, the programmer has been OFF for the CH for half an hour and all the rads are all still red-hot.

Are you still calling for HW?

Adam

Yes. Kept the CH off at the programmer, then turned the hot water off at the programmer an hour later, and the rads went cold. Turned the HW back on, rads got hot again. CH still off at the programmer.

No idea how this system works, but I can hear the valve motor run when I turn the hot water on at the programmer, but there's nothing when I turn the heating on, whether the water is on or off.

To be honest, I'm not sure if this is recent, or whether it's been since we had work done on the system. We had a problem where the boiler stopped firing up, they replaced the 3-way valve and the programmer (under insurance), but now I'm wondering whether they've wired everything up correctly or whether we've had a failure since then. It's only since the weather is getting warmer that we've noticed how hot this room is.

A few tests for you to do if you have a multimter. The yplan diagram is here

Then call for HW and CH. The white wire should go to 240V when you turn the roomstat up.

Adam

I didn't fancy sticking probes into live electrics(!), so we called the fella out again... it was the mid-position actuator apparently, he just swapped it and all is well. Because it was one of the parts he'd swapped a few months back, it was covered. Thanks for all the help.