Thermostat Position

[mbelectric]

Hello everyone,

My elderly parents have just had central heating fitted in their 3 bed semi. The installer put the thermostat in the lounge. Also in the lounge is a large radiator with no thermostat (all the other radiators have themrostats).

The problem is that the lounge (and kitchen) face South so get the sun all day. When they set the room thermostat to their desired temperature the heating didn't come on because the sun heats the front of the house quite well. However the rooms at the back of the house are still quite cold.

Should the thermostat not be placed in the (theoretically) coldest room, which would be in a back room and the radiator in the lounge have its own thermostat? There is also a small hallway at the bottom of the stairs with no radiator, could it not go there?

Fortunatkley the thermostat is wireless so it can be moved quite easily.

 

[D_Hailsham]

You may have to experiment to find the best location - easy when it's wireless.

I would not put it in the hall as that might never reach a sensible temperature if there is no rad there - unless you leave all the doors open; so the boiler will run continuously. Try the back room, but remove the head from the thermostatic valve so the valve is open all the time; this prevents the valve closing before the wireless thermostat has got up to temperature.

The lounge might now get too hot, but that's a problem which can be solved by a thermostatic valve on the radiator. When you have found the best room just swap the valves over.

If you find that one room refuses to get up to temperature before the wireless thermostat turns the boiler off, try closing the lockshield valve (opposite end to thermostatic valve), on the rad where the wireless thermostat is located, an eighth of a turn at a time. This will reduce the radiator output so it takes longer to heat up.

Just an afterthought Did the installer balance the system?

 

[mbelectric]

Thanks for the advice/tips.

I am not sure about the 'balancing' I will ask my parents. Would the installer have had to do something to balance the system which my parents may remember them doing?

 

[D_Hailsham]

Would the installer have had to do something to balance the system which my parents may remember them doing?

Yes
He would have gone round all the rads adjusting the lockshield valve to make sure each rad gets its fair share of the water flow. If not done properly the rads nearest the pump will get more water and starve the ones at the end of the run.

Read FAQ 2 and the link given for more info.

Some installers just do a crude balance by closing some valves one turn and others half a turn. This is not good enough when you have thermostatic radiator valves; the job has to be done properly using thermometers to measure the temperature of the water into and out of each radiator.

A quick check you could do is as follows:

Remove the thermostatic head from each radiator and fully open the wheel valve on the rad in the lounge.

Turn the wall thermostat up so all rads get hot

Check by feel the temperatures on both pipes of a rad. One pipe on a radiator should be noticeably cooler (10C) than the other. The hotter pipes should all feel the same and the colder pipes should all feel the same.

If the temperatures are reasonably similar then the installer has made an attempt at balancing. But if you find that some rads are noticeably different, then he has probably not bothered balancing the system. Some installers think it is not necessary if you have thermostatic valves on the rads.