Thermostat on wall backing on to airing cupboard

19 Mar 2011
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United Kingdom
I moved into a new built house over the summer and am looking for an opinion on something that may be an issue with our heating. Just want a sanity check before speaking to the builders. I'm not planning on diying anything.

The main thermostat that controls our upstairs is in the master bedroom, all other upstairs rooms have thermostatic radiator valves. Downstairs has a separate timer that controls hot water and underfloor heating. Problem is that the thermostat is mounted on the bedroom side of a wall that backs onto the airing cupboard, so always seems to read higher than the room temperature measured by a separate thermometer. I'm thinking the warmth from the hot water tank is affecting the thermostat.

My concern is that if the thermostat is kept warm by the water tank the rest of the upstairs radiators won't get heated. Does this sound realistic? Not really been a problem yet, but winter is coming.

Anyone got any thoughts or similar experiences?I'm thinking about asking the builder the replace the controller with one with a wireless thermostat we can put elsewhere in the room.
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Its not necessarily a mad idea, if its mounted on the wall of the Cylinder cupboard then it very possibly will read a little higher than it actually is in the room, however dont go by a single other thermometer to determine that its reading wrong, you can have 5 different thermostats/thermometers lined up and each will give a different reading by a few degrees.

Personally, I'd give it a month or two to get colder and see how it heats, if its an issue turn it up a couple degrees and then speak to builders, typically they will just state that its fitted to the architects plans and theyve done their job as specified.

Do you know what make the thermostat is? or put a picture up, some of them have an offset that can be adjusted to show a different room temp for these exact type of issues (whereby you can set it to always read and act 2 degrees cooler than it thinks it is)
If it were me I'd just crank the stat up a couple of degrees, or until room temperature is 'comfortable'.
It's a Honeywell CM907. I know the kind of setting you mean about offsetting temperature, but not sure if this can do it?

At the moment I'll keep an eye on it, and if need be just turn it up a bit higher until it is right by feel. Will see how it behaves in colder weather.
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Good to know, I'll print that and keep it somewhere. The instructions we have are the 'user' version I think and didn't mention that.

Thanks for your help.

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