Which thermostat control unit for CH?

[kingofdawn]

hello,

I'm going to replace the thermostat unit which turns on and off the CH at home. Currently, I have got a very basic one which allows just setting one evel of temperature and that's it. I want to replace it with a wireless one so I can place in any room, adjust the heating level depending on time of the day etc.

The problem is that I'm not sure which one choose. The reason is that the current one has a huge variance of temperatures between the on and off actions. I.e. if I adjust it to 20 degr. it turns off the system at about 21-22. Then the temperature drops to about 18 before it realizes it's time to notify the boiler it's time to heat! You can imagine that variance of 3-4 degrees is huge and is also every uneconomical either.

I have checked number of different ones and none of them seem to have a parameter that would give the info about its threshold and temperature variance between on and off positions.

Now, I want to buy a wireless one. Can you suggest or recommend which one is a good one and does not suffer from a similar problem as described above? Or what parameter I should look at?

Thanks
S.

 

[D_Hailsham]

I want to replace it with a wireless one so I can place in any room, adjust the heating level depending on time of the day etc.

Do you mean that you want to move the control unit about, depending on which room you are in, or just that you want to have different temperatures at different times of the day?

The reason is that the current one has a huge variance of temperatures between the on and off actions.

That was typical of mechanical thermostats, though later ones only had a variance of about 2-3 degrees. This was due to the element which measured the temperature. Modern digital thermostats use a completely different way of measuring the temperature which is much more responsive to changes, so they usually have a variance of about one degree.

The Honeywell CM921 (24 hour) or CM927 (seven day) are probably the best available at the moment.