Wireless thermostat query

[gilford]

Any of you knowledgeable guys on here know the answer to this?

I've currently got a Honeywell DT92E wireless thermostat, but what with the price of oil nowadays I thought I would try getting a Honeywell CM927 so as to have timed temperatures in the house, keeping it at a constant temperature in the thinking it may actually save a few pennies!?

Am I right in thinking that the CM927 (although it comes with it's own receiver box which connects to the boiler) will pair with my existing Honeywell receiver in the boiler room?

Any info appreciated on the matter. Is my thinking correct re the thermostats and the constant temperature?

Is there a "better" alternative to Honeywell?

Thank you!

 

[D_Hailsham]

Am I right in thinking that the CM927 (although it comes with it's own receiver box which connects to the boiler) will pair with my existing Honeywell receiver in the boiler room?

Yes. You can actually buy the Room Unit on its own; it's the CMS927B1049

Is my thinking correct re the thermostats and the constant temperature?

That's debatable. I doubt if you would like to sleep in a bedroom when the temperature was 21C - unless you were ill. It's a case of comparing the cost of maintaining a constant temperature, with the cost of allowing the house to cool down and then reheat. If the house is well insulated it will only drop a few degrees overnight, even in cold weather.

You need to monitor your temperatures.

Is there a "better" alternative to Honeywell?

Not really, but again that's debatable. Honeywell do have a good reputation for quality and reliability.

 

[gilford]

Many thanks for your quick reply!

My thinking with the new thermostat is to set the night temp to say 18 degrees and the morning (when we are in) to say 21 and then drop to 18 degrees throughout the day when no one is home, keeping a steady temp and allowing the boiler to click on and off for short periods to maintain the temperature?

Also (yet another) question..........

Should I have all my TRV's set to 5 when using the thermostat to be more energy saving/cost efficient?

Thanks

 

[D_Hailsham]

My thinking with the new thermostat is to set the night temp to say 18 degrees and the morning (when we are in) to say 21 and then drop to 18 degrees throughout the day when no one is home, keeping a steady temp and allowing the boiler to click on and off for short periods to maintain the temperature?

Sounds reasonable, but it's worth checking how far the temp drops overnight and when you are out with the heating off. If the house is well insulated it may not be more than a few degrees. Use a Max-Min thermometer to check how low it does go.

Should I have all my TRV's set to 5 when using the thermostat to be more energy saving/cost efficient?

A setting of 5 will mean you want the temperature in the room to be about 23- 24C. If that's what you want, then set the TRV to 5. Most people set the stat to between 3 and 4, which is a temp of about 20-21C. (It varies from between manufacturer's.) Try setting the stat to 2 in the bedrooms (keep doors closed) and 3 in living rooms. Then see how you feel. If it's too cold turn up half a division and check again. You will find a setting which works for you.

If you have a TRV in the room where the wall stat is (you shouldn't) then you must set it to Max. If you don't, it could interfere with the room stat's controls of the boiler.

 

[gilford]

Thanks yet again for your help

My house is an 80's bungalow so not the best insulated!

My other thinking regarding the constant temperature is we have a bit of condensation in our bedroom, just in the top corner where there are 2 large external walls, a bit of black has formed there. I have had a damp guy round who says everything seems in order and to maybe try keeping it a bit warmer in there in the Winter months and also ventilate a bit more.

I'm struggling to find anywhere that sells just the room stat though?

 

[martyc]

There is also the CM921...the cm927 allows you set different temperature profiles for different days of the week....maybe overkill for what you want.

I have the 921 and i have installed them for others and they are a great bit of kit.

Re the TRV's:
Decide on a room that the stat will live in most of the time and turn the TRV to max in that room.
That room should be one of your living areas/hall(not near a door tho) as it should be a room you want as warm if not warmer than other rooms.

You can turn your TRV's down then to say 18 or whatever suits you in bedrooms.

Another consideration when using one such stat to control your boiler is that your rads are all nicely balanced so that your rooms heat at the same rate...you dont want to reach a nice cosy tem in your living room and the boiler to shut down before it gets everywhere else up to temperature.

Also a cosideration is what temperature your boiler works its most efficiently at(I think most are pretty efficient around 65 degrees but look up oyour own model as theres so many different variants these days...mine is old but good!!)

Marty.[/b]

 

[gilford]

Thanks Marty!

I have a Worcester boiler (new a couple of years ago) and doesn't really have a heat setting, just a dial which is similar to a volume knob for water and heating?

I've had both of these set to the 12 o'clock setting (pointing straight up)?