Programable roomstat a better bet ?

[Niscars]

I currently have gas (Ideal Elan II) ch with a single dial thermostat in the hall and a programmable timer switch controlling on off times. I currently leave the system on constant hw and ch and let the thermostat do its job. Trouble is we get too hot in bed .

Some advice please - would fitting something like a Drayton Digistat 2 or 3 which could be programmed to allow a drop in temp at night be better than setting the boiler to go off for a period during the night ?

Thanks in advance.

 

[breezer]

i am not a plumber or heating engineer, but reading these forums you have 4 choices

1) fit the stat you mention

2) fit trv's on all but one rad

3) turn the stat down when you go to bed

4) have heating turn off late

 

[Niscars]

Thanks Breezer,

Of the 4 options given I suspect that 1 and 4 are the easiest and cheapest to achieve. The key to it all really is which would be better in the long term for the system. IE, does it do harm to allow the system to cool down overnight by turning off the ch at the timer or is it better to allow a couple of degrees cooling overnight by using the digistat ?

 

[JohnD]

It seems to me that you are tipping money down the drain by running the heating all night to warm rooms you are not in. And what's more it makes you feel too hot!

It's more usual to let the timer turn the heat off at night. Let it come on in the morning so it's warm when you emerge from under the duvet.

 

[oilman]

You could also look at the Honeywell CM67 with optimising control which should save you even more, or if you like sophisticated kit, the Centroller 3000. (Search the net for these).

 

[nstreet]

You could also look at the Honeywell CM67 with optimising control which should save you even more

Not if its anything like the one I fitted over a year ago. I have been home the last few weeks an have been able to monitor its behaviour. The optimum start often fires up the system and brings the house to temp almost an hour and half before its supposed to. If the temp in the hall was at 10 degrees I could understand it, but it only needs to raise it 2 or 3 degrees at most, which should only take 15-30 minutes. Honeywell seem reluctant to get in touch to sort out the problem.

 

[Niscars]

Thanks all - I am wavering now. I am sure that I have read somewhere that it takes less energy to maintain the temp overnight than it does to heat the house from cool in the morning prior to getting up.

 

[JohnD]

You heard wrong.


(sorry

 

[Niscars]

Ah

Thanks.

 

[meldrew's_mate]

I currently leave the system on constant hw and ch and let the thermostat do its job....

Surely you don't leave the DHW on 24/7? You could do the rest of the World a favour AND save yourself some money by heating up the water only when you are using it, usually morning and evening. A tankfull of hot water going cool overnight is doing no-one any good.

 

[Niscars]

Er Yes I have based it ALL on the apparently erroneous notion that it is cheaper and more efficient to keep both House & HW at the right temp 24/7 !

Am I going to have to rethink the whole thing ?

 

[oilman]

nstreet, have you set up the CM67?

 

[nstreet]

Yep, been through the installer setup, originally when first installed and again yesterday, after restoring to factory defaults, both for the time settings and programmer options.

Still not much improvement, it seems to fire up way to early on optimum start. My wife is getting very annoyed at being woken up at 4:00am by the damn thing. Any ideas?

 

[ricarbo]

Concerning whether you leave the heating on 24/7.
The heat loss (your bill!) depends on the temperature difference between inside and outside. The bigger the difference, the bigger the bill.
Take the logic to an extreme - imagine you weren't at home for 6 months - do you think it would be cheaper to leave the heating on or off?!!!
I think the idea that it might be cheaper to leave it on comes from the notion that it takes a lot of energy to heat up a building from cold, because all the walls, floors etc have to get warmed up, whereas if you keep it going they never get cold, but it's false thinking.
The better your insulation, the lower your billswill be. If insulation is wet, e.g. rising damp it is very badly degraded, so fixing the damp makes a huge difference to your costs and comfort.
On a Danfoss TP7000, you can turn off the optimum start, can't you do that on the Honeywell?

 

[nstreet]

.
On a Danfoss TP7000, you can turn off the optimum start, can't you do that on the Honeywell?

Yes, but that defeats the object of buying a cm67 with opt start in the first place. The opt start is extra money with the Honeywell.

It was purchased to save money, as told by Honeywell. Either mine is a rogue one, in which case I would like it changed, regardless of whether in warranty or everyone with a CM67 with opt start assumes its doing its thing correctly, because they are not there to observe it#s odd behaviour.

Can't wait for the really cold weather, it will probably fire up tomorrow in preparation for the wintery blast this weekend