Advice Needed Please on Room Thermostats (I've overgoogled again)?

Lizbetty

Hi everyone!

We've just moved house and are coming across a lot of things to do

The fact that we're on a standard tariff with British Gas until Scottish Power transfer us (if they ever reply to us, it's been weeks) is making me conscious of how we are using the heating.

We have an old style boiler, which has a Horstmann timer (which we replaced as the old one was broken..) and a Danfoss RMT230 in the hallway which has no numbers on it! It looks like they've been cleaned off which is distressing me a lot..I have no idea what temperature we're setting it at.

All of the radiators bar the bathrom and ensuite have TRV's fitted. The room thermostat is sited a narrow hall with the radiator (inc TRV) on the other wall at the other end, it's not a massively long hall.

I had come online with the intention of buying a new thermostat, then I started googling...

The one we have has two wires. I was going to buy a direct replacement, and then wondered whether to go for a digital one. Then as I was googling, I started to realise that the TRV on the hallway radiator may be an issue.

I'm just a bit confused now if I'm honest

I want to make sure that we are running as economically as possible with our current set up - we can't afford a new boiler at present, the house is a 1930's detached and is a lot bigger than our old place, and so the cost of heating it is keeping me awake on a night.

Can anyone recommend a good room thermostat please as a replacement for our two wire RMT230, and also could anyone please advise whether we need to do anything about the TRV on the hall radiator?

All advice is welcomed, I'm so confused by things as we have a lot of broken stuff that I have to learn about and this is one of many new subjects for me! I'm really grateful for any suggestions.

Thanks in advance,
Lucy

I_have_spoken

A while back, I had a basic roomstat which energised an old-skool open-flue boiler and immersion tank that had a 24hr CH/HW programmer in the airing cupboard.

I refitted that with a in-room Digistat 3+ thermostat/5-2 day programmer and remote receiver.

The receiver needs a 240V mains supply, then the Common and Switched Live connections on the receiver connect to the wires that now go to the hall thermostat. In my set-up there was a wiring block for all this which connected to the boiler and 3-way valve. I set the CH on the old programmer to 'always on' so effectively the Digistat 3+ had complete control of the CH.

I moved the sender unit into the lounge, and just set the TRVs to max. Ideally they should be replaced by simple valves, but that set-up worked for years!

matelodave

one of these should do the trick http://www.ebay.co.uk/itm/like/280744225688?hlpht=true&ops=true&viphx=1&limghlpsr=true&lpid=101&device=c&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0&ff12=67&ff13=80&ff14=101
they aren't ever so expensive. They will allow you to programme different temperatures at different times of the day. You can put the receiver close to the boiler and the thermostat part can then be located wherever it's most convenient.


It's installed as said above and you just set the existing timewitch heating to always on - the programmable stat then does all the timing and temperature control

Pincher

If it works, don't touch it. You can always calibrate it roughly by using a mercury thermostat.

The TRV in the hallway is only an issue if you end up with a hot hallway and a cold house. Reduce the flow using the lockshield valve, and keep the TRV on maximum, so it behaves as if there is no TRV.

st999

You can always calibrate it roughly by using a mercury thermostat

My thermostat only has 0 - 9 on it and I calibrated mine using a digital thermometer with a remote sensor.

Now I know that 6.5 keeps the lounge at 22 deg C

A.Penny.Saved

The numbers or temperature on the old thermostat were probably totally useless anyway, they usually are totally incorrect. Numbers showing a graduation can be helpful so you know where to position the dial but a temperature is usually too inaccurate to be useful in my experience.

Your better off using a thermometer, old style mercury for accuracy if you can still find one. Cheap digital ones are usually too inaccurate just like the digital thermostats.

As you indicate, there shouldn't really be a TRV where the thermostat is located, although it could be useful if you have a thermostat situated in a different location. Therefore leaving it open, set to high is the best option as already stated. If you do get a wireless stat, the hall TRV could still be used after the wired stat is replaced. ATM just keep it set to max temperature so the stat does the work. You can always keep the hall temperature lower using the TRV if you stop using the wired stat.

Personally I dislike wireless gear because of the added electromagnetic radiation and the harm it does to health. However you probably already use mobile phones, which I don't, so what is one more risk? However they are versatile which is their main benefit apart from not needing wiring in except for the receiver.

Goldfinger09

As for room 'stats, go digital. These mechanical / analogue stats should be banned now. I got a Salus one from Toolstation for £24.


I replaced our mechanical one years ago, a saw a massive difference in heating - the 'peaks and troughs' between the heating going on and off was amazing, and we even saw a drop in gas usage.

Lizbetty

Thanks so much for your replies. Sorry for the delay but we had a massive leak from our electric shower upstairs (a valve had gone and it was peeing down the back of the tiles, into the kitchen!). And so that's taken priority over the thermostat. It seems to be one thing after another at the moment

I think at some point a wireless thermostat is the way forward, the plumber/electrician who came out echoed what has been said in that we should live with it for a while and see how the bills turn out, and get used to it before we start to pay out for new bits and bobs.

He also had a look at the layout and said wireless was a good option with the layout being so odd, and as there's trv's in most rooms.

Thanks for the links too - I've bookmarked this and when we're finished forking out on emergencies (will that ever happen??) then we'll be looking at the Salus thermostat.

Thanks so much again for your advice, I really appreciate it.

Lizbetty

Hi,

I've taken the plunge and ordered a Salus RT500RF which should be here tomorrow.

I was a bit concerned about the hot water, but it seems that the Horstmann programmer we have will allow us to keep the CH on 24 hours so that the Salus will control the CH and the hot water will run independently on the Horstmann timer, which was a nice surprise (my old Horstmann programmer would only let us have the hot water on on it's own, or CH & HW together).

I am anticipating some swearing from my husband when it comes to the wiring..

Our current Danfoss thermostat has two wires. I've had a look on the internets and there seems to be no problem with him taking the current old Danfoss analogue thermostat off and wiring up the receiver for the RT500F. I have a concern about the wiring, as it mentions that we need to do something with a wiring loop if the boiler is 230v.

I want to avoid that disappointing moment where he wires it up and the boiler doesn't work :rotfl:

Our boiler is a Baxi Solo RS model. It says in the manual in the technical data section 'electricial supply 240v - 50Hz fuse 3A'.

I did think that wiring the new thermostat up may be a simple job but this extra loop wire is worrying me a bit, it does mention that this would be necessary for 230v boilers...I'm *guessing* this means we won't have to worry about the loop? Or does it mean 230v and above? 230v seems so specific, I don't understand why.

I'm a bit confused. I'm sure my husband would be fine but I feel I need to understand it a bit better myself in case of any issues.

Thanks again for any advice you can offer,

Lucy

Lizbetty

I'm actually excited about getting this new thermostat btw, I think I'm wanting to make sure it all runs smoothly when it arrives. I'm a bit fed up with disappointments in this new/old house

apositivethinkingcat

Having the thermostat in the room that is most used is the best way, a hallway seems a poor place for it to me. A portable one sounds ideal. Just remember to turn off radiators in unused rooms, I turn mine off in bathroom, hallway and during the day the bedroom to avoid heating rooms that aren't in use and shut the doors on them.


I'm impressed at the moment that I bought some thermal curtains and that they actually work! So if you can get those for windows and some doors you can trap heat in the rooms you want to keep warm really well.


Let us know how the new thermostat goes. It looks pretty fancy!