Thermostat Settings

ZolaBuddy

I have a Baxi combi boiler, with an old school thermostat in my hall along with a radiator a little further down. I keep all the doors that lead into the hall closed, and set my thermostat to around 20C of a winter's evening.

Am I right in presuming that the thermostat switches off when it reaches 20C based on the radiator in the hall even if the temperature in my living room next door is only 18C?

And should the TRV setting on the hall radiator be fully open (6)  or somewhere in the middle?

I always get a bit muddled about the right settings to keep my living room and study room warm enough but as economical/efficiently as possible. And I always thought that if the thermostat reached 20C in the hall it would switch off to the detriment of other rooms!

andyhawes

Yes the thermostat will register the temperature in the hall where it is placed, it won’t be aware of the temperature in the living room.

 I’m not sure about the valve on radiator in the hall but seems sensible to have it fully open, however someone may have a better suggestion.

Petriix

If your other rooms aren't getting warm enough then simply turn down the hall radiator a little until you're achieving the right balance. Don't turn it down too far (or off) otherwise it will never reach the set point temperature.

Reed_Richards

No I would go with having the TRV fully open.  Or at the very least, at a setting which will ensure it remains open at any temperature you might want to set on the hall thermostat.  

markin

Your not meant to have a TRV near the thermostat, so it should be fully open. If the other rooms are not warm and the TRV's are at max then set the temp to 21c, or install bigger rads.

Gerry1

Move the thermostat to the living room, nobody lives in the hall !  You can then make a saving by turning down the TRV in the hall.

FreeBear

Gerry1 said:

Move the thermostat to the living room, nobody lives in the hall !  You can then make a saving by turning down the TRV in the hall.

And get a programmable thermostat that allows you to set different temperatures depending on time of day & week. Which ever room you have the thermostat in, you need to make sure the TRV is open all the way (on No.6).

Zandoni

If a programmable thermostat is not an option then the TRV must be fully open, if the rest of the house is cold turn up the thermostat and leave the TRV fully open. A TRV shouldn't have been fitted to that radiator in the first place.

ZolaBuddy

Thanks for the feedback.
The radiator in the hall came with a TRV when I bought the home. I did read somewhere that TRV radiators shouldn't be in the same room as the thermostat, but there you go.

I have thought about a wireless thermostat, but I guess I'd have to get a plumber or a spark to fit one.

Does the lockshield on the other side of the radiator make a difference? I have most of them half-open. I do bleed the radiators at least once a year, but now I'm trying to make sure they're as efficient as possible.

Zandoni

Here’s some good advice on balancing your radiators https://youtu.be/QUWbxccVDpc

Bendy_House

ZolaBuddy said:

Thanks for the feedback.
The radiator in the hall came with a TRV when I bought the home. I did read somewhere that TRV radiators shouldn't be in the same room as the thermostat, but there you go.

I have thought about a wireless thermostat, but I guess I'd have to get a plumber or a spark to fit one.

Does the lockshield on the other side of the radiator make a difference? I have most of them half-open. I do bleed the radiators at least once a year, but now I'm trying to make sure they're as efficient as possible.

Zola, the radiator in the room with the room 'stat should NOT have a 'functioning' TRV on it; the TRV and the room 'stat will 'fight' and confuse eachother. Since you do have a TRV there, then - as said by others - you either open it up fully ('5'?) or even unscrew its head. That, tho', can lead to another issue, which you have already found - the hallway rad is a tad too powerful. There is a solution...

Background: The idea is that the room stat should be positioned in a room which is expected to have a pretty stable temp. The hall was traditionally used for this, and that's usually fine, but most folk wouldn't want their hallways to be at 20oC as this is a waste of energy (unless you tend to leave the doors open, so want it at the same temp as the rest of the downstairs).

So, assuming you'd rather have the hall at, say, 18oC and the adjacent sitting room at a more comfy 20oC, then you do need to set the wall 'stat to 18oC, because that is what controls the temp in the hallway. As you have found out, tho', this means that the hallway gets to 18 before the sitting room is as warm as you want. So the wall 'stat  in the hallway 'clicks' at 18oC, and this turns off the boiler before your S-R reaches the higher temp you want. Grrr. I mean, brrrr.

The solution is to turn down the hallway radiator so it outputs less heat - becomes a little less powerful - but you DON'T do this via the TRV, as the TRV will become 'active' again if you do, and automatically keep changing its setting depending on the room temp - ie, it'll start to confuse matters again. So what you actually want is a 'manual' control on that radiator, one that you tweak and leave, and that is what should be on the hallway rad. However, you have a TRV, and you are stuck with it! (Not worth the cost of swapping it).

Instead, then, you leave the TRV on 'max' (or headless) and go to the other end of the rad where you'll find a 'lockshield' valve. This will likely have a plastic cap on it, that just spins loosely, and can likely even be pulled off - if it has a screw in t'middle, then remove this first. Underneath you'll find a brass spindle with a flattened head, and this will allow you to turn this spindle using a spanner or similar.

DON'T TOUCH IT YET! The L/S should have been set to the correct position when the rad was installed, and - if so - then even small adjustments will have a noticeable effect on the rad's output. You want to know WHAT that setting is before you start turning it! So, get a wee paper flag and a bit of tape, and stick this to the spindle to act as a pointer. Now turn the spindle clockwise to close off that end fully, counting the number of whole and part-turns taken. It might only be a couple of turns, even less, but note it down - because the next thing is to go back to the starting position. Your rad should now be as 'powerful' as it was before.

Ok, you want that rad to be slightly less powerful. You want it to heat the hallway more slowly. You want to give the rest of the house more time to get up to temp, before the wall 'stat gets turned off. IF the L/S was around 2 turns from the fully closed position, then first try closing it a half-turn. Note this down. See how this works - is it enough, or does the hallway still get up to, say, the preferred 18oC too quickly? If it does, then close it a further half-turn.

You get the idea?

It's all relative; if the L/S was, say, 8 turns open (far too much - ie it was never 'balanced'), then clsoing it in half-turn steps ain't going to do anything until you get down closer to 2 turns open, so I would turn it down to 'two turns from closed', and then start the half-turn malarkey.

What you are doing is 'balancing' the system. You are telling that rad how powerful it should be for that room. Imagine fitting the same-sized rads in every room in the house, S-R, bedrooms, hallway, bathroom. Obviously, the small rooms would heat up far too quickly. Also, some rooms - say bedrooms - would be just get too hot, full stop. If you tackle the L/Ss of each, you can make the bedroom rads less powerful so they are suited to these rooms, leave the S-R rad fully powerful 'cos you want that large room to be warm, etc etc. Obviously it would be daft having all the rads the same size, but that just shows the principle of 'balancing'.

Once your rads have been balanced to make them the most suitable 'power' for each room, THEN you can turn them up and down at will using the other end - the manual valve or the TRV, whatever is fitted.

Sooooo, what you need to do - if the room 'stat is to remain in the hallway - is to turn down the hallway rad's 'power' output, as explained above. 

I'm guessing hallways were traditionally used as the preferred room stat location since the main living area would often have a secondary source of heat, such as an open fire. This is more often not the case any more. If you had the room 'stat in the S-R and also put a fire on in there, what would happen is that the S-R would heat up to the 'stat's setting quickly due to the rads AND the fire, and would become really cosy. BUT, this would then turn off the room 'stat, and the rest of the house would go cold! So, if you HAVE a secondary source of heat in your living area, then do not move the room 'stat there - leave it in the hallway, and tweak down it's L/S.

If you DON'T have a secondary source of heat in the living area, then - personally - that's where I'd move the wall 'stat. This is easy to do - I'll explain below. If you move the wall 'stat to the S-R, then you fully open/remove the TRV heads in there, and turn the hallway one to whatever temp you want in there, say between 2 and 3.

Your existing wall 'stat is likely an 'electro-mechanical' type - it uses a mechanical device to sense the room temp, but also adds a wee heater in there in order to make it less sluggish. To move this, the easiest way is to buy a WiFi room stat (and make it Programmable whilst you're at it...), and mount the receiver in the old 'stat's position - very easy to do (for a sparky or competent DIYer). You then bring the 'control' part into the S-R, ideally mounted to the wall, but it can sit on a unit (the lower it is mounted, the lower the set temp should be. Eg, for a cosy room, if it's sitting on a side board, then 19-20oC should be fine. If it's wall-mounted at the higher recommended ~1.5m, then it's likely you'd set it to 20-21oC. Both temps are actually the 'same' for these heights!)

Do you know what a Programmable 'Stat is? These will take care of the temp AND the time. Eg, you can set it to turn on the heating at, say 6amm at 20oC, go down to 18oC at 7.30am, back up to 21oC at 5pm... that sort of stuff. It'll almost certainly save you money. Lots of different makes, and many will also work via a phone App, so you can change/override it at will, even away from the home. You can pick up a near-new Hive for around £50 on t'Bay, or Facebook Marketplace. But there are many other makes.