Radiator question

ThisIsWeird

FreeBear said:

ThisIsWeird said: 2) turn the hallway rad down a small amount so that it outputs less, so takes longer to get the hallway up to 18oC. That way the sitting room rad will have more time to get the sitting room warmer. (This is the 'proper' tweak. But, the sitting room rads should really have TRVs on them).

A longer term "proper" solution is to install a larger radiator in the lounge and make sure all radiators have TRVs fitted.

Depending on the current flow temperature and exact make/model of the lockshields in the hallway, it may not be possible to dial that radiator back by much.

Well, yes, or you could replace all the rads, and the boiler, and...
The proper 'solution' to BF's situation, as it stands, is almost certainly to tweak down the hallway rad a tad, which can - again almost certainly - be done.
In addition, tho', I'd be looking to move the stat into the sitting room - the single and most efficient way to maintain the desired temp in that room.

Albermarle

Like JM, I assume that '17.8oC' refers to the room's temp, and not the rad's.

I must admit I thought he was talking about the radiator itself. Re reading the OP it is not clear either way . 

I'm trying to understand why my lounge radiator never goes above 17.8 degrees

LateStarter

Well...you set the thermostat in the hall to 18 degrees.

• the hall gets to 18 degrees
• at this point your lounge is at 17.8
• your thermostat (correctly) tells the boiler to stop

How do you expect the lounge to get hotter?

breaking_free

ThisIsWeird said:

Sounds like what junglist says. It's working normally, but it just needs tweaking.
Like JM, I assume that '17.8oC' refers to the room's temp, and not the rad's.
BreakingFree, a Q - when the sitting room rad initially comes on, is it 'hot' to the touch? If 'yes', then almost certainly there's nothing wrong, but you just need to tweak things.
The two tweaks you can do are:
1) turn the hallway room stat up a degree or more. (Drawback - the hallway will now become warmer than you may want, so a waste of energy.) Your sitting room should also become warmer as your boiler will be on for longer.
2) turn the hallway rad down a small amount so that it outputs less, so takes longer to get the hallway up to 18oC. That way the sitting room rad will have more time to get the sitting room warmer. (This is the 'proper' tweak. But, the sitting room rads should really have TRVs on them).
Better still, imv, is to move the hallway stat into the sitting room, almost certainly easier than you may fear. This is the best way to get the most important room in the house to exactly the temp you want, and every other room can be adjusted separately without affecting this. Show us your stat if you fancy doing this. Seriously, the best method. And, you can consider going 'Smart' at the same time. You will giggle with delight as you sit watching BBad, and control the room's temp with a touch of your phone. You will, you will...

Correctamundo - it's the room temp that is 17.8: sorry for the unclear explanation. And yes, the rad is very toasty to the touch.

Hmmm...I do like the idea of shifting the thermostat as then I can keep a proper eye on it too. Here tis. I've just gotten back home and switched it on, hence why the temp is so low. I'm going to set the thermostat to 19 so I can see what temp the lounge rad manages to output. It's gonna take a while from this low starting point...

ThisIsWeird

breaking_free said:

Correctamundo - it's the room temp that is 17.8: sorry for the unclear explanation. And yes, the rad is very toasty to the touch.

Hmmm...I do like the idea of shifting the thermostat as then I can keep a proper eye on it too. Here tis. I've just gotten back home and switched it on, hence why the temp is so low. I'm going to set the thermostat to 19 so I can see what temp the lounge rad manages to output. It's gonna take a while from this low starting point...

Thanks for the clarification. And - 11.7oC?! Brrrrrr :-)

Ok, the following may get a bit technical, so some deep breathing may be useful.

Pull that darned thing off the wall, and carry it into your sitting room.

Phew.

Jobbie jobbed.

Once it's in your sitting room, then the temp you dial up on that 'stat will be the temp then delivered to your sitting room.

Your hallway rad may need turning down a tad, if you find your hallway becomes too warm, or warmer than you like (usually, hallways are fine for 18oC or so.)

Look up that model of room 'stat, and see how to remove it, but it won't (shouldn't...) have any wires going to it, so it's 'click' to remove it off its backplate, unscrew that mounting plate, move it into the sitting room, and find a nice new home for it. You can simply remove that unit and stand it on a suitable surface to begin with - a sideboard or summat. Keep it away from nearby rads, and windows, and doors.

See how that goes :-)

ic

The thermostat you've pictured is the master on/off for your boiler.  So you've set it to 18 degrees - if the room it is in is less than 18 degrees, it asks the boiler to run.  When that room is up to 18 degrees it asks the boiler to stop heating (the whole house!).  Only when the hall drops below 18 does it ask for the boiler to come back on.  The loops over and over until its programmed to go off for the night.

The theory is the thermostat is located in the coldest room, which takes the longest to heat (hallway is normal, usually the location of a draughty front door which will be opened occasionally letting out the heat).  All other rads in the house have TRVs, which each control only the radiator they are connected to.  When a TRV senses the room is up to temp it turns off the single radiator - it cannot demand heat from the main boiler however.

As has been mentioned, it sounds like your living room radiator is too small - however as you've identified, its also blocked behind furniture which will reduce performance.  Try giving it more room "to breathe".  Otherwise you could look to have the system balanced (a simple but time consuming job adjusting the valves on the otherside of the radiator from the TRV - heating engineers rarely do this), or get a larger or additional rad installed in the living room.

I expect your thermostat is wired to the boiler, moving it will require either rewiring, or purchase of a new wireless thermostat.  However note as above, it will react to the room it is in, and command the boiler to run accordingly.

(Just to add, there are now "smart" TRVs available, which can demand heat from the boiler.  These are expensive and rarely pay for themselves, so I won't go into that here!)

FreeBear

ThisIsWeird said: Look up that model of room 'stat, and see how to remove it, but it won't (shouldn't...) have any wires going to it, so it's 'click' to remove it off its backplate, unscrew that mounting plate, move it into the sitting room, and find a nice new home for it.

There is a little recess at the bottom of the casing. Insert a flat bladed screwdriver, then twist/lever it off the backplate. Being battery operated, there are no wires in the backplate, so that bit can remain screwed to the wall.

ThisIsWeird

https://www.worcester-bosch.co.uk/products/boiler-controls/directory/greenstar-comfort-ii-rf-1

Remove using a screwdriver - one twist, Fig 7 - and take into sitting room. If that does the trick, then unscrew the mounting plate, and move that too

breaking_free

Great stuff all, I'll look at moving the thermostat tomorrow (busy today). Last night I turned the thermostat in the hall up a click and - who would have thought it - the lounge temperature got above 18   So that's one problem sorted. 

jvjack

Nice one.  Also thermometers don't always give exact temperature to each other. I have 4 and they are all 0.5 to1 degree below the thermostat one when put side by side.  Just a thought but 18 degrees behind that sofa would suggest in front of sofa temperature is lower. Maybe quite a bit. 
Edit: just to add . Found out my hall radiator can't be turned up or down.  Its a safety feature in case all other radiators are turned off and so allows hot water to flow.