CH Thermostats in hallway - why?
Discussion
It's set on a timer to be at 19 degrees when we are in the house but not in bed then 17 degrees when out of the house or in bed.
So, the house never really feels cold at all. I've lowered the night time temp to 15 so that gives a wider spread of work for the boiler to do between modes. I'll see if we notice anything in either the way the house feels, and on the gas bills.
So, the house never really feels cold at all. I've lowered the night time temp to 15 so that gives a wider spread of work for the boiler to do between modes. I'll see if we notice anything in either the way the house feels, and on the gas bills.
Thats a crazy place to put the thermostat. Right ontop of a rad. Just means it turns the boiler off when the warm flow of air is saying at set-point, not an approximation of the house!
Also, another one which I had an argument with my builder about, and possibly why you think TRVs are crap - they're meant to be mounted horizontally to get them out of the convection current of the hot air coming off the pipes, meaning again they don't cycle too quickly, and give a better approximation of the room temp.
We have a Tado, and they recommend you put the stat in the most used room to use less gas (the theory being, why use the hallway, when you don't sit in it very often. But currently finding that it means the rest of the house is quite cold. But then I'm not convinced that swapping it around isn't going to cause the opposite problem.
Might swap to TRVs in the lounge and none on the hallway rad, and then put it back out there, use a lower set point temp and see how we get on.
Also, another one which I had an argument with my builder about, and possibly why you think TRVs are crap - they're meant to be mounted horizontally to get them out of the convection current of the hot air coming off the pipes, meaning again they don't cycle too quickly, and give a better approximation of the room temp.
We have a Tado, and they recommend you put the stat in the most used room to use less gas (the theory being, why use the hallway, when you don't sit in it very often. But currently finding that it means the rest of the house is quite cold. But then I'm not convinced that swapping it around isn't going to cause the opposite problem.
Might swap to TRVs in the lounge and none on the hallway rad, and then put it back out there, use a lower set point temp and see how we get on.
Pheo said:
.. B ut currently finding that it means the rest of the house is quite cold. But then I'm not convinced that swapping it around isn't going to cause the opposite problem.
Might swap to TRVs in the lounge and none on the hallway rad, and then put it back out there, use a lower set point temp and see how we get on.
That the issue. Stat is now in the main family room which will stay warm while the rest of the house cools down. The kids are in bed so let's see if they wake up complaining. Might swap to TRVs in the lounge and none on the hallway rad, and then put it back out there, use a lower set point temp and see how we get on.
Previously, the hall would take much longer to warm up meaning the whole house has hot water to the rads with the room temps controlled by TRV. This option will obviously use more gas though.
I think the reason I put the Stat above the rad was to minimise the time the boiler fired for, thus saving gas..... Fook knows anyway, I've confused myself now, what was the question again..?
Yes, I should have written, "Dragging this thread back to life again".
Wasn't until after I posted I realised it was a 2011 thread.
Oops.
I found the page when Googling sites with explanations why room stats shouldn't be in the same locations as TRV's to prove to my electrician that he was wrong.
His opinion is that a wireless stat can go anywhere, most of the time he just gives the wireless stat to his customer telling them to put it wherever they like.
He thinks that's why they're wireless, to be carried around the house room to room.
Wtf?!?
I argued that's not good practice, the customer isn't a heating engineer, they don't know where the best place is. The customer could put it in the kitchen, or above a radiator, or in a room with a TRV, or in direct sunlight, or even in the fridge to save wall space!
RANDOM
Twice.
Wasn't until after I posted I realised it was a 2011 thread.
Oops.
I found the page when Googling sites with explanations why room stats shouldn't be in the same locations as TRV's to prove to my electrician that he was wrong.
His opinion is that a wireless stat can go anywhere, most of the time he just gives the wireless stat to his customer telling them to put it wherever they like.
He thinks that's why they're wireless, to be carried around the house room to room.
Wtf?!?
I argued that's not good practice, the customer isn't a heating engineer, they don't know where the best place is. The customer could put it in the kitchen, or above a radiator, or in a room with a TRV, or in direct sunlight, or even in the fridge to save wall space!
RANDOM
Twice.
Edited by GMLeo on Monday 2nd March 06:24
Thank you all so much for contributing to this thread. After reading through everyone's comments, and having a good think about the situation I think that i understand the interaction between the thermostat and TRV's and the boiler properly now. I will try and resume things clearly for anyone who is interested!
A) Thermostats switch the boiler on and off (according the the room temp and user set temp)
B) TRVs limit the temperature, and cannot increase the temperature.
C) If all the TRVs are closed, and the boiler is trying to pump out hot water to all the radiators, this is not good (I'll leave the real heating engineers to get into the detail.)
1. On the subject of a TRV in the same room as a thermostat:
If the thermostat is set to 20deg and the TRV in the same room limits to 18deg, then the boiler/thermostat will constantly be on.
If the room temp is 18 deg, thermostat will be on until the room is at 20deg, ie never!
No point having a thermostat at all. The boiler is constantly on.
If the thermostat is set to 20deg and the TRV in the same room is set to 22deg, the boiler will switch on and off as necessary to maintain 20deg in the room, the TRV will never be triggered (as we never reach 22deg) and is useless, but not harmful.
If the thermostat and TRV are set to exactly the same temperature, then due to minor variations in the precision of these instruments sometimes the TRV will kick in and sometimes the thermostat will kick in and the setup will be a mess.
SO: useless, but not harmful to have a TRV in the same room as the thermostat, as long as it is set well above the set temp of the thermostat.
2. Where to put the thermostat?
Imagine that I have three rooms, the room temperatures that I'd like...
the front room 19deg, this room houses the thermostat.
the kitchen 20deg
the bedroom 16deg
I set the front room with thermostat to 19 deg. This room will always be around 19 deg, perfect!
The boiler switches on and off to maintain this temperature. When the boiler is on, the other rooms are also heated, when it is off, they are not.
The bedroom will be great, the TRV on the radiator is set to limit at 16 deg, as this is much lower than the front room with thermostat, the cycling on and off of the boiler should easily be able to maintain this temperature, and if ever it starts to go higher, the TRV will cut the hot water.
The kitchen is a different matter, it is set hotter than the front room. Several factors will come into play, size of the radiators, set temp of the boiler, insulation and exposure/heat loss from the kitchen, drafts, whether or not doors are opened and how often, if the oven is on etc etc. The kitchen will never get hotter than 20 deg because of the radiator, (although using the oven could raise the temperature!) However it could remain colder than 20deg, because the kitchen will only be heated IF the front room is also being heated!!!
The temperature set in the front room is 19deg, when it cools to 18.9 deg, the boiler and heating will kick in and warm up the room, when it hits 19,0 deg it will switch off, but it will inevitably overshoot a little to say 19,4deg, the front room temperature will oscillate up and down by a small amount around the set point, with the boiler being on and off alternately. The thermostat doesn't care about the too hot or too cold kitchen. This is just how a thermostat works!
So, if the kitchen is exactly the same as the front room in terms of all the variables, (radiator size, insulation and heat loss, and eventually drafts and other sources of heat) it will actually be 19deg in the kitchen and not the 20deg that I would like.... Hmm what a pickle!
However, if the kitchen is better insulated, or has a bigger radiator, it will be able to stock up heat more effectively than the front room, and will heat up more than the front room during the time which the boiler is on and pumping hot water to all the radiators (or lose less heat when the boiler is off). Of course the TRV on the kitchen radiator will stop it going too far, and it will never go above 20deg.
If the kitchen is insulated equally or less than the front room then what can we do? Well lets say (as in the case of my house) that the front door opens into the front room. Well every time the front door is opened, heat will escape, the room will cool, and the thermostat will signal to the boiler to kick in. The kitchen has not been cooled and can use this moment to increase the temperature in the kitchen to 20 deg, while the front room tries to get back up to 19 deg...YAY!
SO it seems to me that the best place to put the thermostat, is the room which will need to be heated the most frequently, or the room which loses heat the most easily. This thermostat room really needs the boiler to kick in and maintain temperature the most often, the other rooms which lose heat more slowly will have more headroom and time to heat with this on off cycling of the boiler. No room will ever exceed the desired temperature thanks to our TRVs, and we would expect that all the rooms should be hot enough because they are less needy of frequent heating than the room with the thermostat.
Which room in your house loses the most heat... is it the hallway, with people going in and out of the front door?
Alternatively, if you really want one room much hotter than all the others, put the thermostat here, the heating will be on a lot to keep it hot, also because it is so hot it will lose heat more quickly, and the other rooms will just be limited by their TRVs.
I have no particular plumbing experience, but I like understanding things, and I fell on this thread as I was trying to work out how to best adjust the heating in my house. Working through this logic problem was fun and useful, and maybe after a google search someone will fall on this thread, and if they read to then end will hopefully find my words useful.
If anyone disagrees with me PLEASE say so, I love learning stuff, so being corrected is a good thing!
Background: My kitchen has loads of windows and no room above. Badly insulated by its very nature. It has a huge radiator (with a TRV missing the headpiece, ie always open on max) but often in the morning it is around 15-16deg in the kitchen (house thermostat set to 18deg at night 19 during the day). I nearly bought a radiant heater for the kitchen but my wife said no! All of a sudden a few weeks ago, it was suddenly heating to 24-25 deg, the front room temperature (with thermostat) was fine. It was a pleasant change for a few days, but such a temperature differential became awful. I thought that I'd better try and understand what was happening. At first I thought that the TRV valve had been stuck for the past few years since we bought the house, and had suddenly become unstuck. Today I looked at the TRV in the front room near to the thermostat, it was set at 1! So basically I think that my central heating has been trying to heat the front room, but been blocked by the TRV being set so low, the thermostat is sensing cold and the boiler must be on nearly all the time, and thus has been heating up the kitchen like a madman (with its TRV fully open)... what a goddamn mess! Even our bedrooms where a little too hot, 19-20deg instead of 18. It all seems to make sense now.
I have fully opened the TRV in the front room (today!), and am buying a TRV head to fit in the kitchen. And I have learned a lot in the process, writing all this down will help fix it in my head, and maybe help you?
Resurrect this thread for those in need of help!! Like me this morning!
A) Thermostats switch the boiler on and off (according the the room temp and user set temp)
B) TRVs limit the temperature, and cannot increase the temperature.
C) If all the TRVs are closed, and the boiler is trying to pump out hot water to all the radiators, this is not good (I'll leave the real heating engineers to get into the detail.)
1. On the subject of a TRV in the same room as a thermostat:
If the thermostat is set to 20deg and the TRV in the same room limits to 18deg, then the boiler/thermostat will constantly be on.
If the room temp is 18 deg, thermostat will be on until the room is at 20deg, ie never!
No point having a thermostat at all. The boiler is constantly on.
If the thermostat is set to 20deg and the TRV in the same room is set to 22deg, the boiler will switch on and off as necessary to maintain 20deg in the room, the TRV will never be triggered (as we never reach 22deg) and is useless, but not harmful.
If the thermostat and TRV are set to exactly the same temperature, then due to minor variations in the precision of these instruments sometimes the TRV will kick in and sometimes the thermostat will kick in and the setup will be a mess.
SO: useless, but not harmful to have a TRV in the same room as the thermostat, as long as it is set well above the set temp of the thermostat.
2. Where to put the thermostat?
Imagine that I have three rooms, the room temperatures that I'd like...
the front room 19deg, this room houses the thermostat.
the kitchen 20deg
the bedroom 16deg
I set the front room with thermostat to 19 deg. This room will always be around 19 deg, perfect!
The boiler switches on and off to maintain this temperature. When the boiler is on, the other rooms are also heated, when it is off, they are not.
The bedroom will be great, the TRV on the radiator is set to limit at 16 deg, as this is much lower than the front room with thermostat, the cycling on and off of the boiler should easily be able to maintain this temperature, and if ever it starts to go higher, the TRV will cut the hot water.
The kitchen is a different matter, it is set hotter than the front room. Several factors will come into play, size of the radiators, set temp of the boiler, insulation and exposure/heat loss from the kitchen, drafts, whether or not doors are opened and how often, if the oven is on etc etc. The kitchen will never get hotter than 20 deg because of the radiator, (although using the oven could raise the temperature!) However it could remain colder than 20deg, because the kitchen will only be heated IF the front room is also being heated!!!
The temperature set in the front room is 19deg, when it cools to 18.9 deg, the boiler and heating will kick in and warm up the room, when it hits 19,0 deg it will switch off, but it will inevitably overshoot a little to say 19,4deg, the front room temperature will oscillate up and down by a small amount around the set point, with the boiler being on and off alternately. The thermostat doesn't care about the too hot or too cold kitchen. This is just how a thermostat works!
So, if the kitchen is exactly the same as the front room in terms of all the variables, (radiator size, insulation and heat loss, and eventually drafts and other sources of heat) it will actually be 19deg in the kitchen and not the 20deg that I would like.... Hmm what a pickle!
However, if the kitchen is better insulated, or has a bigger radiator, it will be able to stock up heat more effectively than the front room, and will heat up more than the front room during the time which the boiler is on and pumping hot water to all the radiators (or lose less heat when the boiler is off). Of course the TRV on the kitchen radiator will stop it going too far, and it will never go above 20deg.
If the kitchen is insulated equally or less than the front room then what can we do? Well lets say (as in the case of my house) that the front door opens into the front room. Well every time the front door is opened, heat will escape, the room will cool, and the thermostat will signal to the boiler to kick in. The kitchen has not been cooled and can use this moment to increase the temperature in the kitchen to 20 deg, while the front room tries to get back up to 19 deg...YAY!
SO it seems to me that the best place to put the thermostat, is the room which will need to be heated the most frequently, or the room which loses heat the most easily. This thermostat room really needs the boiler to kick in and maintain temperature the most often, the other rooms which lose heat more slowly will have more headroom and time to heat with this on off cycling of the boiler. No room will ever exceed the desired temperature thanks to our TRVs, and we would expect that all the rooms should be hot enough because they are less needy of frequent heating than the room with the thermostat.
Which room in your house loses the most heat... is it the hallway, with people going in and out of the front door?
Alternatively, if you really want one room much hotter than all the others, put the thermostat here, the heating will be on a lot to keep it hot, also because it is so hot it will lose heat more quickly, and the other rooms will just be limited by their TRVs.
I have no particular plumbing experience, but I like understanding things, and I fell on this thread as I was trying to work out how to best adjust the heating in my house. Working through this logic problem was fun and useful, and maybe after a google search someone will fall on this thread, and if they read to then end will hopefully find my words useful.
If anyone disagrees with me PLEASE say so, I love learning stuff, so being corrected is a good thing!
Background: My kitchen has loads of windows and no room above. Badly insulated by its very nature. It has a huge radiator (with a TRV missing the headpiece, ie always open on max) but often in the morning it is around 15-16deg in the kitchen (house thermostat set to 18deg at night 19 during the day). I nearly bought a radiant heater for the kitchen but my wife said no! All of a sudden a few weeks ago, it was suddenly heating to 24-25 deg, the front room temperature (with thermostat) was fine. It was a pleasant change for a few days, but such a temperature differential became awful. I thought that I'd better try and understand what was happening. At first I thought that the TRV valve had been stuck for the past few years since we bought the house, and had suddenly become unstuck. Today I looked at the TRV in the front room near to the thermostat, it was set at 1! So basically I think that my central heating has been trying to heat the front room, but been blocked by the TRV being set so low, the thermostat is sensing cold and the boiler must be on nearly all the time, and thus has been heating up the kitchen like a madman (with its TRV fully open)... what a goddamn mess! Even our bedrooms where a little too hot, 19-20deg instead of 18. It all seems to make sense now.
I have fully opened the TRV in the front room (today!), and am buying a TRV head to fit in the kitchen. And I have learned a lot in the process, writing all this down will help fix it in my head, and maybe help you?
Resurrect this thread for those in need of help!! Like me this morning!
In the sixties my parents has gas c/ heating installed and the thermostat was in the hall of the bungalow which had little insulation and single glazed windows.
My Dad relocated the stat to the lounge which was heated by a gas fire and put it about 6' up the wall.
He was tighter than a ducks ****. The heating never went on with the stat set at what should have been a comfortable temparature.
I am lucky in my 60's to be able and willing to have the central heating on at a decent temparature, as well as an AGA and a log burner, I hate being cold!
My Dad relocated the stat to the lounge which was heated by a gas fire and put it about 6' up the wall.
He was tighter than a ducks ****. The heating never went on with the stat set at what should have been a comfortable temparature.
I am lucky in my 60's to be able and willing to have the central heating on at a decent temparature, as well as an AGA and a log burner, I hate being cold!
Hell of a thread resurrection!
The thermostat wants to be somewhere that is a good indication of the house temperature, not subject to extremesm accessable.
- Not directly above any rads, or in direct sunlight
- Not in a room without a rad, or with a trv thats going to be turned down.
- Not right by the front door, or the oven!
Living rooms can work, as long as they are not over radiatored as a lot are.
Hall ways can be ok, as long as it's away from the front door and or kitchen.
Landings are pretty good as long as you don't mind going upstairs to adjust.
If you have an open fire or stove, that is another consideration against livingroom.
We have ours on a shelf half way up the stairs, well around the corner from the front door.
Daniel
The thermostat wants to be somewhere that is a good indication of the house temperature, not subject to extremesm accessable.
- Not directly above any rads, or in direct sunlight
- Not in a room without a rad, or with a trv thats going to be turned down.
- Not right by the front door, or the oven!
Living rooms can work, as long as they are not over radiatored as a lot are.
Hall ways can be ok, as long as it's away from the front door and or kitchen.
Landings are pretty good as long as you don't mind going upstairs to adjust.
If you have an open fire or stove, that is another consideration against livingroom.
We have ours on a shelf half way up the stairs, well around the corner from the front door.
Daniel
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