My heating thermostat is in the wrong place!

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Hi all

I have a Honeywell CM507 central heating theromostat: https://m.productcatalog.honeywellhome.com/hungary/pdf/en0h8550uk07r1205.pdf

Its on my very small landing next to a radiator. My large bedroom is on the other side of the landing and needs to be kept at 21c. As the hetaing comes on and off based on the temprature on the landing (which can increase/decrease very quickly) this is not ideal.

Ideally the stat should have been in my bedroom.

Is there a solution to this other than moving all the wiring which would be a huge job? Can I buy a 'mobile' thermostat to keep in my room and if so how would this talk to the base station?
 
Soldato
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You can buy almost any compatible wireless thermostat. It might sound like boilers are crazy technology that only gas engineers can touch but this isn't true.

The pcb of a boiler is just a simple circuit board. The thermostat is wired with simple wire (in most cases) to two points on the pcb connection..

A remote thermostat that you will buy will need 4 wires. 1 power 2 neutral 3 on 4 off
Wire the receiver to the pcb and place it above the boiler and that's about it. (and when I say wire, it's literally shoving the wiring under the screw)

I did it, it's not hard.
 
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Hi all

I have a Honeywell CM507 central heating theromostat: https://m.productcatalog.honeywellhome.com/hungary/pdf/en0h8550uk07r1205.pdf

Its on my very small landing next to a radiator. My large bedroom is on the other side of the landing and needs to be kept at 21c. As the hetaing comes on and off based on the temprature on the landing (which can increase/decrease very quickly) this is not ideal.

Ideally the stat should have been in my bedroom.

Is there a solution to this other than moving all the wiring which would be a huge job? Can I buy a 'mobile' thermostat to keep in my room and if so how would this talk to the base station?

That's the correct location - not in a room and near a radiator that does not have a thermostatic valve. This sets the overall system temp. You then use thermostatic valves in all the other rooms to match the system temp or set that room cooler (bedrooms are normally around 18c. I actually prefer 15c but as the house is so well insulated it doesn't get down that far despite the CH switching off at 21:00).
 
Soldato
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That's the correct location - not in a room and near a radiator that does not have a thermostatic valve. This sets the overall system temp. You then use thermostatic valves in all the other rooms to match the system temp or set that room cooler (bedrooms are normally around 18c. I actually prefer 15c but as the house is so well insulated it doesn't get down that far despite the CH switching off at 21:00).

But if his bedroom thermostatic is on full and the rad in the hallway heats up a small space to quickly. Doesn't matter if his main bedroom rad is on full blast, it's not getting hot enough in the room before the stat shuts the heating off.
 
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I have my remote stat in my front room because it takes the longest to get to the target temperature.

Also you shouldn't have thermostatic valves on every radiator I read, because if there's a call for heat and all the valves are off the heat has nowhere to go.
 
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I have my remote stat in my front room because it takes the longest to get to the target temperature.

Also you shouldn't have thermostatic valves on every radiator I read, because if there's a call for heat and all the valves are off the heat has nowhere to go.

The only radiator that doesn't need a thermostatic valve is the rad nearest the thermostat. If you don't have a remote thermostat system it's fine to have a thermostatic valve on every rad as CH systems are parallel, not sequential*

As for your front room taking the longest to warm up, see the link I posted above - sounds like you need to balance your system.

*unless you have a really old system from the 70s, but these are very rare now.
 
Caporegime
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The only radiator that doesn't need a thermostatic valve is the rad nearest the thermostat. If you don't have a remote thermostat system it's fine to have a thermostatic valve on every rad as CH systems are parallel, not sequential*

As for your front room taking the longest to warm up, see the link I posted above - sounds like you need to balance your system.

*unless you have a really old system from the 70s, but these are very rare now.
Its nothing to do with balancing, my front room is very large compared to the rest if the rooms and there is open air underneath it as the cars drive under it to get to the carpark behind.
 

JRJ

JRJ

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Go for a Hive/Tado or similar smart system that has digital TRV's which are able to call for demand from the boiler independent of the main stat.
 
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Regardless of where your room stat is located, the radiators should be balanced so that they all heat up evenly. If the rads are sized correctly to the rooms they are in, the rooms should also heat up evenly. If you prefer some rooms to remain cooler, you can adjust the TRVs down.

The room/hallway/landing with the room stat should NOT have a TRV as this will conflict with the stat. I.e. the TRV will start to close before the stat reaches it's temperature.

The problem is how quickly rooms cool down. Depending on the insulation level and number of external walls, some rooms will cool down much faster than others. If you put the room stat in the coldest room, the others will overheat. The only way to solve this is to a) increase the insulation, b) add smart TRV's so each room can be heated independently.
 
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That's exactly the reason behind balancing a CH system.
You don't know what you're talking about, I have sensors logging data now, this is with the stat in the living room, radiators with no TRV in living room and bathroom.
Yes bathroom gets overly warm, but it needs to be when you're trying to dry it out after a shower.

If you have TRVs on all your radiators you need a bypass of some description, I know the system is parallel but its not good to dump most of the heat back to the boiler if all rads are off.


 
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You don't know what you're talking about

I trained as a plumber when I left school. I know what I'm talking about.

Just to make it really simple. You balance all the rads (with the trvs open at max) so all the rooms heat up at the same rate to achieve whatever the stat is set to. Then you adjust each individual room/area downwards using the trvs if you want them cooler.

At least you have no trvs in the room with the thermostat, but it's unconventional to have it in the living room. The usual place is the hallway.
 
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Right well mine works as it is so go bother someone else with your 'knowledge'.

It works because of a bodge. It's like hanging kitchen wall units with no more nails.

As for bothering someone else, you were the one posting incorrect info so don't have a girly hissy fit if you get called out on it.

Remember this gem?

Also you shouldn't have thermostatic valves on every radiator I read, because if there's a call for heat and all the valves are off the heat has nowhere to go.

:D:D:D:D:D:D:D:D
 
Caporegime
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Because if the boiler ends up running, with all the rads off (TRVs closed) where is the heat going to go? That's right, back to the boiler. Combi boilers have a MINIMUM flow rate.

I never suggested a heating system was in series, I know its a parellel circuit with branches to the radiators.

You openly admitted you're not a professional, so I'll take any advice you post with a tub of salt.
 
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