TRV in conservatory

[2wd]

Hi
We have a large conservatory and I'm concerned that if a TRV is fitted to the radiator then especially in winter the room will never reach temperature and will just keep calling for heat and therefore boiler will just keep firing up.
Is this correct

 

[terryplumb]

Have you got a wall thermostat ,(often in the hall ) ?
Conservatorys loose quite a bit of heat ,whether you have a trv or a wheel head valve. The trv does not directly control the boiler ,but the wall stat does ( if you have one )

 

[2wd]

Hi
No I just have a digital room stat in the living room
TRVs in bedrooms and hallway
Had a TRV in conny but took it off as was concerned it would make boiler fire up constantly

 

[stem]

Most TRV's are just mechanical devices that open and close according to the temperature in which is is located. There is no electrical connection to the boiler. The room thermostat elsewhere controls the system.

If the room thermostat goes off, the heating will go, off regardless of the position of the TRV's

Having said that there are now systems that the TRV's are linked up to a central controller that does control the boiler such as Honeywell evohome. But standard TRV's don't.

I added a conservatory to my home 10 years ago, and was told by my local building control that I couldn't do what you propose, because the building regulations stipulate that conservatory heating must be independent from the main house with its own separate time and temperature control. Fitting a TRV to a radiator controlled by the main house controls didn't comply.

 

[2wd]

Many thanks

That would explain something else then.

We don't use the living room in the morning so I've recently turned down the room stat to 19 but turned up the TRVs in the rest of the house.
This morning was quite mild and therefore the heating didn't come on for very long,so the rooms where the TRVs are in were cool.

Not sure how to resolve that without heating the living room up which seems false economy

 

[Notch7]

because the building regulations stipulate that conservatory heating must be independent from the main house with its own separate time and temperature control. Fitting a TRV to a radiator controlled by the main house controls didn't comply.

I was told that by a building inspector.

However, I found online 'building inspector guidance notes' -which said TRV is acceptable as define a separate heating zone. The notes were more recent than 10 years ago though.

It was all paper pushing because the project in question was an orangery on a listed building -the house was really poorly insulated, single glazing, solid walls etc etc. And the inspector kept saying we needed a SAPS test

 

[stem]

Initially I was annoyed that I couldn't have a radiator in my conservatory, so ended up fitting electric heating with it's own programmable thermostat. Completely separate to the house. And in the end I felt it worked better. It will warm up very quickly when we go in and want it on, even if the rest of the house is already warm and the boiler is off. An added advantage is on a cool evening in spring / autumn we can warm the conservatory without having the rest of the house heating on.

We don't use the conservatory much in the winter, only at weekends really as it's dark in the week when we get home from work. So electricity is OK. I wouldn't want to heat it permanently that way though as it would cost more.

EDIT
A quick search turned up the latest info including 2018 amendments, and it still says in 4.8b that the conservatory should have independent temperature and on/off controls to the rest of the dwelling.

 

[2wd]

I use a portable calor gas heater as well in winter

Usually last 2-3 months the time we are in there so happy at around £10.00 per month for a cosy conservatory

 

[ianmcd]

I know what the regulations say about radiators in conservatory's, who is really going to know ?

 

[stem]

...In my case the building inspector that wouldn't sign it off. But that was because it was done at the same time as an extension. May be if it had been added later.....

 

[hard-work]

I added a conservatory to my home 10 years ago, and was told by my local building control that I couldn't do what you propose, because the building regulations stipulate that conservatory heating must be independent from the main house with its own separate time and temperature control. Fitting a TRV to a radiator controlled by the main house controls didn't comply.

A Myson fan heater does apply with a wall stat/timer. Myson's also heat up very fast, so ideal for conservatories.

 

[hard-work]

EDIT
A quick search turned up the latest info including 2018 amendments, and it still says in 4.8b that the conservatory should have independent temperature and on/off controls to the rest of the dwelling.

View attachment 153414

Independent on-off controls. No mention of timer. A Myson has on-off switches and a thermostat. A radiator can be fitted as long as it is fed via a zone valve.

 

[stem]

In most homes the on/off control is provided by a programmer / timeswitch. If you achieve on/off control another way that would comply, provided it was 'independent' from the main house.

In my case it was explained to me that as my installation stood:

"temperature control" = The Room Thermostat in the hall

"and on /off" control" = The Programmer in the Kitchen

I was also referred to the dictionary definition of independent.

As the programmer in the house would have been controlling the on / off times for the house, and also the conservatory it was not deemed to be independent. The conservatory was reliant on the main house heating also being 'on'.

A motorised valve controlling a separate heating zone for the conservatory, would seem to meet the requirement. I considered inserting a motorised valve in the pipework going to the conservatory radiator, but was told I couldn't unless I plumbed / wired a completely separate zone for it. Otherwise it wasn't 'independent' from the main house radiators as they still had to be on for the conservatory heating to be on. The amount of work involved in doing that put me off.

I was annoyed at the time, but in the long run the independent electric heating in our conservatory probably worked out better for us.

 

[hard-work]

I have the impression the BCO never understood it - not uncommon. There is no mention of independent timer control in the pic you posted, I have reposted it below. Only mentioning independent on-off and temp controls. On-off can be a manual switch. Reading it, a Myson, which has integrated temp and on-off control would do. Unless there are some other paragraphs that override that.

It is obvious they do not want the heating to be on in the conservatory all the time the main heating system is on. A Myson gives that control in that heat is not sent to the conservatory by throwing a switch. Switch it off and no heat - simple. It also stops the conservatory overheating with its thermostat.

 

[stem]

I don't disagree about the time switch.

In most homes the on/off control is provided by a programmer / timeswitch. If you achieve on/off control another way that would comply.

In my case the timeswitch was the on/off control so that was why I mentioned it.

To be independent I was told that the conservatory and house had to be errm.....independent ["the first one is not affected or influenced by the second"] so that:

1) The house heating can be 'on' without the conservatory heating being 'on' (Saves energy by not heating the conservatory when not being used)

2) The conservatory heating can be 'on' without the main house heating being on'. (Saves energy by not heating the house when you just want a bit or warmth in the conservatory on a chilly evening)

The whole thing was a nightmare really, apart from the heating issue we had to have external double glazed & seald doors installed between the conservatory and the kitchen, and the conservatory and dining room. Visitors regularly trip over the raised threshold as they don't expect them to be there.

Also our 'conservatory' has a glass roof and just one glass wall facing the garden (the others 3 walls are insulated cavity walls). Originally we had wanted to have a tiled roof with skylights, but were told that if we did so it would no longer be classed as a conservatory because it didn't have enough glass and wouldn't be exempt from planning permission. But if we were to apply for planning permission as a regular extension, we wouldn't get it because it would have too much glass.

So, it would be OK to have more glass than we wanted, or less glass than we wanted...but not something in between which was what we actually wanted.

As I'm not responsible for making the rules or enforcing them, I just have to do as I'm told by the powers that be.