Search the forum,

Discuss should i have a room thermostat with my combi boiler. in the Plumbing Jobs | The Job-board area at PlumbersForums.net

Status
Not open for further replies.
Have you checked if he`s even GSR?
Not being funny but most clients or customers take a firm or trsdesmsn on trust as we do with a client or customer ?
I have ripped multi million pound houses to bits yet never have I been asked to see any insurances or even proof of a qualification ?
Only job I had to prove insurance was on a job for the railways before network rail took over we even had to do a trackside test even though we were well away from tracks my blokes will never use a train again as all worried if trains were where we were working no way are they safe !
 
It is not air.
Sounds like your house is quite warm and the valves are closing themselves down or the valve heads are badly positioned. You may be used to the house being warmer so 20º may feel cold.

Have a read of this which explains a bit about how they work.
http://heating.danfoss.co.uk/PCMPDF/TRV_User-guide_Flyer_100x210mm_VUIDD102_2013_low-res.pdf
Getting The Best From Your TRVs

and get them to fit a room stat.
I only had two storage heaters that worked so my house was always cold, now its up to 19 at the moment. What i expected to get from GSH was that if it got too warm then i would be able to turn the heating down slightly without the rads going almost cold but because i dont have a room thermostat im have to go round the house adjusting each heater, but because they all go too cold when i turn them down i then have to turn them all up again, its keeping me fit anyway. I will get used to it i suppose.
 
controls to ensure that the boiler does not fire when there is no demand for heat.

so for example a trv may control a rad but has no control over the system, but a room stat and time control does.
 
Last edited:
controls to ensure that the boiler does not fire when there is no demand for heat.

so for example a trv may control a rad but has no control over the system, but a room stat and time control does.
ok thanks, i understand that now.
 
So would i be able to control the heat i want in my house better if i had a room thermostat.

The room thermostat will ensure that the boiler doesn't keep running when the temperature rises but fine control should be with the TRVs.

It doesn't sound to me like the operation of your system has been very well explained to you. A TRV does not vary the temperature of the water in the radiator. Think of it like an off switch that turns the radiator off when the room reaches a certain temperature. When the temperature drops below that temperature the valve opens and the radiator will get hot again.

It normally takes a little while to get the system set up as you want it but don't keep turning TRVs up and down as this defeating the object of having them. I generally set them to 1 or 2 in bedroom areas, 4 in living areas and 5 in bathrooms and advise the customer to tweak them over a period until they get the temperature they desire.
 
It's been inthe regs since 2002, so it must be already included in his quote :)

For umpteen years, good heating engineers have been fitting roomstats to control heating systems.

Each room has a design temperature. Living room 20 degrees C, hall 18, bedroom 16 and bathroom 25. Heat loss is calculated with these temperatures. Therefore a radiator fitted in the lounge will maintain lounge temperature at 20 when external temperature is at -1. It follows that a roomstat fitted in the hall and set to 18, will switch the boiler off when the hall reaches 18 degrees. By this time, the lounge will be at 20, bathroom at 25 and bedrooms at 16. Same roomstat if fitted in the lounge would be set to 20.

While a roomstat will shut a boiler down (conserving fuel), TRVs will stop taking heated water but fail to tell the boiler that it should stop. Meanwhile, the boiler has now to rely on its own stat to shut down. It keeps firing every so often to maintain the set boiler temperature.

If the TRVs are used alongside a roomstat, rooms that are naturaly warmer (say south facing), shut down by the TRV. Colder rooms continue to heat until the roomstat (hopefully fitted in one of these rooms) switches off the boiler.

If the radiators are oversized, guestimated or not balanced, the roomstat will get erroneous readings and by unable to function correctly.

Invite your engineer to carry out heat loss for the rooms and see if he is able to do that, if not choose someone else..

Modern digital roomstats can control room temerature to plus minus 0.5 degree
 
It's been inthe regs since 2002, so it must be already included in his quote :)

For umpteen years, good heating engineers have been fitting roomstats to control heating systems.

Each room has a design temperature. Living room 20 degrees C, hall 18, bedroom 16 and bathroom 25. Heat loss is calculated with these temperatures. Therefore a radiator fitted in the lounge will maintain lounge temperature at 20 when external temperature is at -1. It follows that a roomstat fitted in the hall and set to 18, will switch the boiler off when the hall reaches 18 degrees. By this time, the lounge will be at 20, bathroom at 25 and bedrooms at 16. Same roomstat if fitted in the lounge would be set to 20.

While a roomstat will shut a boiler down (conserving fuel), TRVs will stop taking heated water but fail to tell the boiler that it should stop. Meanwhile, the boiler has now to rely on its own stat to shut down. It keeps firing every so often to maintain the set boiler temperature.

If the TRVs are used alongside a roomstat, rooms that are naturaly warmer (say south facing), shut down by the TRV. Colder rooms continue to heat until the roomstat (hopefully fitted in one of these rooms) switches off the boiler.

If the radiators are oversized, guestimated or not balanced, the roomstat will get erroneous readings and by unable to function correctly.

Invite your engineer to carry out heat loss for the rooms and see if he is able to do that, if not choose someone else..

Modern digital roomstats can control room temerature to plus minus 0.5 degree

This is exactly how i thought it worked and sort of how i tried to explain it to my plumber but he said that the room i have the roomstat in will turn all the heating off when it may be needed in another room.
I see now that its about getting the balance right. I will get someone to fit one because i expect it will save me money too if the boiler is not firing all the time.
 
your plumber doesnt know what he is talking about. and to be frank i would ask to see what qualifications he has to have the right to call himself a plumber because he is giving you very bad advice. as said already a thermostat is needed to comply withbuilding regs.

why not post up in the looking for an engineer section. there may be one of us nearby who wil give you better advice.

Also get onto the GSR who fitted and hassle him for the cert and check the benchmark section has been filled at the back of the boiler manual/instructions.
 
your boiler requires interlock between its controls to operate efficiently and meet the building regulations. the cost of a room stat will be saved on your bill within one year, two at most. £15 for a stat, £5-£10 for cable and consumables, an extra hour or so in labour time if hes competent to fit one.
Ive checked the manual book that he has filled in and he has ticked the box...boiler interlock.. so does that mean he is saying that he has installed a room stat and not just the thermostatic valves on rads?
 
Here's the Good Practice Guide :

[DLMURL]http://www.draytoncontrols.co.uk/uploadedFiles/Drayton/Industry_Regulation/Good_Practise_Guide_302_ENG.pdf[/DLMURL]

Check out the top of page 8.

n.b. don't put / remove any trvs on the radiator(s) in the same room (or hall) that the room thermostat is.
 
Last edited by a moderator:
Ive checked the manual book that he has filled in and he has ticked the box...boiler interlock.. so does that mean he is saying that he has installed a room stat and not just the thermostatic valves on rads?

I would say yes, is it signed Mickey Mouse at the bottom as well?
 
Here's the Good Practice Guide :

[DLMURL]http://www.draytoncontrols.co.uk/uploadedFiles/Drayton/Industry_Regulation/Good_Practise_Guide_302_ENG.pdf[/DLMURL]

Check out the top of page 8.

n.b. don't put / remove any trvs on the radiator(s) in the same room (or hall) that the room thermostat is.

Nice guide! It's a few days old looking at the energy saving trust logo?
 
Last edited by a moderator:
Thanks guys but you havent really answered my question on the boiler interlock. When you GSE guys tick the box where it says boiler interlock provided what are you saying you have supplied or done.
 
Installed a stat and programmer or a programmable stat. Page 8 of the guide
 
An interlock is an arrangement of controls that stops the boiler firing when there is no demand for heat ie when the house has warmed up.
Std trv's only do not fulfill this requirement as they could all be shut off and the boiler will still operate heating water in a loop of pipe.
A room stat does because it shuts the boiler off until the room cools down.
 
WHen he has ticked that box he is saying that it has one and it is activated.

They danger here is that this person may be lying / being fraudulent. hence the links to the guides and building regs.

If he hasn't installed a room thermostat it is almost 100% certain that he hasn't actually done anything about the boiler interlock and just ticked the box.
In which case he is in breach of the building regulations.
He should also issue with a building regulations certificate. - Have you had one?

Have you got a room thermostat?
Have you got programmable trv's with a central controller? (or are they just 'twist the top' type)
 
Last edited:
WHen he has ticked that box he is saying that it has one and it is activated.

They danger here is that this person may be lying / being fraudulent. hence the links to the guides and building regs.

If he hasn't installed a room thermostat it is almost 100% certain that he hasn't actually done anything about the boiler interlock and just ticked the box.
In which case he is in breach of the building regulations.
He should also issue with a building regulations certificate. - Have you had one?

Have you got a room thermostat?
Have you got programmable trv's with a central controller? (or are they just 'twist the top' type)
They are just twist knob ones as far as i know. i dont have a room thermostat because the plumber said i didnt need but but his mate the GSE who connected me said i did but he still ticked the box knowing i didnt have one.The only paperwork he has left me is the commissioning check list.
 
So the boiler was installed by a non qualified engineer and signed off by another ? I would be calling gas safe!!
 
So the boiler was installed by a non qualified engineer and signed off by another ? I would be calling gas safe!!
Basically yes, the GSE did soldered the gas pipes and connect me but only because i told the plumber that he couldnt do it although he said he was competent. When i got his quote he told me that he got a GSE in to do the boiler but half way though the job he changed his mind.

I know ive done wrong so dont all have a go at me please, i dont have any backup so thats why im asking you guys for all the info because if i try and question my plumber he just makes me look a fool. The problem is ive known him and his entire family for years.
 
You now know what your system should have and how it should be configured.

Tell the plumber that you need it done in accordance with the building regs.

If between then they wont, then report to Gas Safe, Building Control, and your local Citizens Advice Bureau, as they shouldn't be allowed to continue this bad practice.

Just dowload the document on this link TACMA launches its guide to the new 2010 Part L Regulations - BEAMA | News
print it out and show it to them....
document summary
 
Last edited:
You now know what your system should have and how it should be configured.

Tell the plumber that you need it done in accordance with the building regs.

If between then they wont, then report to Gas Safe, Building Control, and your local Citizens Advice Bureau, as they shouldn't be allowed to continue this bad practice.

Just dowload the document on this link TACMA launches its guide to the new 2010 Part L Regulations - BEAMA | News
print it out and show it to them....
document summary
He will charge me for the room stat because it wasnt in the quote, i just thought that i was getting everything that was needed. I rang the guy who connected the gas today and asked him why he had ticked the box that said boiler interlock provided, he said that its nothing to do with having a room stat and that it just means that you can turn the boiler off manually.
 
He will charge me for the room stat because it wasnt in the quote, i just thought that i was getting everything that was needed. I rang the guy who connected the gas today and asked him why he had ticked the box that said boiler interlock provided, he said that its nothing to do with having a room stat and that it just means that you can turn the boiler off manually.
He really knows his stuff then !!!!!!!!
 
I rang the guy who connected the gas today and asked him why he had ticked the box that said boiler interlock provided, he said that its nothing to do with having a room stat and that it just means that you can turn the boiler off manually.

That's a new one on me!
 
As I said before

Your benchmark will be filled out (hopefully) and there is a requirement to provide interlock. A room stat is the simplest and most common way of doing this. I would be questioning whether you have chosen the right installer for the job if they do not recognise this requirement regardless of personal opinion. If we could pick and choose what reg's to abide by then it would make the job a lot easier but ..... Unregulated?
 
No, the rads sound like they have got air in them, they are hissing but when i bleed them no air comes out. Its a very annoying noise.
If I was you I would concentrate on getting everything working first. I think you should ask the fitter to come back and look at the noise/air issue.
 
A simple explanation ?
Boiler interlock is not a physical device but an arrangement of the system controls (room thermostats, programmable room thermostats, cylinder thermostats, programmers and time switches) so as to ensure that the boiler does not fire when there is no demand for heat. In a system with a combi boiler it can be achieved by fitting a room thermostat.
In a system with a regular boiler it can be achieved by correct wiring interconnection of the room thermostat, cylinder thermostat, and motorised valve(s). It may also be achieved by more advanced controls, such as a boiler energy manager. TRVs alone are not sufficient for boiler interlock
 
Status
Not open for further replies.

Reply to should i have a room thermostat with my combi boiler. in the Plumbing Jobs | The Job-board area at PlumbersForums.net

Similar plumbing topics

Hi they used to say as a last resort you could discharge the D2 pipework at high level and turn it back to the wall. Similar to a combi boiler. I have just looked back through the regs this seems to have changed and it isn't mentioned now. It now mentions if at high level it should be discharged...
Replies
11
Views
229
Hello, I am seeking some advice, I have a POTTERTON PROMAX 28 COMBI Boiler and I noticed yesterday that the water around the house is no longer warming up. The heat exchanger has been changed 6 months ago, so I do not believe it is that. Does anyone have any ideas on what it could be? Thanks
Replies
4
Views
216
I have an ideal vogue max S18 boiler and I’m considering fitting auto balancing TRVs, my question relates to the boilers pump. I see a boiler pump menu for either 70% or 100%, so, is the pump set at either one of two fixed speed percentages or does the pump actually vary speed, (modulate)...
Replies
1
Views
137
Every two weeks or so I have to go and top up the system because the hot taps are running cold. Boiler display is flashing 0.6 bar and I fill up to 1.3. I've had an engineer look inside the boiler and he can't see anything wrong. I've checked the pipes all over the house and cannot see any...
Replies
1
Views
102
Hello plumbers in my internet. So the Mrs want a spray mixer tap in the kitchen as we had two separate taps. I changed the tap for a temporary two hole mixer but the cold water pressure is high mains fed and the hot is low pressure immersion tank fed. I've been trying to find info on what I...
Replies
2
Views
82
Creating content since 2001. Untold Media.

Newest Plumbing Threads

Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock