Sorry To Bring Up TRV's Again

[Jaymc]

Hello,

Still trawling through the web trying to educate myself!

I'll keep it simple

Q, Do I need TRV's and where?
Q, Whch manufacturer?
Q, Any suggestions for online purchase, or anywhere near Chester?

As with most things these days, I've seen arguments for and against

Cheers

Jay

 

[newcastle phill]

1. Yes and preferably on a radiator
2. How much do you want to pay
3. Yes online purchases can be a good thing

So have i

 

[ShaunCorbs]

every rad but one (heat leak normally bathroom)

danfoss ras-c2

depends which side to chester are you if your wrexham side pts

 

[dancinplumba]

everyone except in the room where room stat is situated

 

[Jaymc]

Thanks Newcastle Phill, very informative, hardly worth the effort of typing was it?

If you don't like the content, don't reply!

 

[SimonG]

Lighten up ffs.

 

[ShaunCorbs]

Thanks Newcastle Phill, very informative, hardly worth the effort of typing was it?

If you don't like the content, don't reply!

now a comment like that is not going to help you out on here so lighten up, or you wont last long!, and tbh i dont think theres anything wrong with his post and the same could be said about your post

dont bit the hand thats giving you information

 

[Ray Stafford]

Its 11:30, nearly time for bed, and I'm trying to decide which poster to assist.

Hmm. Moving on...

 

[Jaymc]

Wasn't typed as maliciously as you appear to be reading it?
I guess if I didn't like his answer, I too could have ignored it, It appeared sarcastic to me, that's why I replied.

 

[ShaunCorbs]

Wasn't typed as maliciously as you appear to be reading it?
I guess if I didn't like his answer, I too could have ignored it, It appeared sarcastic to me, that's why I replied.

you asked a question and got your answer but here you go (translated)

Do I need TRV's and where? : Yes and preferably on a radiator (yes as stated in building regs ,where else you going to put one?????)

Whch manufacturer? : How much do you want to pay ( there are hundreds of types/ manufacturers the top ones are honeywell,danfoss, drayton and ranging from £2 upto £300)

Any suggestions for online purchase, or anywhere near Chester? : Yes online purchases can be a good thing (but they can also be bad eg bits missing best thing to do is find a local plumbing merchants and go down)

hope this help and good night

 

[Dotty]

 

[AWheating]

Any thermostat that reduces the amount of energy used to heat a space is going to save you money, building regs requires that you have them fitted.

Any well known brand will be suitable, after they it's what you like the look of.

Better stick to a local merchant if possible but you may save a pound or two online I guess. Is there a screwfix near by?

 

[Masood]

Still trawling through the web trying to educate myself! ..... As with most things these days, I've seen arguments for and against.

The web can be hugely useful but sadly there are no laws against stupid people posting. There are no valid arguments against fitting TRVs. They save energy, are required by building regs and make for more comfortable living conditions.

 

[doitmyself]

Q, Do I need TRV's and where?
A brand new system should have TRVs on all rads except in the "reference room", i.e where the wall stat is.
If you are replacing a rad then fitting a TRV is "good practice", but not compulsory.

Which manufacturer?
(In alphabetic order)
Danfoss
Drayton
Honeywell

 

[ShaunCorbs]

Q, Do I need TRV's and where?
A brand new system should have TRVs on all rads except in the "reference room", i.e where the wall stat is.
If you are replacing a rad then fitting a TRV is "good practice", but not compulsory.

Which manufacturer?
(In alphabetic order)
Danfoss
Drayton
Honeywell

Wrong if you are change an old valve for a new one you need a trv unless eg stat or heat leak

 

[Sparkgap]

Would also suggest an auto bypass valve across the system as well so you keep the flow up through the boiler.

 

[ShaunCorbs]

Would also suggest an auto bypass valve across the system as well so you keep the flow up through the boiler.

Or use a rad / bathroom with l/s valves as a heat leak don't need a bypass then

 

[Rickster123]

Or use a rad / bathroom with l/s valves as a heat leak don't need a bypass then

What's this thing with the bathroom rad?? An depending on the type of system fitted there well be a need for an auto bypass.

 

[Masood]

Or use a rad / bathroom with l/s valves as a heat leak don't need a bypass then

Depends on manufacturer. Some absolutely require one. Some specify a minimum percentage of system volume to be uncontrolled by TRVs. If we're giving advice let's try and be accurate!

 

[Masood]

Q, Do I need TRV's and where?
A brand new system should have TRVs on all rads except in the "reference room", i.e where the wall stat is.
If you are replacing a rad then fitting a TRV is "good practice", but not compulsory.

Which manufacturer?
(In alphabetic order)
Danfoss
Drayton
Honeywell

Where did you get that? Anyone could have written it!

Building regs have the full force of law behind them, and Part L1B requires thermostatic control on heat emitters except in certain very restricted circumstances.

 

[ShaunCorbs]

Depends on manufacturer. Some absolutely require one. Some specify a minimum percentage of system volume to be uncontrolled by TRVs. If we're giving advice let's try and be accurate!

Yea that's on new boilers I have a feeling this is an old of appliance

And most decent new boilers will have an internal bypass system

 

[ShaunCorbs]

What's this thing with the bathroom rad?? An depending on the type of system fitted there well be a need for an auto bypass.

Normally on old systems the bathroom rad was used as a heat leak (somthing for the pump to circulate) but I have seen them on the kitchen rad before

 

[Masood]

Yea that's on new boilers I have a feeling this is an old of appliance

And most decent new boilers will have an internal bypass system

Makes no odds mate. Part L stipulates that central heating system upgrade require you to bring up to spec.

And even those boilers with an internal bypass require an external auto bypass, as the internal is too small.

Vaillant EcoTEC definitely do.
Ideal Logic and Vogue - as long as the non-TRV-controlled rad (plus associated pipework) is >10% then no need for external bypass. Bigger systems with smallish towel warmers will not comply with this.
Other manufacturers may have similar requirements but these ones I know for a fact.

On the other hand, Intergas only require one if ALL rads are TRV controlled, but they specify that it has to be at least 20' away from the boiler, which to my mind means that a certain system volume must be made available for heat dissipation. If the non-TRV rad is in the next room, and on a metre of 15mm pipework it's unlikely to be sufficient.

So giving out broad-brush assurances that it's never required is not really helpful. This particular OP might be talking about an old appliance but he may want to upgrade, or others might read the thread!

 

[Jaymc]

Just to clarify,

I'm in the process of getting all the parts to upgrade my current system setup to a combi. It's 9 rads and
2 towel rads, in a 4 bed detached
I've I only ever seen TRVs fitted upstairs, hence the question.
Can someone briefly explain the external bypass?

 

[Masood]

Just to clarify,

I'm in the process of getting all the parts to upgrade my current system setup to a combi. It's 9 rads and
2 towel rads, in a 4 bed detached
I've I only ever seen TRVs fitted upstairs, hence the question.
Can someone briefly explain the external bypass?

In all seriousness Jay, why don't you ask a couple of local GSR engineers to come and quote?

I admire you wanting to learn but there's an old saying that you don't know what you don't know. In other words you don't know where the gaps in your knowledge are so you won't be able to research them. If you miss something out, it could be a very expensive mistake.

In any case you absolutely can't hang the boiler or touch the gas or fluing, so why not get an expert in? He or she will be able to assess whether you need a bypass and explain the reasoning.

 

[zzzjim]

Do check it's not gunked up , before start slowing things down !

 

[ShaunCorbs]

Makes no odds mate. Part L stipulates that central heating system upgrade require you to bring up to spec.

And even those boilers with an internal bypass require an external auto bypass, as the internal is too small.

Vaillant EcoTEC definitely do.
Ideal Logic and Vogue - as long as the non-TRV-controlled rad (plus associated pipework) is >10% then no need for external bypass. Bigger systems with smallish towel warmers will not comply with this.
Other manufacturers may have similar requirements but these ones I know for a fact.

On the other hand, Intergas only require one if ALL rads are TRV controlled, but they specify that it has to be at least 20' away from the boiler, which to my mind means that a certain system volume must be made available for heat dissipation. If the non-TRV rad is in the next room, and on a metre of 15mm pipework it's unlikely to be sufficient.

So giving out broad-brush assurances that it's never required is not really helpful. This particular OP might be talking about an old appliance but he may want to upgrade, or others might read the thread!

Last post on the matter

Ok fair enough but the thing is the op hasn't stated what system he has or what boiler he requires and most main manufacturers of boilers don't as I have phoned up today techs ( related to another matter the main 3) ideal , vaillant and worcester and they have sent me these





Which state you only need an external bypass if you have port valve or a full trv system no heat leak

And put it this way I have never fitted one only replaced due to them not lasting/ working well

Finall thought honest opinion not worth the hassle and extra noise that some make esp if they don't want a mag cleaner which is more important

 

[doitmyself]

Building regs have the full force of law behind them, and Part L1B requires thermostatic control on heat emitters except in certain very restricted circumstances.

If you mean Approved Document L1B, it contains no reference to emitters/radiators or TRVs.

The information I gave comes from The domestic building services compliance guide, which does what it says on the tin.

Section 1.4 is about the status of the Guide, in case you think it's not a relevant document.

Table 3 gives the requirements for a new system, whether it is in a new or existing building.

Item 3 says that each circuit should be provided with

i) ...
ii) ... individual radiator controls such as TRVs on all rads outside the reference room

Table 4 give the minimum standards (to comply with Building Regs) and "Good Practice" advice when replacing components in an existing system, i.e. items which exceed the minimum standard.

Item 3 relates to radiators. There are no Minimum Standards though, obviously, you can't make a system worse, e.g by removing a TRV where one is already fitted. (Unless it's in the reference room with the room stat!)

Good Practice is to fit a TRV, unless the room has a room stat.

 

[LPC]

I brought up a TRV once. It was almost as painful as swallowing it in the first place.

 

[Nostrum]

I'm going to open a can of worms here because I'm bored, halfway through a bottle of red and it's Friday.

The approved documents are for guidance and not compulsory unless the contents is highlighted in green.

If we're spouting regulation, ie enforceable in a court, you'll need to ensure you comply with this for existing dwellings:


L1. Reasonable provision shall be made for the conservation of fuel and power in buildings by:
(a) limiting heat gains and losses—
(i) through thermal elements and other parts of the building fabric; and
(ii) from pipes, ducts and vessels used for space heating, space cooling and hot water services;
(b) providing fixed building services which—
(i) are energy efficient;
(ii) have effective controls; and
(iii) are commissioned by testing and adjusting as necessary to ensure they use no more fuel and power than is reasonable in the circumstances; and
Regulation 40 providing to the owner sufficient information about the building, the fixed building services and their maintenance requirements so that the building can be operated in such a manner as to use no more fuel and power than is reasonable in the circumstances.

:wheelchair:

In an ideal world we'd have no TRVs, well sized radiators, weather comp with a heat curve matched to the building and a suitably sized boiler to the buildings heat losses. TRVs reduce water volume volume through boiler which doesn't help with short cycling and minimum run times.

But instead we opt for 40kw combis for "good hot water flow"

Anyway I'm going off topic and no one cares about all that.

Yeepeee

 

[Jaymc]

Hi Masood,

I have had 4 quotes up to this point ranging from £1800 - £3850 all pretty much for the same work, and thus far I'm not getting a good feel for any of them. Which is pretty much what I was expecting. I've got 3 further quotes next week, one being British Gas.
I'm trying to ascertain what I need, and asking relevant questions so I'm armed with the right information so I can weed out the good from the bad.
I'm quite capable of doing most of the work, but wouldn't touch the boiler, I can deal with water leaks, but not Gas!
If anything this post has shown the difficulties I'm encountering as their are differing opinions amongst yourselves.

Tomorrow I'll be going to several local merchants and try and negotiate some prices. I was asking for Internet sites so I can read the details and make an informed decision on the items I want fitted.

All help and information received gratefuly, and it's interesting hearing different ideas.

Jay

 

[Nostrum]

Out of interest Jaymc, what are you looking for from your 7 quotes?

What would it be that swayed you towards one from another and why? Genuinely interested as you seem to be quite particular (no offense) and where are you based?

oh and what work are you having (maybe) done?

 

[Jaymc]

I'm going to open a can of worms here because I'm bored, halfway through a bottle of red and it's Friday.

The approved documents are for guidance and not compulsory unless the contents is highlighted in green.

If we're spouting regulation, ie enforceable in a court, you'll need to ensure you comply with this for existing dwellings:


L1. Reasonable provision shall be made for the conservation of fuel and power in buildings by:
(a) limiting heat gains and losses—
(i) through thermal elements and other parts of the building fabric; and
(ii) from pipes, ducts and vessels used for space heating, space cooling and hot water services;
(b) providing fixed building services which—
(i) are energy efficient;
(ii) have effective controls; and
(iii) are commissioned by testing and adjusting as necessary to ensure they use no more fuel and power than is reasonable in the circumstances; and
Regulation 40 providing to the owner sufficient information about the building, the fixed building services and their maintenance requirements so that the building can be operated in such a manner as to use no more fuel and power than is reasonable in the circumstances.

:wheelchair:

In an ideal world we'd have no TRVs, well sized radiators, weather comp with a heat curve matched to the building and a suitably sized boiler to the buildings heat losses. TRVs reduce water volume volume through boiler which doesn't help with short cycling and minimum run times.

But instead we opt for 40kw combis for "good hot water flow"

Anyway I'm going off topic and no one cares about all that.

Yeepeee

I care LOL. A lad who works for me, has a brother who is a plumber in Poland, and he mentioned pretty much your last paragraph as being the norm over there! We were discussing it, as he was buying a weather compensator for his Vaillant, which I'll be asking about next...........

 

[Nostrum]

We've created a market where cost and speed come before design and basic scientific principles. We will struggle to get out of that mindset now in the common market, so we invent things to combat the problems it causes! Bizarre really. :crazy:

 

[Jaymc]

Out of interest Jaymc, what are you looking for from your 7 quotes?

What would it be that swayed you towards one from another and why? Genuinely interested as you seem to be quite particular (no offense) and where are you based?

oh and what work are you having (maybe) done?

Out of interest Jaymc, what are you looking for from your 7 quotes?


What would it be that swayed you towards one from another and why? Genuinely interested as you seem to be quite particular (no offense) and where are you based?


oh and what work are you having (maybe) done?

Hi Nostrum,


I have a 4 bed detached, 1.5 bathrooms, 9 rads, running on an Ideal Elan 2, and I think? An Albion Mainsflow tank located on my upstairs landing.
I'm asking for old stuff out, a flush, and a WB ? CDI in its place. With the WB filter to get the maximum Warranty. I'm removing all the rads and replacing myself, and have offered to assist if required opening up work to smaller businesses, as they are normally just a one man unit.


I am incredibly picky, and expect a good level of service, knowledge and skill, this is ingrained as part of my previous role as an aircraft engineer.
I may have frightened some off with my expectations, but it shows a lack of professionalism to me.
I run a team of 15 engineers, and expect the same levels from them. I almost want someone to bore me with knowledge, and offer more than one option. The current quotes are pretty much "tear it out and start again" Not one of them has offered anything else other than the combi route, and I've sort of swayed myself in that direction, because some of them weren't able to make sense of the system I have?
I've also been told to fit 3 different sized combis (all WB) and as a note, they're all from the WB accredited installers list.


Well you did ask LOL

 

[Nostrum]

Hi Nostrum,


I have a 4 bed detached, 1.5 bathrooms, 9 rads, running on an Ideal Elan 2, and I think? An Albion Mainsflow tank located on my upstairs landing.
I'm asking for old stuff out, a flush, and a WB ? CDI in its place. With the WB filter to get the maximum Warranty. I'm removing all the rads and replacing myself, and have offered to assist if required opening up work to smaller businesses, as they are normally just a one man unit.


I am incredibly picky, and expect a good level of service, knowledge and skill, this is ingrained as part of my previous role as an aircraft engineer.
I may have frightened some off with my expectations, but it shows a lack of professionalism to me.
I run a team of 15 engineers, and expect the same levels from them. I almost want someone to bore me with knowledge, and offer more than one option. The current quotes are pretty much "tear it out and start again" Not one of them has offered anything else other than the combi route, and I've sort of swayed myself in that direction, because some of them weren't able to make sense of the system I have?
I've also been told to fit 3 different sized combis (all WB) and as a note, they're all from the WB accredited installers list.


Well you did ask LOL

No it's fair enough. Where are you?

Being a WB installer means they can offer you a free WB branded whoopee cushion on request and a mass produced boiler to boot. If you're after a poorly engineered piece of kit with the advantage of feeling secure that they can afford to sponsor the regional weather, then you're in safe hands.

Of course, we all have our own favourites but most of the guys who I'd trust to fit a boiler for me, wouldn't specify a Worcester.

Then there's British Gas, who'll send a shiny suited salesman (unlikely to be gas qualified and sales led) and who require a massive turnover to maintain profit. They'll most likely send a one man band in to actually fit they boiler by the way. Oh and the long warranty you'd normally get is reduced to 1 years homecare, with the option to continue paying a monthly fee for ongoing cover.

Personally if it was me quoting, I'd be asking why you want a combi?

 

[Jaymc]

I'm in Chester.

Interesting observations of WB? What's your weapon of choice?
I was considering a combi as I gain the space from loosing the tank giving me a 6x3 space to utilise better

Regarding the non combi route, I wouldn't know where to start, looks like many options that I don't understand.

 

[ShaunCorbs]

how many are there living in the house?

 

[Jaymc]

2 adults, 2 kids Shaun.

 

[ShaunCorbs]

2 adults, 2 kids Shaun.

i would go with a system boiler/heat only then a 250-300 L unvented cylinder

 

[Masood]

i would go with a system boiler/heat only then a 250-300 L unvented cylinder

Definitely. Not a household suitable for a combi..

 

[Jaymc]

My other problem with the storage tank is that the heat is unbearable in the summer, but welcome in the winter, its very hot in there, tank is old and probably not very thermally efficient compared to the new types?

We're quite efficient in our water use, very few baths and as a shift worker I shower at work, so consumption isn't huge?

 

[ShaunCorbs]

My other problem with the storage tank is that the heat is unbearable in the summer, but welcome in the winter, its very hot in there, tank is old and probably not very thermally efficient compared to the new types?

the new types will be 1000% better at keeping the heat in, does the old one have a jacket on it?

 

[Masood]

I'm going to open a can of worms here because I'm bored, halfway through a bottle of red and it's Friday.

The approved documents are for guidance and not compulsory unless the contents is highlighted in green.

If we're spouting regulation, ie enforceable in a court, you'll need to ensure you comply with this for existing dwellings:


L1. Reasonable provision shall be made for the conservation of fuel and power in buildings by:
(a) limiting heat gains and losses—
(i) through thermal elements and other parts of the building fabric; and
(ii) from pipes, ducts and vessels used for space heating, space cooling and hot water services;
(b) providing fixed building services which—
(i) are energy efficient;
(ii) have effective controls; and
(iii) are commissioned by testing and adjusting as necessary to ensure they use no more fuel and power than is reasonable in the circumstances; and
Regulation 40 providing to the owner sufficient information about the building, the fixed building services and their maintenance requirements so that the building can be operated in such a manner as to use no more fuel and power than is reasonable in the circumstances.

:wheelchair:

In an ideal world we'd have no TRVs, well sized radiators, weather comp with a heat curve matched to the building and a suitably sized boiler to the buildings heat losses. TRVs reduce water volume volume through boiler which doesn't help with short cycling and minimum run times.

But instead we opt for 40kw combis for "good hot water flow"

Anyway I'm going off topic and no one cares about all that.

Yeepeee

If you mean Approved Document L1B, it contains no reference to emitters/radiators or TRVs.

The information I gave comes from The domestic building services compliance guide, which does what it says on the tin.

Section 1.4 is about the status of the Guide, in case you think it's not a relevant document.

Table 3 gives the requirements for a new system, whether it is in a new or existing building.

Item 3 says that each circuit should be provided with

i) ...
ii) ... individual radiator controls such as TRVs on all rads outside the reference room

Table 4 give the minimum standards (to comply with Building Regs) and "Good Practice" advice when replacing components in an existing system, i.e. items which exceed the minimum standard.

Item 3 relates to radiators. There are no Minimum Standards though, obviously, you can't make a system worse, e.g by removing a TRV where one is already fitted. (Unless it's in the reference room with the room stat!)

Good Practice is to fit a TRV, unless the room has a room stat.

Interesting how different people read things differently!

My interpretation of both these documents is that you take all measures to reduce energy consumption. Which, in the absence of a truly cohesive whole-house, weather compensated, fully insulated design, means TRVs, zoning and time/temp controls!

 

[Nostrum]

I'd be recommending a decent heat only boiler around 12-15kw (guessing it a relatively modern home but needs calculating) on a clean sealed system and replacing the cylinder if required. Weather compensation if the current system is up to it and rads are well sized.

A 12kw boiler will modulate down to about 4kw (maybe less) so will be able to tick over matching the heat loss of the building.

A 30kw + combi would modulate down to about 8kw which is probably about your buildings heat loss at -1 outside. Therefore for a large percentage of the year, the boiler is outputting more than the house is losing, return temperature goes up and boiler turns off frequently.

You'll also get a better hot water flow rate from the cylinder, so basically when you think about it, a combi does both jobs, worse.

 

[Jaymc]

No jacket, just externally insulated with expanding foam type material.

Could you suggest a boiler and a tank? I can run off and educate myself further? :bigcry:
I can see some specs, and look at some alternatives.

 

[Nostrum]

Interesting how different people read things differently!

My interpretation of both these documents is that you take all measures to reduce energy consumption. Which, in the absence of a truly cohesive whole-house, weather compensated, fully insulated design, means TRVs, zoning and time/temp controls!

Hi Masood,

The clue is in the bit no one can ever be bothered to read (including me until it was pointed out by somebody else!)

It reads:

"Approved documents set out what, in ordinary circumstances, may be accepted as reasonable provision for compliance with the relevant requirements of the Building Regulations to which they refer. If you follow the guidance in an approved document, there will be a presumption of compliance with the requirements covered by the guidance. However, compliance is not guaranteed; for example, ‘normal’ guidance may not apply if the particular case is unusual in some way."


Then:

"Note that there may be other ways to comply with the requirements – there is no obligation to adopt any particular solution contained in an approved document. If you prefer to meet a relevant requirement in some other way than described in an approved document, you should discuss this with the relevant building control body."

 

[Jaymc]

Now this is why I used the forum!

I hadn't ruled out replacing like for like, but the choice is bewildering, but I realise the benefits of what you're suggesting. And the specs of the boilers for heat and water are clearly less.
Are install costs similar? I'm thinking it would be easier as it's a straight swap?

 

[ShaunCorbs]

worcester r18/24 depending on size (worked out room sizes and cylinder need)

if you want

worcester cylinder 250-300 depending on need

rm Stelflow """ """ """ """ """ """ """

the cost is hard to say without seeing it but i think it wouldn't be too far off depends on spec tbh

 

[Nostrum]

No jacket, just externally insulated with expanding foam type material.

Could you suggest a boiler and a tank? I can run off and educate myself further? :bigcry:
I can see some specs, and look at some alternatives.

Personally, for various reasons

Ideal Vogue is a good value, respectable quality and low modulating boiler (good for combi and system because of said modulation)

We've now taken on the ATAG compact range. Very good quality with good controls (one controller) although admittedly a new product, the previous ATAG ranges have been first class.

Also, Intergas for another good quality product. Really only benefit in combi form due to the heat exchanger design.

Viessmann also get a lot of praise although I've not had much dealing with them.

For cylinders, much of a much in my opinion although we use Joule as they offer the best range for just about any situation.