The law and TRVs

[AJames]

Hello,

This isn't strictly a DIY question, but you guys seem very knowledgeable, so I hope you don't mind?!?

I'm looking to get our central heating system modernised by installing a combi boiler and getting rid of the water tanks etc. Several plumbers have come round to give us quotes, and all but one have insisted that TRVs must be installed by law. The other plumber was the most professional of the lot, so I would find it surprising if he's wrong (especially as he would be losing out by not installing them).

If anyone knows the answer could you let me know, and if there's any web link which provide evidence either way, that would be great.

Thanks in advance

 

[stem]

You should find this useful

http://www.idhee.org.uk/TACMAGuide.pdf

http://www.gasman.fsbusiness.co.uk/images/part_l_guidelines.pdf (added as edit 1)

Fit them anyway, you'll be more comfortable, reduce your bills and do your bit for the planet.

 

[baxpoti]

''Boiler interlock is achieved by the correct use of the room thermostat(s) or programmable room thermostat(s), the
cylinder thermostat and zone valve(s) in conjunction with the timing device(s). These should be wired such that when there
is no demand from the heating or hot water both the pump and boiler are switched off.

The use of TRV’s alone does not
provide interlock.''



..............Unless the boiler is fitted with a flow switch!

 

[AJames]

Thanks for the help guys.

So am I right in thinking that we would only need TRVs if all the pipework and radiators were being replaced as well (which the aren't)?

The plumber also said that TRVs are useless after about 18 months because they get clogged up with limescale (we live in a hard water area). Any thoughts on that?

Thanks

 

[Rotunda82]

I was under the impression that TRV's must be fitted when upgrading the system/ replacing the boiler/ converting to a combi etc..

 

[gas4you]

When ever a new boiler is fitted to an existing system the whole heating system has to be brought up to current energy efficiency standards.

As baxpoti states this must include a 'boiler interlock' and trv's on EVERY radiator except the one in the room where the room stat is situated,
unless your'e fitting a Vaillant with the weather compensator/programmer/room stat plugged into the boiler front, then trv's will go on all rads

 

[namsag]

So how is he losing out by not fitting them .. how much cheaper was he.

 

[corgiman]

My tuppence worth

Basic practice of CheSS = Boiler interlock (room stat) job done
best " " " = " " and TRV's on all ut interlock served rad

Client gets to choose whether to have them or not unlike steamers and cylinders

 

[Agile]

The plumber also said that TRVs are useless after about 18 months because they get clogged up with limescale (we live in a hard water area). Any thoughts on that?

Thanks

Well thats obviously nonsence!

Limescale is only present once in the initial fill and if a reputable inhibitor is added and the boiler set up correctly at the initial stage then lime scale is not relevant!

Have you checked his CORGI card shows "Energy Conservation" ???

Tony

 

[sambotc]

I thought TRV's now had to be fitted on at least all bedrooms to comply with the new energy efficency rules and reg's?

Sam

 

[gas4you]

I thought TRV's now had to be fitted on at least all bedrooms to comply with the new energy efficency rules and reg's?

Sam

That was the previous regs. Now all rads have to have them as explained above earlier

 

[corgiman]

I thought TRV's now had to be fitted on at least all bedrooms to comply with the new energy efficency rules and reg's?

Sam

when I did my Part l wotsit no that wasnt the case

but as we all know they change stuff hourly so it may well be the case now

 

[sambotc]

If that's the case then barret home's are breaking the rule's day in day out, all new houses in my area only have them in bedroom's! (and roomstat in hall) My girlfriend live's in one which was built 8 month's ago..

When did that come into place~?

Cheers, Sam

 

[corgiman]

If that's the case then barret home's are breaking the rule's day in day out, all new houses in my area only have them in bedroom's! (and roomstat in hall) My girlfriend live's in one which was built 8 month's ago..

When did that come into place~?

Cheers, Sam

see my last

You have Basic and Best practice

they are coming somewhere inbetween

 

[gas4you]

Approx 18/24 months ago. They may have got round by when the building regs plans were passed before this date

Even basic CHeSS now says trv's every rad. Best practice is an optimising programmable room stat, fast recovery cylinder fitted to installation