Thermostatic valves for imperial radiators ?

[webless]

Hi,

I have a new boiler but a house full of imperial radiators, some of which are curved (due to window bay) and likely to be expensive to replace the whole set.

I need to fit thermostatic valves but everything on the market seems to be metric.

Is there a imperial to metirc convertor or imperial thermostatic valve option so i can avoid replacing radiators?

Regards

W.

 

[tonybhoy]

Metric smetric Same size mate they're all 1/2" X 15MM, well they're not all the same size but in the main domestic stuff is. So the rad will be either 1/2" or 3/4" with a 1/2" bush (or you may have to fit a bush if it's 3/4") and the pipe size will 1/2" or 3/4" in which case your in trouble.

 

[webless]

Thanks for the quick reply,

thats interesting as the plumber said cant fit valve to those radiators because they are imperial - seems he's not right then...

Regards

W

 

[tonybhoy]

Thanks for the quick reply,

thats interesting as the plumber said cant fit valve to those radiators because they are imperial - seems he's not right then...

Regards

W

Hard to say from here mate, sitting in front of a PC, but I've never heard of imperial radiators causing problems fitting a TRV.

Imperial rads usually refer to the size of the rad (LXH) in inches and metric rads the size of the rad in cms.

Rad tails are almost always 1/2" female threads but on very old rads they are usually 3/4" bushed down to 1/2" on some occasions the rad valve tail on these older rads are 3/4" mail threads.

You'd be bettter off taking a few pics and sticking them on here so we can have a look to be honest

 

[webless]

thanks very much, ok I'll challenge the message from plumber and get some more detail, then if no joy post up some images.

many thanks !!

 

[cmother1]

Sounds like he wants to flog you some new rads (+ fitting). If he's BSing about imperial pipe sizes there's no problem joining 15mm to 1/2", and you can get convertors for 22mm to 3/4".

 

[doitall]

Thanks for the quick reply,

thats interesting as the plumber said cant fit valve to those radiators because they are imperial - seems he's not right then...

Regards

W

Work for BG does he.

Well it's either that or a 10 week CC.

 

[JohnD]

it is possible that your old rad valves have a 3/4" union fitting. These are rarely seen now, and tend to be expensive. However, they are (almost certainly) fixed to a tail which is screwed into the radiator (the radiator has a standard thread) so the thing to do is to unscrew the old tail (this can be quite hard work) and fit the new tail that is supplied with the new valve. The new tails and radiator threads are still the old imperial size as standard.

All this is much easier if the pipes come up through a wooden floor and have a bit of play in them as the new valves may be a different size. If the pipes are set into a concrete floor and are immovable it is a real drag.

I recently was doing this and had some tails that wouldn't come out (they were too tight, and a poor fit to the more common radiator spanner), after advice on here I bought this thing which fits a 1/2" socket set ratchet handle, and should do the trick

PWM0246 Radiator Step Wrench
(Monument brand)
If you can post some pics of your old valves someone will recognise them //www.diynot.com/forums/viewtopic.php?t=129539


I am not a pro.

 

[roberta1000]

thats interesting as the plumber said cant fit valve to those radiators because they are imperial - seems he's not right then...

No, he's right enough, mine were the same and today's valves don't fit, quite a different thread.

As suggested above the inserts in the radiator itself can likely be replaced with modern equivalents which will then fit the new valves. However as your radiators must be fairly old there are some risks with removing them, as it can take quite a bit of force depending on the degree of corrosion around them.

You'll probably find that the valves _don't_ come with a new insert (mine didn't) as these normally come with the radiator but they're easy to get hold of and cost little. You only need to replace 1 side for the new valve of course - just leave the other as is.

 

[Rico99]

robert,

Every rad valve I've ever bought has come with the rad tails in the pack.

Rico

 

[doitall]

robert,

Every rad valve I've ever bought has come with the rad tails in the pack.

Rico

I think Roberts having a funny moment

 

[skipdy]

15mm TRV's come with a 1/2BSP tail and 15mm fittings.

1/2BSP valves(imperial) come with a 1/2"BSP tail and 1/2" BSP fittings

1/2" British Standard Pipe threads will not fit onto a METRIC 15mm threads, they are physically different

Drayton supply both imperial and metric valves. If in doubt speak to there tech cell on 0845 130 7722

Hi,

I have a new boiler but a house full of imperial radiators, some of which are curved (due to window bay) and likely to be expensive to replace the whole set.

I need to fit thermostatic valves but everything on the market seems to be metric.

Is there a imperial to metirc convertor or imperial thermostatic valve option so i can avoid replacing radiators?

Regards

W.[/quote]

 

[doitall]

15mm TRV's come with a 1/2BSP tail and 15mm fittings.

1/2BSP valves(imperial) come with a 1/2"BSP tail and 1/2" BSP fittings

1/2" British Standard Pipe threads will not fit onto a METRIC 15mm threads, they are physically different

Drayton supply both imperial and metric valves. If in doubt speak to there tech cell on 0845 130 7722

Hi,

I have a new boiler but a house full of imperial radiators, some of which are curved (due to window bay) and likely to be expensive to replace the whole set.

I need to fit thermostatic valves but everything on the market seems to be metric.

Is there a imperial to metirc convertor or imperial thermostatic valve option so i can avoid replacing radiators?

Regards

W.

[/quote]

So you are saying I can't strip an old radiator and fit a new valve

Absolute rubbish. I have fitted thousands of radiator valves, old and new in the last 50 years, and not had a problem yet.

 

[kevindgas]

been doing boilers & rads for over 35 years yet to find a single rad that isn't 1/2" female BSP thread.
the only bit that differs is the central connection between tail and valve these i have only ever seen in 1/2" and 3/4" BSP !

 

[Nige F]

Webless ,You aint got a plumber."advising" you..you got a gas fitter with a degree