Old radiator fittings.

[MickBrown]

Somebody wants me to change some thermostatic valves on old radiators. They have old thermostatic valves already but the fittings are not standard. The pipes are 15mm but the valves are much bigger, the tail in to the radiator is a few mill bigger with a bigger nut to the valve, the valve is much bigger and then there is a reducing fitting to fit the 15mm pipe. Anybody know what size this is and if you can get replacement fittings?

Thanks Mick

 

[gasmarc]

yes they are standard fittings 2 types and usually come with the tails that go into the rad take a pic on your phone and go to a local merchant not plumbase or plumbcentre , If you take one of the valves off you maybe able to replace just the valve with out touching anything else depending on the make good luck

 

[ecowarm]

remove the old tail with something like this Radiator Step Wrench - Monument available at Plumbworld

and fit the new one

 

[MickBrown]

The problem is that the old tail is bigger than the new tail, the nut that normally screws on to the valve is also bigger than the standard 15mm nut.

 

[ecowarm]

http://www.plumbworld.co.uk/radiator-step-wrench-241-38

Remove the old tail from the radiator using a tool like the one above, and then fit the new tail to the radiator and then the new valve will fit

 

[gasmarc]

as i said before you may get a straight replacement valve depending on make which will be a straight swap over just unscrewing old valve and putting new one on

 

[MickBrown]

The problem is not getting the old ones out, but that they are bigger than standard fittings. I cannot take one out and take it to the plumbers merchant as the customer wants to know how much it would cost first. I know I can ask at the plumbers merchant do they have any bigger radiator tails for valves but was just interested if anybody knew of bigger types and their measurements.

 

[turnpin]

any chance of a photo? regards turnpin

 

[MickBrown]

I will ask the customer if he can send me one. It is not that close and not a big money spinner so not worth me going over to take a photo. Will post a photo if he sends one.

 

[PuraTherm]

Sounds like you have the old 1/2 inch threaded type. Check out Danfoss or Honeywell commercial TRV's. These are sometimes twice the cost but if you want a straight swap then this is the only way.

 

[gasmarc]

logic prevails lol

 

[tamz]

They may be 3/4 valves. Depends on how old or what type rad. Take some bushes with you.

 

[ecowarm]

they would have 3/4 or 22mm pipe going to them

 

[tamz]

the valve is much bigger and then there is a reducing fitting to fit the 15mm pipe.

This is what made me think 3/4"

 

[MickBrown]

From what everybody says they I think they must be 3/4" valves, is there any way to reduce the fitting into the rad down to a 1/2" for a standard radiator tail or is it best to find some 3/4 valves?

 

[tamz]

3/4" x 1/2" bushes. Available in brass or iron.

 

[dontknowitall]

Empty the radiator, remove the 3/4" fitting and fit a 1/2" one. The part of the valve that goes into the radiator is always the same size, the outer part is either 3/4" or 1/2".

 

[MickBrown]

Do you know who sells these.

 

[neiln]

Try These: B.E.S Ltd, Plumbing and Gas supplies

you might struggle to get the 3/4 tails out though

and check the 3/4 valves aren't fitted for a reason ie one pipe system / gravity heating system