1 inch rad valve?

[bpowell555]

One of my cast iron bathroom rad's valves is knackered. While I may be able to fix it if I took it off this is a drain the system job so I want to have a good replacement if necessary. BUT, measuring similar valves since taking those rads off to be sandblasted it looks like the rad-side fitting is 1 inch and I can't find anything with a 1 inch fitting.

Have I measured it wrong? Will 22mm or 3/4 inch work? The pipework is 15mm. I may just drain the system to take it off and have a service valve handy... Even so, anyone heard of a 1 inch valve? The only company I can find on google is radiator plus in Ireland

Cheers!

 

[TicklyT]

If the thread on the fitting is about 1" diameter, it will probably be 3/4" BSP.
A 1" BSP thread is about 1 1/4" diameter.

Imperial pipes and fittings are sized according to the bore of the pipe, rather than the outside diameter.

Metric copper pipe is sized by the outside diameter. That's why 15mm copper pipe is almost indistinguishable from imperial 1/2" copper pipe, and why 15mm pipe fittings can have a nominal 1/2" thread (which is actually about 3/4" dameter).

You could consider using a 1" Male X 3/4" Female iron reducer (or whatever is appropriate for the radiator tapping and valve sizes you have) between the radiator and valve.

 

[bpowell555]

Hi Tickly, thats reassuring/makes sense/interesting bit of knowledge! Sounds like it could be 3/4 then.. but why would I need a reducer if that's the case? Don't understand ... The radiator end is the male connection and I measured the inside of the nut on the valve as 1 inch, which would make the thread an inch, which you're saying is 3/4. That's all good - there's loads of 3/4s out there!

Cheers!



May just keep a service valve handy just in case !!!

 

[Agile]

All rads I have ever seen have female connections.

You are confused by the pipe sizes! Screwed iron sizes are based on the internal bore of the pipe so a 1/2" pipe will have a thread which is 3/4 o.d.

Its much easier to use a reducing bush and standard 1/2" rad valves.

Tony

 

[ChrisR]

You can get chrome bushes if you googl;e.

 

[bpowell555]

All rads I have ever seen have female connections.

You are confused by the pipe sizes! Screwed iron sizes are based on the internal bore of the pipe so a 1/2" pipe will have a thread which is 3/4 o.d.

Its much easier to use a reducing bush and standard 1/2" rad valves.

Tony

ahh sorry that was me at 1am this morning!!! Of course yeah the rad is the female end

Reducing bush - that's a good idea, then I can maybe just get everything from screwfix

Cheers!

 

[bpowell555]

Hi, is Plumb Centre a good place to get a reducing bush? There's one fairly close by I should be able to get to on saturday...

Cheers!

 

[doitall]

Are you measuring the tail that screws into the rad or the nut on the valve

 

[bpowell555]

Measured the nut on the rad...

 

[ChrisR]

What nut on the rad? They usually just have holes.
Measure the hole!
Not a double entry one is it, ie 2 pipes same hole?

 

[chrishutt]

I think the radiator tails are still attached to the rad and the OP thinks they are part of the rad. The so-called 1" thread is the ¾" thread of the union nut.

Bpowell, the chrome piece sticking out of the bottom of the rad is part of the rad valve. You have to unscrew it. If it doesn't have external flats for a spanner then it will have an internal hexagon (Allen key) shape. You may need a special radiator tool to remove it.

 

[bpowell555]

I think the radiator tails are still attached to the rad and the OP thinks they are part of the rad. The so-called 1" thread is the ¾" thread of the union nut.

Bpowell, the chrome piece sticking out of the bottom of the rad is part of the rad valve. You have to unscrew it. If it doesn't have external flats for a spanner then it will have an internal hexagon (Allen key) shape. You may need a special radiator tool to remove it.

??! What's OP? "¾" thread of the union nut" - that makes sense, but am I looking to replace the radiator tails as well then? What am I going to do if I measure the hole, aren't I going to attach the valve to the tail anyway?

Cheers chaps!

 

[bpowell555]

This is another one of the taps that isn't leaking! The one inch measurement is the inside of the gold nut in between the rad and the valve, which is the radiator tail? Why would I want to take that off?



Cheers!

 

[Timmyturtle]

Looks like a standard (older)style rad valve thats just goldie
Just a case of whether the pipe going into the bottom of the valve is 15mm/22mm or something else

 

[Timmyturtle]

What size is the pipe that comes out of the floor?