Replacing radiator Valves

[psmuk]

In the house i recently moved into, there are old painted up leaking valves on the radiators. I repaired the leaking valve with help from a user on this forum. However they have no control 'knob' on any of the radiators which make altering individual room temperatures hard.

I have watched a video on how to replace valves and looks simple enough, however with the radiators being old 'back then were the sizings different' ?

I dont want to go out buy 5 radiator valves which dont fit, this I would discover when I have empty the water system and taken one off.

I was also thinking of replacing the bleed valves while the water was all drained this looks easy enough.

And one more thing, While I am refilling the system even though the radiators are old would you recommend me to put any additives in the radiators?

Thanks

Gary

 

[Charnwood]

When is 'back then'?
Radiators have been BSP threads since way, way, way back then.

It is the pipe size - if it's copper pipe - you need to worry about.
Imperial up to 1972, then we went metric.

 

[psmuk]

HI there

I believe there copper pipes, but years worth of paint on them. Measuring the pipe going into the valve from the floor looks like 15 mm however the fitting into the radiator there the old type the councils used to fit as this is ex council hose.

 

[psmuk]

whats confusing me a little is the sizes i see online

15mm x 1/2 "

I assume that means 15mm inlet (the bottom) and 1/2" outlet, if so my outlet looks more like just under an inch, but i assume i need to take into account the years of paint on it so maybe 3/4" ? New valves if they didnt fit I can purchase a adapter (i forgot the name of it something tail) however would that not make my pipe out of place to fit the new valve?

Gary

 

[Phill Peck]

If you want to replace your valves you will need to replace the tails that go into the rad. These will come with the new valve but the hard bit is getting the old ones out and removing the nut and olive from the pipe. All of which can be done just be prepared

 

[psmuk]

So all the fittings into the Radiators are standard size and these tails fit into the rad to allow these to be fitted? So current piping will be in place to do this dont need to worry about once tail fitted the valve wont meet the pipe coming from the floor?

 

[Charnwood]

If you want to replace your valves you will need to replace the tails that go into the rad.

Not necessarily.
Leave the tails in the rads, get valves that fit the nut on the tail.

Pictures of the valves would be helpful.

Re size confusion, 1/2" BSP is roughly 3/4" outside diameter.
1/2" refers to the nominal bore (NB) of the pipe that is threaded.

 

[psmuk]

I will get some pic up in a few hours for you

Thanks alot

 

[Phill Peck]

If you want to replace your valves you will need to replace the tails that go into the rad.

Not necessarily.
Leave the tails in the rads, get valves that fit the nut on the tail.

Pictures of the valves would be helpful.

Re size confusion, 1/2" BSP is roughly 3/4" outside diameter.
1/2" refers to the nominal bore (NB) of the pipe that is threaded.

I was trying to be realistic matching the nut/union to these valves is very unlikely
There is a picture on his previous post "leaking gland nut" or something like that. Although you can't see the union in the picture the valve itself gives you an idea.
Removing the tails from the rads I picture these valves connected to would not be easy. I have had to remove the radiators and heat with s blowtorch on many occasions. To change both valves on 6 or so rads I would allow all day.
Not the easiest job for a diyer

 

[psmuk]

Hi there

Here is a pic of the valves if this may assist someone in recommending a replacement valve they are the same on all the radiators in the house.

Thanks

here is the pic

Untitled

• psmuk
• 28 Feb 2012
• 1

 

[Charnwood]

Going back to your original post. You say you want to control individual room temperatures. You would need Thermostatic Radiator Valves (TRVs) to do that, not manual valves. All they do is control flow.
Unless you are going to turn off the valve when the room reaches temperature then back on again when it cools.