Radiator valves suitable?

[Jack07]

Hi,

I've purchased some anthracite radiator valves (ebay) to hang a new tower radiator and wanted to double check as they are not what I expected when they arrived.

I've attached an image to help. Firstly, the brass/chrome threads shown aren't like the picture as they've also been coated in the paint. I was wondering if this could cause a potential issue when creating a seal?

Secondly, the thread that screws into the rad has a 15mm tail (again, painted) which the valve then has a compression fitting to secure. Is this a normal way of fixing a valve as I was expecting the larger BSP thread. So if I ever wanted to remove the radiator I would need to loosen a compression fitting rather than just unscrewing?? I can send photos of my valves of easier.


Thanks

 

[Madrab]

Yes, they're absolutely fine with 15mm compression.

Run the tails in and out of the rad a few times to clean the threads of the paint before doing the final fit with PTFE Tape or cord or whatever your pleasure is.

the only concern I may have is where they came from, EBAY aren't known for their quality fittings/suppliers unless, you're buying known manufacturers and they aren't copies

 

[ChrisJP]

These valves follow the newer trend to attach the valves via a 1/2"BSP stub that screws into the radiator and then connects to the valve via a compression fitting. These are fine but they do have the disadvantage over the older type "cone" fitting of making it more difficult to remove the radiator in the future without disturbing the valves, which can, with the older fitting, be shut and just the radiator itself drained.
With the older type fitting, there was nearly always enough play in the pipes to ease the cone and socket apart and remove the radiator and, with the valves closed, just the radiator can be drained.
With the newer fitting, you need enough play in the pipes to withdraw the length of pipe inserted into the compression fitting, and often this amount of play is just not there. So removing a radiator then entails draining the whole central heating system so the valves can be removed

 

[Madrab]

So removing a radiator then entails draining the whole central heating system so the valves can be removed

Cant agree there - if the system is sealed then it's just a case of shutting down all the other rads and then all that's needed is the system de-pressurised and the rad itself drained, there should be no need for a system drain down.

Even if the system is open vent then the F&E can bunged and a partial vacuum created that minimises water loss, especially if you have a few extra bungs to hand.

@Jack07 , can I presume that the feeds for the rad aren't up through the floor as they're angled valves that wouldn't be suitable, you would need straight valves in that scenario. Even if the feeds are out from the wall those wouldn't be ideal unless you don't mind the head of the valve sticking straight out or straight down, corner valves may be more suitable.

 

[Jack07]

Yes, the feeds do come out from the floor and the valves are angled correctly. I've fitted all the valves ready but when screwing the thread into the radiator with PTFE, it doesn't have a stop on it, so I'm not sure how far the thread screws in to the rad itself?

 

[ChrisJP]

You need to put enough PTFE tape on the threads so the tail screws into the radiator and tightens with just the start of the threads showing. In my experience this always takes more PTFE tape than you expect.

 

[Madrab]

If you use gas PTFE tape then 7 wraps will do it. I don't use water PTFE as I always have gas tape to hand, so couldn't suggest how many is needed if using that.