How to change leaking valve when other radiator valve stuck open

[OliSmi]

I have a towel rail style radiator in the bathroom with straight through taps.

I have noticed tonight one of the valves has started dripping. I can sort some new valves but the other valve that isn't leaking appears to be stuck open.

How do I best drain the radiator to change the valves given I cant actually turn one of them off.

Left valve leaking. Right valve stuck open.

 

[Timmy D]

Even if both valves worked. You then need to disconnect/drain/potentially remove rail.

Now you are left with a dripping valve which is still holding back the heating system pressure.

You can’t just take it off. You would either need to drain the system or dump the pressure and quickly pull off the old and slam on the new. If you’re not experienced, this option could result in a lot of water.

Because you have a stuck valve, you can’t isolate the rail to dump the water.

So either drain down and change both.

Or dump the pressure and air lock it. Or undo rail on one side and if there’s a bit of play in the pipe, pull the valve out of the way and get someone else to stop the rail dumping it’s water with the palm of their hand.

All this also depends on if the system is pressurised or open vent. If open vent you also need to isolate the feed and expansion.

From the information you’ve provided, it’s safer to drain down.

Out of interest, where is the valve leaking? Handle stem? Could just replace packing.

 

[OliSmi]

Even if both valves worked. You then need to disconnect/drain/potentially remove rail.

Now you are left with a dripping valve which is still holding back the heating system pressure.

You can’t just take it off. You would either need to drain the system or dump the pressure and quickly pull off the old and slam on the new. If you’re not experienced, this option could result in a lot of water.

Because you have a stuck valve, you can’t isolate the rail to dump the water.

So either drain down and change both.

Or dump the pressure and air lock it. Or undo rail on one side and if there’s a bit of play in the pipe, pull the valve out of the way and get someone else to stop the rail dumping it’s water with the palm of their hand.

All this also depends on if the system is pressurised or open vent. If open vent you also need to isolate the feed and expansion.

From the information you’ve provided, it’s safer to drain down.

Out of interest, where is the valve leaking? Handle stem? Could just replace packing.

It's actually leaking from the centre tap, I imagine through the worm screw. Its not the threads that are leaking. Based on your feedback I think asking a pro to sort may be the option. I change radiators for fun normally but this seems to be an accident waiting to happen. Don't want to make a bigger mess

 

[Gasmk1]

is it stuck open or are you turning it the right way if leak is from the middle then the gland just needs packing with ptfe and tightening up. these type of valves don't like to be opened and closed all the time best to leave alone.

 

[OliSmi]

is it stuck open or are you turning it the right way if leak is from the middle then the gland just needs packing with ptfe and tightening up. these type of valves don't like to be opened and closed all the time best to leave alone.

It's been left well alone by me. It appears to have attracted the attention of my 3yr old.
Drips far far slower when uts open, so I'm currently living with it like that.

The other is 100% stuck open. I'm nervous of encouraging it too much and making the situation worse