Lock Shield Radiator Valve Question

bloke91

Hi all,

Looking for a bit of advice.

The top of the lock shield radiator valve has snapped off as circled in the attached picture.

In terms of replacing the snapped off part.  I presume would have to drain the radiator, turn off the water and then swop the entire lock shield radiator valve?

Just weighing up if it's something easy and I could attempt to swop it myself vs getting a trades person in.

Thanks in advance for your input.

Ectophile

I guess if you can find a new valve of the same make and model, you could unscrew the inner brass insert and swap only that.

But you'd still have to drain the whole system down first.

Grenage

Or freeze the pipe, if needs be.

ThisIsWeird

This is a lockshield, Bloke? Why were you adjusting it? Was it fully open or fully shut? Why did it snap? Do you think the spindle will actually move? What sort of cap did it have on it? Do you know the make - what's on the other end? Is your system pressurised?

FreeBear

Ectophile said:

I guess if you can find a new valve of the same make and model, you could unscrew the inner brass insert and swap only that.

But you'd still have to drain the whole system down first.

Lockshields are cheap enough. Not much point in trying to salvage parts to make a repair.

After draining the system down, a good opportunity to give it a flush, fit a magnetic filter if there isn't one already, and add some fresh corrosion inhibitor.

MikeJXE

Fit a new valve £6.30 from Wicks, tape about 25p

Switch off at the mains, close all other rads, Drain the system,

Easy enough job, just bind the threads with a few layers PTFE tape before tightening up 

I swapped a radiator last week and I’m 83

Look on YouTube for demo 

ThisIsWeird

Ectophile said:

I guess if you can find a new valve of the same make and model, you could unscrew the inner brass insert and swap only that.

But you'd still have to drain the whole system down first.

Ecto's idea is a cracker, would be a full cure, and carryoutable in 5 seconds if it's a pressurised system.
If you fully depressurise a sealed system by, say, bleeding from a radiator, then you will almost certainly find that you can swap such a part with barely a thimbleful of water loss. This is because air needs to get in to replace any water coming out - at most, you'll get slow glugs, and this would be a sub-one-glug task.
I replaced two 2-port motorised valves without draining or isolating my system. Yes, they were on the side of an upwards pipe loop, but the point is that I was able to fully remove them (one at a time...) clean up and compound the olives, and fit the new ones with hardly any water coming out - and that dribble was easily caught on a towel.
With the body of this valve facing upwards, I am as certain as a certain thing that the broken insert can be removed and the replacement inserted with only a thimbleful of loss - easily caught by a towel. The actual swap will take 2 seconds.
Close off the control valves of all rads (don't touch their lockshield or you'll introduce another element into the whole process), depressurise the rad this valve is on until not a drop comes out the bleed screw, and then retighten it. Undo the valve insert until it can be completed by hand, and 'test' that water ain't spurting out, then swap - it'll take a second.
If...they are the same :-)
Possibly even do the depressurising in the evening, and the valve swap in the morn - you'll almost certainly find the system is partly vacuous in the cool morn, unlike Ecto's idea ddddrrrr-cheesh.

FreeBear

MikeJXE said: Easy enough job, just bind the threads with a few layers PTFE tape before tightening up

PTFE tape should only be used on taper thread joints (e.g. the tails that screw in to the radiator). For compression joints, a thin smear of jointing compound can be used.