Roger Mills wrote:
In an earlier contribution to this discussion,
anon wrote:

From earlier posts on this topic it appears that a 'LockShield Valve'
or a 'Radiator Valve' can be used to balance DCH flow.



I think you're getting a bit confused with terminology!

Yes, I'd go along with that Roger! A closer look at my new TRV's (same
'tail' as the LSV's at Screwfix) have olive compression joints - not a
flat washer as I first thought.

or using conical mating surfaces and a back-nut.
I was refering to the tail which has a spherical / radius / torus
seating (to fit the valve cone)

It's worth pointing out LSV's extend a further 10mm so anyone replacing
a RV for a LSV needs to be able to move the pipe or elongate the hole
in the floorboard.

I'm converting a single pipe system to twin pipe and replacing the
radiators for convector type. The old RV's were perfectly servicable so
I've used the best one for upstairs and will probably go for LSV's for
downstairs as they look neat and may have the edge on RV's for
tightening and watertightness.

Many thanks for your comments Roger