Old rads with lock shields both ends

[TBN]

Just moved into a 1980‘s built house with oil heating. I’m planning on fitting programmable TRV’s but just realised the rads have old 3/4 connections (with a captive nut at the rad end) so no go with the TRV bodies I’ve got. Clearly old rads, so looks like replacement is the best bet and given they are old imperial sizes I can pick a smaller width metric size and use extended tails to connect which should make it easier to connect and help not put undue stress on the existing pipe work (much of which is buried in the screed). The other odd thing is that all the radiators have lockshields at both ends. Was this normal back then. I’ve never seen it before.
Given that I will have a couple of rooms that will be empty most of the time this winter. I wanted programmable valves to easily shut down heating in those rooms. Presumably, in the meantime I can shut down those rooms by closing one of the lockshields to do the same thing. A bit of a pain but ok until I change the Rads. I’d appreciate any thoughts.

 

[Exedon]

Take out existing rad tail with 3/4 nut and replace with tails that come with trv simple as.

 

[TBN]

Thanks for the reply. I’ve attaced a pic. I assumed there would be insufficient room to replace the tail and fit the TRV body (drayton). It looks very tight or am I wrong. Any idea why all the rads have lockshields both ends?

 

[Madrab]

Nope, looks like the usual amount of space, you will need a radiator tail key to remove the 3/4" union tails though.

 

[TBN]

Thanks Rob (and Exedon) - looks like I found a problem when there wasn’t one. I think what confused me was the valve bodies coming with 15 mm olives. Anyway sorry for wasting your time
.

 

[TBN]

Sorry guys a final question. I’m struggling at the moment to find a like for like tail with a 1/2 BSP captive nut. At the moment all I’m finding are the ones for use with an olive or ones that use a spanner to tighten which will likely be too long. I need a like for like fitting that tightens by way of the Allen key. I’m not seeing the rights ones on the main diy sites.

 

[Exedon]

Nut and olive is how they are
They will go on!
If there really is zero movement on pipework you may have to put trv onto new tail lift rad and drop valve onto copper pipe .
Everyday stuff welcome to our world.

 

[Mottie]

The other odd thing is that all the radiators have lockshields at both ends. Was this normal back then. I’ve never seen it before.

Completely normal in the days before TRV's. One will be a lockshield and one will be for the flow. When you buy a new lockshield valve, it comes with two plastic heads - one that when set, cant be adjusted and one that is used to control the flow. Like this:

 

[TBN]

Thanks Mottie. Having looked more closely both types of plastic heads are fitted. But the ones meant to be adjustable are very tight and don‘t want to turn.

 

[Madrab]

Thanks Mottie. Having looked more closely both types of plastic heads are fitted. But the ones meant to be adjustable are very tight and don‘t want to turn.

Old lockshield valves that haven't been used for a long time will tighten up, it's just the ay they are, even the new ones can be quite stiff. They're not meant to be used very much anyway. If you want adjustable valves that's why TRV's are used. They should be used as part of a well designed radiator system

 

[TBN]

Thanks Madrab. Yes that is my plan to fit TRV’s but as per this post the old Rads are all fitted with 3/4 Union connectors with very tight pipe work. I was hoping to find a 1/2 Union connector (the type that use an Allen key method of fitting) which would give the close connection. But no joy so far. Personally I prefer Union connectors as it’s so much easier to remove rads. Failing that I will need to use olive connections but I still can’t see they will work without modifying the pipework or using shorter rads with extended tails.