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Discuss What size is this rad/valve connection? picture included in the Central Heating Forum area at UKPlumbersForums.co.uk.

  1. StuartP

    StuartP New Member

    Hi all.

    I'm removing the rad in the picture for decorating and want to blank off the connection from the thermostat/valve to the rad (will do both ends obviously). The thermostat/valve has 1/2 bsp stamped on it but pretty sure the connection to the rad is not 1/2 bsp, I have a couple of 1/2 bsp blanking caps but these are too small. Does anyone know what size the connection to the rad is?

    Many thanks in advance.
    Stuart

    IMG_1084.JPG
     
  2. heliotrope

    heliotrope Plumber GSR

    I would say that is 1/2 inch.

    How do you know that what you have is too small, have you tried to
    fit it?
     
  3. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    It is 1/2"
     
  4. StuartP

    StuartP New Member

    I haven't tried to fit it yet but the 1/2 bsp fitting I have looks way too small when offered up against what you see in the picture. Spanner size is also smaller on the 1/2 bsp fitting I have.
     
  5. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    this is what you need

    15mm

    the 1/2 refers to the connection to the pipe
     
    • Useful Useful x 1
  6. StuartP

    StuartP New Member

    Many thanks Shaun. I figured that that was the case but had no way of sizing the connection. I'll get a couple before taking the rad off. Thanks again, Stuart
     
  7. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    note that wont work for the pipe end if your removing the trv
     
  8. StuartP

    StuartP New Member

    I'm not removing the trv at this point, just need the rad off for plastering and paint. Cheers again
     
  9. Allgoode

    Allgoode GSR

    That trv & lockshield will be quite a few years old so may have a bit of a seep especially the TRV head side.

    Also that TRV variant only closes to the frost-guard (4 degree's approx) setting unlike the newer variants which goes to full shut-off, something to bear in mind at this time of year.

    Some towels around bottom of pipes are also a good idea if carpet is fitted to stop potential staining.

    Good luck,

    Andy
     
  10. StuartP

    StuartP New Member

    Ok, so I've bought a couple of the blanking nuts that Shaun kindly gave the link for but these are too small as well. I've not actually tried to fit them but when you offer them up they look way too small. Could the rad connection be 22mm? As you can see in the pic the pipe work is 15mm but I'm clutching at straws here a bit. Plasterer coming on Monday and I need this rad off and the connections blanked. Any thoughts anyone?

    Many thanks in advance
    Stuart
     
  11. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    It should fit as it's a standard 15mm nut and olive
     
  12. StuartP

    StuartP New Member

    I hear what you're saying Shaun but they're too small. Just to clarify, I'm talking about the connection/union between the trv and rad. Given that the trv is deffo 1/2 bsp as it's stamped on it, shouldn't the union also be imperial and not metric. The union is obviously bigger than 1/2 bsp, so could it be 3/4 bsp?
     
  13. Harvest Fields

    Harvest Fields Trusted Plumber GSR Top Contributor!!

    Surely the cap that Shaun is in about screws straight onto the valve not the tail for the radiator?
     
  14. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Correct

    If it's the tail end you want op it's a 1/2 cap you need
     
    • Agree Agree x 1
  15. StuartP

    StuartP New Member

    But I've already tried 1/2 and it's too small. Could the union be 3/4 bsp?
     
  16. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    On the parts what's inside the rad ? And defo won't be
     
  17. StuartP

    StuartP New Member

    It's the union between the rad tail and the trv that I'm talking about
     
  18. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Yea have you tried my nut yet ?
     
    • Funny Funny x 1
  19. Harvest Fields

    Harvest Fields Trusted Plumber GSR Top Contributor!!

    There are so many things wrong with that sentence that I am going to leave it there.
     
    • Funny Funny x 1
  20. StuartP

    StuartP New Member

    Not physically tried, only offered it up
     
  21. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    Take the rad off and the nut will slide off the tail, (the bit in the rad)
    Once you have the nut, put a 5p inside it and then a 1/2" tap washer and use that!
    That's what I always do and it never fails.

    finger tight will do, maybe a 1/8th nip, I always open the valve to make sure it doesn't leak.
     
  22. Harvest Fields

    Harvest Fields Trusted Plumber GSR Top Contributor!!

    So your the one:p:p:p:p
     
  23. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    AYE !
     
  24. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    Are you the one who owes me £100 in 5p's and £50 in Washers?
     
    • Funny Funny x 1
  25. Chuck

    Chuck Active Member

    And invoice as:

    Install 5p coin as blanking disc; parts: 50p, labour: £3.

    I assume ? The look on the customer's face when they read it must be priceless!
     
    • Funny Funny x 1
  26. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    It's the knowledge, skill and experience they pay for chuck!
     
    • Like Like x 1
    • Funny Funny x 1
  27. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    I prefer:-
    Provide and install Coin of the Realm depicting a portrait of Queen Elizabeth the second. The coin is professionally set upon a Black Vacca washer which is artistically embossed with the words '1/2" Vacca'
     
    • Funny Funny x 1
  28. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    That's got to be worth £100
     
    • Funny Funny x 1
  29. Best

    Best Trusted Plumber Top Contributor!!

    Maybe that valve has the large flange tail?
    Was more common on the older TRVs and on the valves with option for copper or iron pipe, which that is.
    The photo is difficult to judge, but the more I look at it, the more I am sure that tail nut is the large type.
     
  30. Best

    Best Trusted Plumber Top Contributor!!

    You really should always do all your work to a gold standard and use a gold half sovereign.
    Expensive, but it will always impress the person that removes the blanking nut.
    ;)
     
    • Funny Funny x 1
  31. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    I agree. It is the older type TRV with a 1/2" female thread on the bottom that you could use with the male nut and a longer than standard olive provided or any other male BSP 1/2" thread.
     
  32. Best

    Best Trusted Plumber Top Contributor!!

    So do you think the tail is the large nut type?
    I carry the large tails with a female fitting on them for draining from radiator valves or blanking off radiator valves that are the larger type
     
  33. Last Plumber

    Last Plumber Plumber GSR Top Contributor!!

    Yes. I think the nut is the older thick walled one. The tails as I remember had threads that were cut across if you know what I mean. I used to look at them and wonder why. Do you know what I mean or will I need to find one and post a pic?
     
  34. Best

    Best Trusted Plumber Top Contributor!!

    Do you mean the fine cuts across the threads that I think were done for to allow the tape, or thread seal to grip and stay in place?
    I think Westherm did similar valve.
    Also Tower might have been similar
     
  35. StuartP

    StuartP New Member

    So...are we any closer to getting a definitive size for this union. I'm leaning to it being 3/4 bsp. The trv is deffo 1/2 and the union is deffo bigger than 1/2 as I've tried a 1/2 nut against it and it's way smaller. I can't see it being metric size, what with the trv being imperial. Anyone agreeing with me on this??
     
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