Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.

If you've found help here, check back in to let us know how everything worked out.
It's a great way to thank those who helped you.
Need to contact us? Visit

Angle steam radiator valve leaking

Hey guys, the top portion were the knob turns on my Angle steam radiator valve is leaking steam. I’ve seen someone unscrew the top of theirs once and apply some type of glue to stop the leak on theirs. Would this be the best route, which product would you recommend thanks!


  • If you can tighten the top nut a bit under the handle, that may compress the packing which makes the seal.If not then it may need to be repacked, so let us know how successful it was for more information.
    Your system may also be operating with too much pressure, and need advice for that.—NBC
  • gfrbrooklinegfrbrookline Member Posts: 610
    edited December 2019
    If tightening the nut does't work you can try repacking it with this product from Amazon, BrassCraft Mfg SF1336 Rope GRAPHITE TWIST PACKING 3/32X25 X 24 . I have had good luck with it. Back the bonnet nut off raise it up and wrap the stem 3 or for turns, tighten the bonnet back up and you should be good. Found the instructions on a youtube thread from This Old House.

    My local contractors are unwilling to repack a valve, they just want to replace them so they don't have a repeat call if it doesn't work. The problem I have recently discovered is when they replace the valve the feed pipe is going out of round so the new valve leaks from the bottom so they have to come back anyway.

    The picture I have attached is from a radiator valve that was replaced about 10 years ago and has probably been leaking since it was replaced. So the moral of story is there are advantages and disadvantages to both approaches.
  • mattmia2mattmia2 Member Posts: 1,318
    You can get string packing at virtually any hardware store.

    If they are crushing the pipe they are almost certainly using the pipe wrench improperly.
  • They may not have changed the spud at the same time as the valve.
    They all have different angles on the mating faces.—NBC
  • gfrbrooklinegfrbrookline Member Posts: 610
    @mattmia2 and @nicholas bonham-carter , Agreed on both statements. Unfortunately it is located in an apartment so it went unnoticed.
  • daveamirdaveamir Member Posts: 64
    Hey I compressed the nut on top with a wrench it’s wiorking for now thanks guys
  • daveamirdaveamir Member Posts: 64
    Hi guys it started to leak again can I use something like JB Weld I’m afraid I might unscrewing improperly I figured that might be safer
  • mattmia2mattmia2 Member Posts: 1,318
    No. unscrew the nut on the top, it should be relatively easy with a crescent wrench, add some string packing, a little at a time if a few turns aren't enough, you want the threads on the nut to catch well before you try to compress it with the nut. If that little bit isn't enough, you can unscrew the packing nut and add a little more. You shouldn't have to make it super tight to get a seal.

    If you put JB weld on it you at best will have to remove it to fix it properly and at worst will have to replace the valve which is much more difficult project than just adding some packing.
Sign In or Register to comment.


It looks like you're new here. If you want to get involved, click one of these buttons!