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Anti-sieze on union nut and various bolts?

seized123
seized123 Member Posts: 415
edited November 18 in Plumbing

Anyone use anti-seize compound on the nut part of unions, which doesn’t have to have a seal? Also on other stuff like flange and burner bolts? After battling the 25-30 year old 1-1/2 inch seized union from hell which I thought was going to stop me in my tracks I want to put that stuff on everything.

Comments

  • mattmia2
    mattmia2 Member Posts: 10,820

    I'd put it on bolts for things like tankless coils. Teflon pipe dope should do it for fittings.

  • mattmia2
    mattmia2 Member Posts: 10,820

    Pipe dope is a bit less messy, antiseize will make you look like the tin man.

    apexmech
  • seized123
    seized123 Member Posts: 415


    So @mattmia2 are you saying you use ant-sieze lubricant like in the photos for bolts, or do you just use pipe dope for those? I want to use whatever has the best ant-sieze properties regardless of looks. I never want to wrangle another coupling or bolt like I had to wrangle that union.

  • mattmia2
    mattmia2 Member Posts: 10,820

    The anti seize is good for more extreme conditions. Teflon pipe dope does a good job in most applications unless there is heat or weather involved. Dope doesn't smear all over everything as much as antiseize.

  • seized123
    seized123 Member Posts: 415
    edited November 18

    @EBEBRATT-Ed those are excellent tips, and I’ll get the ant-sieze.
    I tried the two hammer trick last night and it didn’t loosen to where I could get it the regular way, but it might have helped in the end.
    I was going to try heat (can you even heat up a 1-//2 inch union nut enough to help?) but went to a different way which absolutely saved the day. I’ll put photos below, but let me say first that as you’ll see I could have just cut just above the union where there’s copper to get the union out (which isn’t going to be reused), but then I’d have to deal with 1-1/2 inch copper which seems a bit hard to get except in 10’ lengths for like $120 which is a bit steep for a couple inches, Supplyhouse was out of short lengths. But really it was mainly pigheadedness. I banged on it with hammers and put the 24” pipe wrench on it and banged that and did the scissors thing with that wrench and a regular pipe wrench with a pipe on the handle. It’s quite possible if I REALLY strained it would budge, I have had that experience, but this wasn’t horizontal so I could put my weight on it and it just felt if I pushed too hard I could just pull something, muscle, tendon, earlobe. So I went to Plan C which worked like a charm. A couple pulls on the ratchet and she moved like a (slow) racehorse. This is my new go to technique for stubborn stuff that you can use the scissors method with. I’m sure it’s done out there but I never heard of it and it saved the day.

    ethicalpauldelcrossvMikeAmann
  • I use anti-sieze on burner door bolts, mostly on Viessmann boilers.

    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • GroundUp
    GroundUp Member Posts: 2,085

    Anti seize was common practice on anything steam or chilled water that was to be taken apart when I was in the pipefitters union. Hot water, gas, oil, etc I never found it to be anything but a mess- especially when the last guy dipped the bolts in the tub rather than using the brush to apply it only where the nut remained during service. With that said, I did come in contact with a 2" galvanized union on a hot water system last year that gave me a heck of a beating. Not enough room for long cheaters so I ratchet strapped a 2ft chunk of unistrut to a 24" wrench and then ratchet strapped the unistrut to the stairs across the room with another 24" wrench wedged against the block wall. I broke a 2 week old Milwaukee aluminum wrench and threw my neck out of place in the process, but I got it loose. I do wish somebody would have used anti seize on that particular joint

    Alan (California Radiant) Forbes
  • seized123
    seized123 Member Posts: 415

    @GroundUp ratchet straps are my new solution for almost every problem.

    delcrossvGroundUp
  • mattmia2
    mattmia2 Member Posts: 10,820

    Could've cut the union or the nipple out of the boiler and unscrewed the union from the copper. Better hardware stores and some supply houses will sell cut pieces of larger diameter copper.

  • retiredguy
    retiredguy Member Posts: 974
    edited November 19

    I worked on high and low pressure steam my whole career so I don't have to say anything since @EBEBRATT-Ed said it all. I agree with him 100%. Also, try this, loosen the upper pipe wrench so it does not bind the union nut making it harder to turn that nut and use a penetrating oil several times a day and let it set overnight to enter the joint.

    MikeAmann
  • seized123
    seized123 Member Posts: 415
    edited November 19

    @mattmia2 yup, cutting was an option. I could have cut the black pipe nipple down below the union and hoped to have better luck unscrewing the whole union off of the copper sweat x male NPT adaptor which is visible just above the union in the first photo (and from which, after I had successfully unscrewed the union nut, the female part of the union did screw off smoothly). Another option was to cut the copper above that copper adaptor and voila!, boiler would be loose from supply riser. But the problem with that is, as you can see from the photo, there's just an itty bitty tiny nipple of 1-1/2 copper between the adaptor and the tee above it that leads to the whole conglomeration of zone valves etc. I would have to make the cut into that nipple, seems to me. Then to connect more riser piping down below to the new boiler I'd have to unsolder what would be left of that nipple (very little) and I shudder at any thought of unsoldering anything, having had a few experiences where something absolutely positively refused to come unstuck. This fear of unsoldering anything was intensified with my next experience in this drama of DIYer vs. Pipe, which I will describe briefly below for those who, after reading what I just wrote, would like a second headache on top of the first.

    So, union is off, old boiler is out, new one up on blocks (but only one set of blocks instead of the old four, to make space for a circulator on the supply where there was none before due to some good advice from @EdTheHeaterMan). I line up the supply nipple out of top of boiler with what's hanging down from manifold visually as well as I can … (Footnote. It was not easy lining up this boiler precisely so the new near boiler piping will line up with the risers, and I'm not sure it's even right yet. The thing is 600 lbs., and does not want to be twisted and walked delicately this way and that when its on cinder blocks whose footprint is barely bigger than the boiler's. I do not know how you guys do this stuff, day in, day out. I'm in awe, no exaggeration.)

    Anyway, now I'm lined up, within reason, and I start trying to dry fit, in order going up from the boiler: circulator with flanges, nipple, coupler to existing male npt copper adaptor. But the coupler won't screw onto the adaptor, I tried 800 times, I figure the adaptor's cross threaded or has some other thread-related personality disorder. Tried other 1-1/2 fittings in case it was the new coupler's fault, but nothing went on. So I figured I had to unsolder the adaptor and replace it with a new one which, in an unusual fit of brains, I had ordered just in case. But this would mean facing my greatest fear, unsoldering. And sure enough, the damn thing wouldn't budge. I had the torch on it for-absolutely-ever (which I hate, I feel like I'm damaging something nearby, like the ball valves and zone valves located just upward of this fitting I'm trying to remove, or inadvertently unsoldering everything else in the system). YouTube told me that almost always the culprit in these situations is water. This is a vertical riser and although the system is drained and the ball valves closed I still saw drips during the day. So now I waited until it cooled and went up with a paper towel which came out dry, plus I figured that any moisture in that manifold between this fitting and the closed valves would have evaporated. So I tried again but nothing. So anyway in the end I took the female part of the old union which had been on this adaptor and attempted yet again to get it threaded on evenly, and then it did seem to go (with a lot of resistance) so I wrenched it on tight figuring maybe I'm retraining errant threads to be legitimate again. And after that the coupler did seem to go on untilted and evenly, so maybe I'm okay (even though defeated by the unsoldering episode).

    My plan of hoping that the distance between the circulator on top of the boiler and the copper manifold (which does have a tiny bit of play up and down) can be matched by a standard black iron pipe nipple may be foiled, but I'm hopeful; I bought a bunch of short iron nipples in various lengths. If not, @mattmia2, I did locate a hardware store that will cut a piece of 1-1/2 for me (I now love that hardware store) and I guess I could do something like this, going downwards: copper female x sweat adapter screwed onto that sweat x male adapter that I can't get off, then short copper nipple cut to length, then sweat x male npt into the top flange of the circulator. That's IF I can get the female copper adaptor onto the weird threads of the old male one.

    BTW, someone please reassure me that my applying the torch to the adaptor for more time than four Avengers sequels plus Gone with the Wind did not necessarily harm the five ball valves and then five zone valves that are just above it in the manifold.

  • mattmia2
    mattmia2 Member Posts: 10,820

    The ball valves are far enough away that they shouldn't have got hot enough to be a problem. If you are right at the valve you can get it hot enough to melt the teflon seats.

    The tubing in the fitting cab be a tight fit and that can be very hard to pull apart with just a pair of channelocks or something. You also frequently heat it far above the temp where the solder melts and start to soften the copper or even start to weld the copper. If you cut or file a slot in the fitting just enough to get to the solder then heat it again it should be much easier to get off because you will have released the tension holding it on the fitting, but I would just use an adapter unless the threads are trashed. You could also do the manifold in black iron which is likely to be cheaper than copper and actually a little easier if you measure right. I'm not sure that boiler really needs 1.5" to move all the heat it can produce. Is it connected to an old gravity system or a monflo system?

    If the threads are damaged it should be evident by looking closely at them.

    We could write another 10 page thread on desoldering fittings.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 9,269
    edited November 19

    did you try putting a 1-1/2" circulator flange on the Copper Male Adaptor?

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    mattmia2
  • seized123
    seized123 Member Posts: 415
    edited November 20

    For some reason I put the circulator right on top of the first supply nipple; and the coupling, which finally went on evenly, on the adapter. Went from 4 levels of blocks under the boiler to one to accommodate the circulator, following your suggestion @EdTheHeaterMan. To my mind that sure beats raising the manifold with at least five cutouts and five solder joints on a ladder, with a possible water drip problem.

    Below are photos of where things are so far. Obviously the return final connection has to be made, soldering 1-1/4 to 1-1/4. I’m a bit nervous about that because of possible water on that side like on the other side. I closed all five ball valves thinking that would ease dripping. But then saw on YouTube that steam pressure in the pipes from water can seep into your joint and prevent soldering. This made me wonder if it might be better to open one or more valves so much of that pressure could escape up into the miles of pipe through the baseboards. Sounds like overthinking, but I actually think it’s a good question given how often this problem with water and soldering pops up. Any thoughts?

    EdTheHeaterMan
  • mattmia2
    mattmia2 Member Posts: 10,820

    Shake the return around a few times long before you try to solder it to shake any water loose. If you're going to pull the end down some when you join it, do that a few times well beforehand and leave it that way for a while because that usually will loosen up some water somewhere.

    You want the part you're soldering open to the atmosphere somewhere, could be a boiler drain or the relief valve or something, just don't want the air in the pipe to build pressure as it is heated and bubble through your joint.

    delcrossv
  • seized123
    seized123 Member Posts: 415

    @mattmia2 great advice. I will be shaking the pipe it as soon as I stop typing.
    The relief valve isn’t on yet so I’ll leave that open and maybe open the drain too.

  • mattmia2
    mattmia2 Member Posts: 10,820

    The relief tapping is more than enough, just need to not be sealed. Even cracking a union or flange open is enough.

  • seized123
    seized123 Member Posts: 415

    @mattmia2 I forgot there’s a wide open tee just under the stretch if copper, so lots of ventilation.

    Anyway it went well, the solder acted like it’s supposed to act. I shook the pipe like you said and shook some other things just to be safe and I even shook a wrench at the pipe, you know, like to show who’s boss, and I think all of those things worked but mostly shaking the pipe and having ventilation.

    delcrossvEdTheHeaterMan
  • JUGHNE
    JUGHNE Member Posts: 11,266

    Am I remembering correctly that if flux is applied as the fittings are heated, that the unsoldering will work easier??

  • delcrossv
    delcrossv Member Posts: 1,288

    I have not found that to be the case as the flux can't get into the joint. Heat and twist.

    Trying to squeeze the best out of a Weil-McLain JB-5 running a 1912 1 pipe system.
  • pecmsg
    pecmsg Member Posts: 5,271
    edited November 20
  • JUGHNE
    JUGHNE Member Posts: 11,266

    On a failed solder joint that didn't take, the flux applied right at the fitting seems to get into the joint for resoldering.

    Yes, I admit to some bad joints over 40+ years.

  • mattmia2
    mattmia2 Member Posts: 10,820

    the flux will flow in if there is a gap for it to get in there.

    delcrossv
  • JUGHNE
    JUGHNE Member Posts: 11,266

    Heating the socket loosens existing solder and the flux could then be drawn in.

    This has worked on existing good joints and for fixing bad ones.

  • HomerJSmith
    HomerJSmith Member Posts: 2,628
    edited November 30

    I use anti-seize on everything, lug bolts on car wheels, etc.

  • HomerJSmith
    HomerJSmith Member Posts: 2,628

    @JUGHNE The only bad joint that I'll admit to is my left knee. Good Tip!

  • MikeAmann
    MikeAmann Member Posts: 1,067

    Apply anti-seize to your circulator bolts. Since the system is now filled and has pressure, use vise grips on either side of each bolt (clamp the flanges together) before removing.