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Hot water coil gasket

bob young
bob young Member Posts: 2,177


  • bovide_4
    bovide_4 Member Posts: 161

    What is the best gasket to use for a hot water coil plate on a large boiler?
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    ARE YOU KIDDING ME, RAINBOW?? that has to be the worst crap around definetly not meant for that application --order a black rubber gasket from your supply house or look into heat exchanger manufacturers like --- Diversified Berdell in LONG ISLAND city ----RIDGEWOOD NY. they custom make ALL brands of heat exchangers on site /// and ALL of them come with a black rubber EPDM gasket-----(Diversified Heat Transfer Products inc.)
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    if you are going to change the gasket a word of warning to you --there are 2 other gaskets that need to be replaced on the inside of the coil plate where the inlet and outlet meet the plate --also if its been leaking for a while the studs are rotted and will break -(very common)-you may need to have a coil plate welded --this is not a residential type job -- i just had to do 1 today actually a Lindy coil an F74-53 do --on an Eastmond FST 125 that we needed a coil plate welded on 39 faceplate///////////what boiler are you working on ??
  • No matter what

    type of gasket you use , the most important thing to do is make sure the bolts are easy to remove for next time . I haven't used it , but I've heard Never-Seize works well . Personally I wrap Teflon around the bolt threads and use washers . Seemed to work great on my own coil .
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    Ron honestly the gasket material matters More than the Never-Sieze --if your gasket material breaks down near the studs where they meet the coil plate --sure the neversieze and a wire wheel to clean the exposed threads will make it easy for the nut to come off --But the stud can be rotted from a 1/2 stud down to 1/4" or nothing -there will not be enough material to pull in the coil -- without breaking --(i'm talking about commercial)--- on a side note ALMOST EVERY nut,bolt i put anywhere gets Never-Sieze
  • I've taken out

    quite a few coiled boilers :) It don't matter the material , they all dry out from the outside and get brittle over time . Some boilers are better designed ( with more surface area around the coil bolts ) to hold off the drying gasket better than others though . I'll agree black gasket material lasts longer , but it will become brittle over time . And it won't matter what material you wound up using if the coil leaks near the studs .

    Weil Mclain has the best solution - the captured O - ring design for the coil . Now if they'd cast the boiler so the coil protrudes out some , so we could see a coil leak easier ..........
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    I absolutely agree --all gasket material that is widely available for coils will get brittle --the Black rubber holds up the Best and Longest ----NOw if this is a large commercial coil -in my experience i have found that coils that leak at the gasket -you also need to replace the other 2 gaskets on the in/out and i have had lots of occasions where the studs broke ,were too far gone or the gasketing surface is too pitted to seal --------- never,never NEVER-- EVER use RAINBOW PACKING for anything except an emergency ---i do have to clarify that the Smooth red rubber (that is used for flange gaskets is different than Rainbow,) Rainbow packing is the red rubber that has the texturing -
  • bob young
    bob young Member Posts: 2,177

    I have used red rubber rainbow packing more than a few times in the past 47 years i have been in the business & never had a problem with it. maybe you are not familiar with what i am refering to. it is especially helpful on a replacement or repair where the face of casting is semi-pitted or an unevan surface. good for flange unions & companion flanges also. in any case i was definitely not kidding. i take my craft extremely seriously. all gaskets eventually rot or wear. its the luck of the draw. nothing is forever. rainbow is a more than acceptable product.
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    THE RED rubber sheet with texturing is Rainbow , the smooth red rubber that you can buy for flanges that is pre-made --that type of rubber is different --BUt definetly not as good as the Black rubber EPDM gasketing --i have used -What I know of as Rainbow packing -before and have had the gasketing blow --out on condensate pumps, flanges etc.. (anything with higher temps.-) i haven't been in the business for 47 years but i do have 20 or so years experience -so far ---------------------------- EPDM black rubber gasketing Is the BEST readily available material for coil gaskets the question was what is the Best --
  • Radiator Ranger
    Radiator Ranger Member Posts: 81

    Gwen Healy - Radiator Ranger
  • billtwocase
    billtwocase Member Posts: 2,385

    Throw all the rubber gaskets in the trash where they belong, and use Teflon Redi-rope. If you want the best rubber, Gator is it. Check out Frederick Seal's site for these products. I've been using them for years, and they never fail. peace
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    thats funny ,i was thinking of the teflon flange gaskets and teflon gaskets for the Mcdonnel Miller low waters -as a much better material for the job but its not readily available and most people don't even know its out there , i use teflon gaskets on the high pressure flanges all the time , they last the longest they hold up to the heat and will seal a pitted uneven surface -and i use teflon on high pressure steam gage glass//thanks for the link ,i'm always looking for new ways to fix old problems/////////i checked their site and Gator is an EPDM black rubber
This discussion has been closed.