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Is this asbestos? Plus a question about the king valve.

pcolburn2 Member Posts: 25
Is the dark material on the main steam shutoff asbestos?

Also, I’m open for suggestions as to how to deal with the shutoff valve.
It appears to be pinhole leaking from where the bolted elements come together.
Should it be in kind replaced, high heat expoxy sealed or replaced with mains without a shutoff?

This is a one pipe system single boiler system servicing a multi unit building.


  • mattmia2
    mattmia2 Member Posts: 9,670
    edited March 2022
    You can replace the gasket between the flanges to fix the leak. The substance looks like some sort of mud covered with undercoating or something to glue it together. Only way to tell if it is asbestos is to test it.

    That ceiling material should be tested as well.
  • retiredguy
    retiredguy Member Posts: 907
    As @mattmia2 said, the gasket between the flanges can be re[laced but the valve will probably have to be removed to allow for access to the gasket material and the flanges. The gasket will not just slide out to be replaced and the metal gasket surfaces on the flanges and valve will have to be cleaned. This is not a job for a novice or untrained since that valve is heavy and the gasket is usually tough to remove. One more thing, if the steam has leaked for a long time the metal surfaces of the valve and flanges may need to be resurfaced or if they are too badly damaged they may need to be replaced. If I were you I would call a service company to do the work but in my case I was the one that would be called. As far as the question of that material being asbestos, have it tested to be sure.
  • JohnNY
    JohnNY Member Posts: 3,231
    Is this Brooklyn?
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
  • pecmsg
    pecmsg Member Posts: 4,861
    The only way to know is to take samples and have it analyzed. I agree the ceiling needs to be tested as well.
  • AdmiralYoda
    AdmiralYoda Member Posts: 629
    edited March 2022
    I'd have that stuff tested. Maybe a couple of samples, one of whatever is on the ceiling and one with whatever is on the pipe.

    Is it hard as a rock or soft and spongy?

    I almost wonder if there was a steam leak and someone put some JB-Weld type substance on it to try and fix the leak, and that stuff on the ceiling is a type of paint to cover up damage from the steam leak.

    I've done a couple tests in the past....not sure who I used but I think I got the kits through Amazon. Results were in 5 days with a certificate. I think I paid extra for overnight testing too.
    EBEBRATT-Ed Member Posts: 15,544
    edited March 2022
    Most likely it is asbestos. I would just chop the old valve out and put a short pipe in it's place unless your local code requires a stop valve

    The easiest way to remove/replace that valve is to remove the bolts holding the valve bonnet and pull that out first. Much less weight to deal with
  • Intplm.
    Intplm. Member Posts: 1,967
    edited March 2022
    Have the material on the valve tested. And while you are at it, the ceiling material tested for asbestos. Asbestos is usually not a problem unless it is disturbed ["fryable" ]

    The valve can be removed and or replaced. New gaskets will repair the leak.
  • dopey27177
    dopey27177 Member Posts: 887
    If you have asbestos it can be removed by the glove and bag method.

    The valve does not need to be removed to clean the out the old gasket.
    The bolts can be removed and the valve allowed to roll down on the one bolt on the bottom of the flanges.

    The safest way to do this is to pull the bonnet out of the valve, that takes a lot of weight off the valve body.
    The replacement gasket for the bonnet can be made from 1/8" thick Monico graphite gasket material.

    This job is a tweo man job. (two men is for safe working conditions)

  • mattmia2
    mattmia2 Member Posts: 9,670
    The gaskets may also be asbestos