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Is this vent CPVC?

Kestrel Member Posts: 102
This is a Lochinvar WHN085.  I purchased 2" CPVC to do the vent and air intake, and it's quite a different color than I expected.

The material I bought from the supply house is a light beige.  The vent on the boiler (pictured below behind the pressure relief valve) is a much darker gray.  Are they both CPVC?  

Unfortunately I realized this after hours on Friday, and I'm hoping not to have to wait until Lochinvar tech service opens on Monday!


  • Slimpickins
    Slimpickins Member Posts: 323
    wrong stuff

    Sounds like you got Cresline Flow Guard Gold which is smaller diameter than the gray CPVC. It's used for hot and cold water piping. I ordered CPVC from a supply house for will call and went to pick it up and thats what they had for me. I've learned since, you need to specify that you're using it for venting a boiler. 
  • Kestrel
    Kestrel Member Posts: 102

    I did - I did tell them exactly what it was for.

    Is there a specific designation for the darker gray stuff for flue venting?
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,837
    Check the ASTM numbers....

    In the installation manual, it clearly states the ASTM requirements and approval numbers for using different plastics. If the FlowGuard meets those standards, then it is safe to use. If not, return it and make sure they give you the right stuff. ALso make sure the primer and cements you use are also in compliance with the manufacturers requirements. Not all cements and or primers are the same.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • meplumber
    meplumber Member Posts: 678
    Flowguard does not meet the standard.

    As previously posted you need CPVC. I use Sch 80 CPVC. It is grey in color and meets the ASTM standard.
  • NYplumber
    NYplumber Member Posts: 503

    I wasnt aware there was a rating on glue and primer.

    Where on the glue does it state ASTM rating?
This discussion has been closed.