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Combustion analysis

bguthrie Member Posts: 1
Is there any approved or quality method of sealing a drilled hole in PVC for a combustion analysis test on a condensing appliance? I find a lot of them with foil tape, duct tape, and some just left open and this is a positive pressure vent.


  • PVC test hole

    I usually drill & tap (for 1/4" NPT), do my analysis, then install a SS solid core pipe plug.
  • Tim McElwain
    Tim McElwain Member Posts: 4,593
    Dave is correct

    just add a little RTV high temp sealant to the bolt threads. Our inspectors around here accept that. It is actually best to do it in an elbow ahead of time then just tap the PVC after it is inserted into the elbow and glued.
  • SpeyFitter
    SpeyFitter Member Posts: 422
    IPEX's Approved way.

    Basically just a bushing & a plug: http://www.ipexinc.com/Content/Products/Product.aspx?IsDownload=true&FileId=1301
    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
  • Empire_2
    Empire_2 Member Posts: 2,343
    Me too:

    I use 1/4" tap.  I have a nice tap set that you can purchase almost anywhere.  This fitting will never accidentally pop out.
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