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How To Flush Out Debris from Governale-type Rad Before Pressure Test

D107 Member Posts: 1,785
Got my 8 section OCS with its 1.25" input/output, and have the necessary bushings etc to connect one end to pressure gauge and the other to garden hose. Before I pressure test, I wanted to flush out some rattling debris inside the rad.

Plumbing supplier said don't use teflon on the bushings into the rad since somehow that could allow too much pressure and burst the rad--said to use pipe dope. Without him saying that I probably would have used telfon since I'm looking for a very temporary connection. Anyway he also said no need to test to 30 psi, since heating usually only goes to around 15. I know that, but when they do a boiler pressure test, or somethiing malfunctions, won't pressure reach 30? Or is he hoping the rad isn't crap and bursts and then has to replace it since I bought it there?

Anyway I thought I'd first fill up the rad to about 10psi then remove the pressure gauge end bushing and then keep the hose on and flush it out. Make sense?


  • mattmia2
    mattmia2 Member Posts: 4,282
    What is it rated for by its manufacturer? Teflon tape (or dope for that matter) can lubricate the threads and make the taper screw in further and exert more force on the casting if you keep cranking on it, that is what they mean by pressure.
  • D107
    D107 Member Posts: 1,785
    edited September 2020
    @mattmia2 So it doesn't really matter if I use teflon tape, just don't crank it too much. Of course I have no idea how much is too much but I guess I'll err on the conservative side.
  • Canucker
    Canucker Member Posts: 704
    Just turn it until it seals @D107 No need to make it a feat of strength to undo. I would test it at 30 psi for the exact reason you mention
    You can have it good, fast or cheap. Pick two