Hydrostatic testing a PM Research #2 boiler

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New Member
May 5, 2017
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Hi Folks.

I just purchased a completed PM Research # 2 boiler, that is new--never steamed.

The builder did an excellent job and sold it only because he is ill. It must have been hard to let it go after all the work he put in to it.

The builder claims that he hydrostatically tested it to 150 psi. I have no reason to not believe him, but for my own comfort I want to do it myself.

One question I have is, does the sight gauge and pressure gauge need to be removed prior to testing? I only ask as it looks like removing and reinstalling the sight gauge is fussy and time consuming.

Second question: Has anyone from Maryland bothered to get an inspection done on their boiler? I emailed the State of Maryland inspection folks about the requirement for a ASME safety valve, but two weeks have passed and they have not responded.....

Thanks in advance for your help

David Garrison
Gaithersburg, Md
Remove all the fittings and replace with threaded pulgs, you can't do it with the pressure gauge attached as they will (should) open well below the test pressure.

Once it passes the hydro test put all the fittings on and fire it up for a steam test, safety valve should blow at or just below working pressure and with a strong fire not allow boiler pressure to rise more than 10% above working pressure.

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