Replies

1. 
   Walt_Pollard | Mar 20, 2001 11:09pm | #1

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   I've used bushings to reduce the size of one of the inlets to 1/8th inch and then threaded in a pressure valve. I've then used bushings to reduce the other side to 3/4 and threaded in a hose bib (also called a boiler drain. You can then attach a garden hose to the hose bib and fill up the radiator. I pumped mine up untill they were at about 30 pounds of pressure and left them for a while. It worked pretty well. So far I have only blown a hole in one radiator...and that was before I added the pressure gauge. Be careful though....if you do blow one up if realy sends some metal flying....it is amazing what a mere 50 pounds of pressure will do! P.S. the one I blew up was in the basement....do this OUTSIDE.

1. 
   David_Thomas | Mar 21, 2001 08:41am | #2

   *IMPORTANT SAFETY TIP: When pressure testing something large like a radiator, use water NOT air. Even if you fill with water, you may be compressing air in the radiator. You should purge the air as you fill with water. The stored energy in compressed air can be huge. The stored energy in compressed water is tiny because a little bit of expansion relieves all pressure. This is most important in brittle materials like rigid plastic pipe (PVC and ABS) and cast iron. Maleable metals often deform without shattering, but it is still safer to hydrotest, not air test. It is also more sensitive to small leaks. Try to keep the temperature constant (let the cold water come to temp before topping off and sealing it). It eliminates one confounding factor. -David

2. 
   robert_lightfoot | Mar 21, 2001 08:41am | #3

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   My home is heated by water radiators. I have a few that are very decorative. I would like to test these radiators for leaks prior to reinstalling them. Is there a proven technique a novice can use to test these radiators for cracks or leaks. A plumber told me to use a flashlight--if you see any rusty looking drip marks these are possibly cracks. There has got to be a better way to test for cracks or leaks. I would think rusty looking drip marks could come from something other than cracks or leaks. If there is a leak in the radiator, will STOP LEAK close it? Any advice would be greatly appreciated.Thanks.