Looking around at the local home improvement center for a water pressure gauge, and all they seem to have is a gauge with 3/4" FGHT (Female Garden Hose Thread). Of course I could get a bunch of adapters (3/4" MGHT x 3/4" MPT -> 3/4" FPT x 1/2" FPT -> 1/2" MPT x 1/4" FPT), but I'd rather not.
The only other gauge I can find, is a 1/4" MPT gauge in the air compressor section of the store. Specifically a Husky 2 in. Heavy-Duty Side-Mount Gauge.
This gauge is exactly what I'm looking for, except that it's designed to work with compressed air.
Would there be a problem using this gauge designed for compressed air, to measure water pressure?
Best Answer
Pressure gauges commonly use a Bourdon tube. Bourdon tubes are a coiled metal tube and as the pressure increases, it forces the coil straight which then moves the needle. (think blowing a party horn, which causes it to unroll) The type of fluid (water/air) makes no difference to the tube, only the pressure exerted against the tube does. And since most of the tubes are made from bronze, copper or stainless water will not corrode it any faster than moist air from the compressor.
In all said, the air compressor gauge will most likely work without any issues.
But if you really want to get a water gauge, go to a pool supply store. They have pressure gauges for filters that are designed for water and use a 1/4 npt. They also have a nifty little ring on the outside where you can mark your normal pressure so it is easy to see if your pressure is low or high.