Yet for all their low cost, these devices are essential pieces of equipment for your air compressor.
Your typical air compressors come with two gauges. One is to indicate the air pressure that is in the compressor tank, showing the compressed air pressure level generated by the pump and also the decreasing pressure level in the air tank as you use the compressed air. The other air gauge indicates the pressure setting of the air regulator, and this pressure setting is the pressure that the downstream application will receive.
Description Of Air Gauges
The compressed air gauge will have a face, under a plastic shield on which pressure levels are printed. A needle is attached to a shaft protruding through the face, and that needle is calibrated to rotate to the pressure that the gauge internals are experiencing.
Air Gauge Video Overview
While there are a wide range of face diameters available, most of the lower end, general purpose gauges will have a face diameters of 1 1/2" or 2".
There are a number of ways to plumb the compressor air gauge. The most common is to have a male threaded fitting either on the back or the bottom of the gauge.
The operation of the air gauge will not be affected regardless of the mounting position. The two configurations are available to allow the user to pick the one that best suits their application.
Air Gauge Readings
Air gauges are built for the application.
For the air compressor, gauges will offer a pressure range from zero up to around 200 PSI.
Don't worry if yours doesn't show that pressure range. The air gauge pressure range on your compressor has been selected to indicate the pressure range that your compressor will require.
What Happens To Them
Many (most?) of the air gauges on smaller, home type air compressors are not of particularly great quality.
Over time, the needle may break, the needle shaft might fail, the plastic cover may get broken, or more likely, very humid air has, over often a short while, corroded the gauge internals to the point that it doesn't work anymore.
Air gauges are pretty important to the safe operation of your air compressor, and to ensure that your downstream tools and applications get the correct operating pressure.
If the tank gauge fails, you won't be able to see the cut out or cut in pressure levels, and you want to know this in the event that you have to replace a compressor pressure switch.
When you go to get another gauge, take the old one with you. That will ensure that you match the mounting thread, and enable you to select a gauge with the same, or similar, pressure range.
Air gauges shouldn't set you back more than $10-$15 for a general purpose type. If you select a stainless steel gauge, or one with different characteristics, it might be more. For the home compressor user, stick with the basic unit.
""Bill, you were right, when replacing the valve plate I had inverted it. I removed the head this morning and corrected the position of the valve plate. It seems to be working just fine now. Thanks a lot."