In this video, This Old House general contractor Tom Silva shows discusses what to look for when buying and operating an air compressor.
1. Most air compressors have two pressure gauges. One gauge shows the air pressure—measured in pounds per square inch (PSI)—stored in the tank. The second reveals the air pressure being delivered through the hose to the tool.
2. The second pressure gauge is fitted with a regulator, which lets you adjust the air pressure to match the recommended PSI rating on the tool.
3. Compressors have steel storage tanks to hold the compressed air. The larger the tank the more pressurized air the compressor can deliver.
4. When choosing an air compressor, it's also important to know its standard cubic feet per minute (SCFM) rating, which is the amount of air the unit can produce at a specified PSI.
5. High-volume tools, like paint sprayers require higher SCFM ratings, than a low-volume tool, such as a brad nailer.
6. An oil-less compressor requires no lubricating and is maintenance-free.
7. An oil-filled compressor must have its motor oil changed at least once a year.
8. At the end of each workday, open the spigot on the bottom of the tank to drain out any condensation.