Auto Air Conditioning Safety Switches: Cheap Insurance
We should stop here and mention system protection switches. A “high pressure safety switch” disengages the compressor clutch on the compressor if internal pressure exceeds safe limits (406 psi) and then re-engages the compressor clutch when the pressure is back down within acceptable limits. A “low pressure switch” disengages the compressor clutch if there is excessive refrigerant loss (below 30 PSI). A “Binary Switch” incorporates both of these protections into one switch. A “Trinary Switch” incorporates both high and low pressure cutoffs, plus adds an “electric fan engagement signal” (at 254 PSI) feature to help bring internal temperatures down. These switches are great insurance on any system, and should ALWAYS be incorporated. See Safety Switches.