AC system cycling too often.
unit will have a series of protective switches along with the thermostat to prevent system failures:
1. Low pressure switch to prevent system from reaching an extremely low vacuum. This condition is most often caused by low refrigerant volume.
2. High pressure switch is designed to stop compressor
before high pressures above 200 psi may reach an explosive value. Overly high refrigerant pressure is caused by poor water cooling
at condenser. Refrigerant Cooled down after passing through condenser on this unit should be less than 120 degrees F. Corrective action of both pressure switches would be to check refrigerant level at sight glass and feel temperature of refrigerant line leaving condenser.
thermo snap action switch mounted under a plastic cover on outside of compressor may be indicating excessive compressor temperature or it is just time to replace it.
4. Thermostat itself is the main normal control of compressor cycling. All thermostats on electrical
compressors have built in temperature control and over load protection by way of a time/pressure control between compressor shutdown and the next start up. If these compressor short cycle off and on too quickly compressor will overheat and be damaged, not to mention waste energy. The thermostat can also cause short cycling if its sensing tube is incorrectly installed.
In testing to find what is causing this short cycling problem DO NOT BYPASS THE HIGH PRESSURE SWITCH AS DAMAGING EXPLOSION WILL HAPPEN If pressure goes high enough. Closing start relay is dangerous if high pressure is the problem.