EDITOR’S NOTE: This is part two of a two-part article on air conditioning system troubleshooting and commissioning. Part one, which ran on Page 25 of the March 7 issue of The NEWS, covered air- and refrigerant-flow problems, cooling coil size, condensers, subcooling, and low-condenser-entering air temperatures. This month’s article will cover liquid and suction line restrictions, undercharge and overcharge, inefficient compressors, and non-condensables in the system.
Diagnosing an air conditioning system isn’t easy. A service technician must be a trained professional to diagnose a system efficiently and correctly — no longer can a tech rely on rules of thumb for coil temperatures or pressures. So, if a tech encounters balky systems as he or she performs spring a/c system tuneups, here are some troubleshooting tips to help the professional diagnose and repair systems so customers remain cool all summer.