The high-side pressure is related to the ambient air temperature. When servicing a unit with the condenser inside an air-conditioned building, expect the head pressure…

There are several types of refrigerant with different qualities and boiling points. These different boiling points affect pressures in the evaporator and the condenser coils.…

The formation of a puddle of water under the refrigeration unit is a very common problem. In figure 85, note that the suction line going…

The moisture drain tube to the water evaporator pan may become plugged with debris and gummy substances. When that happens, water created in the defrost…

Residential units with freezers cause trouble when there is a puncture in the inside or outside wall of the unit through which air penetrates the…

1. Connect piercing valves (if there are no access valves in the system) and discharge the system leaving the valve open. 2. Clean the puncture…

When lower-than-normal pressures are observed on both the high and low sides and the system does not cool properly, look for a refrigerant leak. This…

This method is widely used in commercial refrigeration since the exact back-pressure requirement is known. (This is explained in “Saturated Vapor Refrigerant Pressure and Temperature…

This method of charging is used where the evaporator can be readily seen, such as in manual-defrost units, cycle-defrost units, and most commercial units where…

a. Check the nameplate on the unit to determine the exact amount of charge. This figure is reflected in ounces. (Some larger commercial units indicate…