Not only do repeat failures take away from the contractor’s profit margin, they also tarnish a company’s professional image. Finding the cause and repairing it not only keeps the customer happy, it keeps the contractor profitable.
There is a vast selection of refrigerants, and sometimes a technician has a choice in selecting a refrigerant for a particular system. Knowing some of the basic properties of refrigerants can assist a technician in making that selection.
Thinking in temperature in-stead of pressure can help make the crossover to a new refrigerant much easier. The next time you’re faced with determining the correct operating evaporator or condensing pressure, think in terms of temperature and then convert it to pressure.
Too often, compressors get replaced when an external component, such as a defective start relay, start capacitor, or overload, is the true cause. A technician must always check these components before condemning the compressor.
Measuring the evaporator’s superheat value is an important part of analyzing a system’s performance. If a lower-than-normal value is measured, too much refrigerant is entering the evaporator for the heat load. If a higher-than-normal value is measured, too little refrigerant is entering the evaporator for the heat load.