When troubleshooting a single-phase refrigeration compressor that will not start with the proper applied voltage, it’s important to determine the true cause. Too often, these compressors get replaced when they’re not really defective. Sometimes, 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.
Misdiagnosing a compressor can lead to losing a customer and a poor business reputation. Since replacing a compressor is an expensive repair, some customers will get a second quote from another contractor. If the second contractor inspects the system and finds the problem to be a defective start relay, start capacitor, or overload, the initial contractor will look as if they’re trying to deceive the customer intentionally, when, in fact, they may have simply misdiagnosed the problem and prepared the quote based on that assumption.