To check the condition of the compressor's motor windings, a technician will need to measure the resistance of the windings using:

• A. A standard ohmmeter
• B. A voltmeter
• C. An ammeter
• D. A manometer

Answer: (A)

Testing the winding condition comes from checking continuity and reading the actual resistance of the windings. An ohmmeter is designed to apply a small current and measure resistance, which lets you see if a winding is open, shorted, or has abnormal values compared to the manufacturer’s cold-winding spec. For a compressor motor, you’d disconnect power and measure between the relevant winding leads (and sometimes to ground) to verify that the run and start windings each show a proper, finite resistance and that there isn’t an unexpected short between windings. A voltmeter only measures voltage, not resistance; an ammeter measures current draw but doesn’t directly reveal winding integrity; a manometer measures refrigerant pressure, which is unrelated to electrical winding health. That’s why the standard ohmmeter is the appropriate tool.