A resistance reading of infinity across the "R" terminal and "S" terminal of a compressor motor indicates what?

A resistance reading of infinity across the "R" terminal and "S" terminal of a compressor motor is indicative of an open motor winding. In electrical terms, an "open" condition means that there is a break in the circuit, preventing current from flowing through that section. When testing motor windings, a reading of infinity suggests that there is no continuity between the terminals, confirming that the winding is not complete.

This situation typically arises when there is a physical break in the wire or winding insulation failure, which can prevent the motor from operating altogether. It's important for technicians to recognize this condition, as it indicates that the compressor motor is unable to function and would likely need to be repaired or replaced for the heat pump system to operate efficiently.