What reading would a technician expect between the high and low speed wires on a 120 VAC furnace motor if the winding is open?

When assessing the condition of a furnace motor, particularly concerning the high and low-speed windings, it is crucial to understand that an open winding indicates a break in the electrical circuit. In this scenario, if the winding is open, that means there is no continuous path for current to flow through that winding.

When a technician measures between the high and low-speed wires and finds that the reading is open, it signifies that there is an interruption in the circuit, confirming that the motor's winding is not functional. This is consistent with the definition of an open circuit, where continuity is absent due to a break. This condition typically requires repair or motor replacement, as it indicates a failure in the winding that prevents the motor from operating correctly.

Thus, the expectation of an open reading between the high and low-speed wires is indeed accurate, reflecting a non-operational winding.