Gas Heat ESCO Practice Exam

A technician reads 0 ohms between the common and low speed wires on a 120 VAC furnace motor. What does this indicate?

1. Blower motor's normal operation

2. Normal winding resistance

3. Shorted winding

4. Winding continuity

The correct answer is: Shorted winding

When a technician reads 0 ohms between the common and low speed wires on a 120 VAC furnace motor, it indicates a shorted winding. This means that there is a direct connection (short circuit) between the common and low-speed windings of the motor. This condition can result in abnormal operation of the motor and may require repair or replacement to ensure proper functioning of the blower motor. The other options are incorrect because: - A: Just because the voltage is 0 ohms between the common and low-speed wires does not indicate normal operation of the blower motor. - B: This scenario does not relate to normal winding resistance, as 0 ohms signifies a shorted winding rather than typical resistance. - D: While winding continuity is essential for motor operation, a reading of 0 ohms does not signify winding continuity but rather a shorted winding.