Service & TroubleshootingQuestion 84 of 110
A furnace that heats briefly then shuts off repeatedly before satisfying the thermostat is exhibiting what?
a.Normal operation
b.A refrigerant leak
c.Short cycling
d.High subcooling
Explanation
Short cycling is repeated brief on-off operation before the space reaches setpoint, often caused by an overheating limit trip, a dirty flame sensor, oversizing, or restricted airflow. It wastes energy and stresses components. Diagnosis targets airflow, the limit switch, and flame sensing.
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