HVAC Systems · Electrical Components
Fan/Switching Relay
A low-voltage-controlled relay that switches a higher-current load — most commonly the indoor blower — on and off in response to the thermostat or control board.
Common uses
Switching the blower motor, isolating control from load circuits
Common symptoms
- Blower will not run
- Blower runs continuously
- Chattering relay
Common repairs
- Relay replacement
- Contact inspection
- Coil voltage check
Related terms
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