Air conditioners are supposed to hum. New or louder sounds are the system telling you something.
Buzzing
Usually electrical — a failing contactor, capacitor or loose wiring at the outdoor unit. Sometimes a fan motor struggling to start.
Grinding or screeching
Motor bearings in the condenser fan or blower. Shut it down and call — a seized motor can take the capacitor with it.
Clicking
Constant clicking at the outdoor unit points to a relay or capacitor; a single click at startup is normal.
Hissing or bubbling
A refrigerant leak. Have it found and fixed rather than recharged.
Banging or rattling
Loose panels, a broken fan blade, or debris in the condenser. If it's coming from the compressor, stop the unit.
Gurgling from the air handler
A partially clogged condensate drain line — clear it before the float switch shuts the system off. Same-day
AC repair is available in every Florida city.
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