re: Reminder, now is a good time to pick up a spare capacitor for your HVAC

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Any ideas on what to check if the capacitor didn't get it running? Blade spins freely, and the air handler inside is running fine.

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Are you getting sound as though the unit is try to start? Humming of the compressor? Have you tried to spin the fan blade through the grill with a stick or screw driver to see if the fan will start when the unit is turned on and calling for cooling?

Let’s assume the new capacitor is good and not bad from the factory - even the HVAC techs on YouTube videos I watch check the capacitance (uF) of new capacitors with a multimeter before they install them which tells me that some new ones must be bad from the factory.

Pull the outside dissconnect, to remove 240 V power to the condensing unit, then check all your electrical connections on the capacitor, to make sure they are tight, also check for loose electrical wire connections at the contactor.

It’s possible it may be a bad contactor or bad fan motor. I had to replace a fan motor on mine last year - the motor windings were good but the bushing/bearings were bad. With a strong flip of the fan blade with a finger, the fan blade on a motor with good bushings may turn a few complete revolutions, but with bad bushings the blade will turn a 1/4 or 1/2 a revolution. You can easily check that your yourself without removing the fan motor - just try spinning it through the grill. You said the fan it’s spinning freely so the motor windings might be bad

Contactors can become pitted with age, insects (ants, etc,) get inside the contactor and cause the contacts not to closely. Check the two very small 24 V wires that attach to the contactor to make sure one of them is not broken - they send the signal from the thermostat to close the contractor when the unit calls for cooling. And it could be an issue with the thermostat even though your air handler runs.

Aside from refrigerant leaks, the 3 most common service calls that HVAC techs need to fix/repair in order are 1. bad capacitor, 2. bad contactor, and 3. bad fan motor. I learned that from watching a YouTube HVAC training video.

Beyond these simple things to try, looks as though you’ll need call a HVAC tech.