My carrier ac roof top ducted unit started spitting out small amounts of water now and then, I changed filter. Now with ac in off position I am hearing a humming noise coming from the unit, what can this be. it hums and stops then hums again repeated cycle, will this damage anything?

SOURCE: compressor makes a humming noise

This web site is useless

SOURCE: RV Rooftop AC Unit

Sounds to me like your fan is hitting something
Remove the cover and turn the fan by hand ( with the power off ! ) See what it is hitting

SOURCE: AC compressor hums for a few secs then cycles off for few secs

Inspect all electrical wires and connections and correct any areas that appear damaged or overheated or loose (connections). There is a capacitor which is a round or oval component in series with the contactor and the compressor. Thoroughly mark all connections and remove the component. Take it to you local RV air conditioning repair shop and have them test it. If it is faulty, they will provide you with a replacement part. If it is not faulty and all wiring is okay, your compressor is locked up and will need to be serviced by a professional air conditioning technician.
Try the wires and the capacitor first.
I hope you find this information to be very helpful to you as a good, solid jumping off point moving forward.
:-)

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