[Peazoup]

I have a mini split in my lanai that needs service. It was installed about 6 years ago and cools and heats perfectly except now it has started to hum intermittently, sometimes hours after the unit has been turned off. I've had one what I believe to be an outrageous estimate to replace the pump. Has anyone had experience with companies servicing these units and can give me a recommendation so I can get another estimate? Thanks for any advice.