I installed a mini-split from Mr. Cool in the summer of 2020. Mine was the 3rd-generation, 12,000 BTU, unit that runs on 115v. (My shop's sub-panel was full and I couldn't run a 220v circuit for the mini-split.) My shop is small (about a 1-car garage size), but it's located in Mesa, Arizona. So, 12,000 BTUs is a bare minimum. When it's 115 degrees outside, the mini-split will keep the temperature below 85 degrees inside the shop. Frankly, I was thrilled.
This past April, I noticed that the mini-split wasn't cooling. (Yes, we need A/C in April!) It was about time for our various A/C units to receive their annual service, so I arranged for that. My tech told me that the Mr. Cool's mini-split's compressor had died and needed to be replaced. This was disappointing.
However, the unit was still under warranty so I emailed Mr. Cool's customer service department. The process went very smoothly. Under the tutelage of one of Mr. Cool's warranty tech's, I performed some basic tests with my multi-meter. The tests showed that the compressor was dead and needed to be replaced. Mr. Cool sent me a new condenser (the entire outside unit), all I had to pay was about $115 shipping. The new condenser is a slightly different, upgraded, version of my old one. The new condenser came with a new line-set, so I could have installed it myself. However, I opted to have my A/C tech install it at a cost of $120. It was over 95 degrees today and the shop never got over 74 degrees. I'm a happy camper again.
Bottom line: Mr. Cool honored their warranty. The warranty process went very smoothly. Am I happy that the old compressor failed after 3 years? No, of course not. However, I'm very pleased with how Mr. Cool resolved the situation.