We live in a low floor unit condo and have a 4 year old Bosch water source heat pump AC in a separate closet in our hallway. For some reason the AC stopped working and it got to 86 degrees in our unit. We called an AC company who after inspecting said we need to change 2 parts TXV valve and heat exchanger which is expensive and that they don’t do that job. Called a second company who said we need to change the expansion valve since it got ruined by dirt and pebbles that came through main building pipe likely when roof work was being done. That got changed but still no cool air and remained 86 degrees. Tech came back on 4 subsequent days to try to check problem but said disappointedly that he does not know what the problem is as all pressures and readings on the unit are ok and suggests to replace the AC. I called 3rd company who also said all readings including Freon are ok and maybe there are uninsulated openings in the closet that might be contributing to the problem but still he did not fix problem. As a last resort before buying a new unit which made no sense since it’s only 4 years old , I called Cool Air USA. They sent Leo who found the problem within 10 minutes. The drain pan was dirty which did not allow the water to drain and eventually the water in the pan rose and sensor shut off compressor which is a safety mechanism. After he cleaned it and finished tune up the AC starting cooling and compressor has been working. That was a great relief for my family as this was a 2 week problem and we ended up staying at air bnb and spending alot of money . The only thing I can’t figure out is how to stop our AC unit getting flooded every time it rains heavily. There seems to be a back up from main building pipe and since we live on bottom floor we get flooding of the AC. I’m not sure if there exists a mechanism to stop that. Anyways , thank you Leo and thank you Cool Air USA