Hi, I have moved into a house where the unit is already installed but there is no users manual here. I requested a users manual but the manual provided is titled FOR SERVICE PERSONNEL ONLY, and is far too technical for me to comprehend. Is there a simple explanation available that just tells me how to operate the unit. I am not interested in replacing coolant or rewiring it or anything other than just using it. The Model # on the Heat Pump is RAC-50YHA2.