Check thermostat check blower motor check filter customer supply. Check condensate drain and pump working. Found condensate drain was clod blow it out. Supply air 47* return air 66*. Check disconnect check capacitor. Found capacitor was reading 37+3+440 and recommended is 40+3+440. Customer said he will work it until it go. Cycle unit on to check compressor and fan motor working. Wash and clean condenser coil. Outdoor temperature 75*. At times of dispatch unit is working. NB there no model or serial no present on unit.