Upon arrival, only indoor fan motor would come on from thermostat.testing revealed the thermostat was defective. Bypassed thermostat and tested system. Found compressor to be consuming a lot of power and is in danger of failing. Capacitor is also reading weak. Outdoor fan motor is leaking oil and is slowing down. System is original to the house and runs on an obsolete refrigerant and needs to be serviced. Attempted to call homeowner to go over findings. Client was not available by phone. Just installed the thermostat and informed tenant on how to operate it. Unit is operational upon departure.