Computer program products, devices, systems, and operations for early detection of poor performance and failure of a climate control system. The invention provides operations for computing an actual run time percentage (ART) from operational data of the climate control system, and operations for computing an estimated run time percentage (ERT) of the climate control system from temperature data of an uncontrolled climate. The invention also provides operations for issuing one or more alerts if the ART deviates from the ERT or a range thereof.