Customer said thermostat was reading room temperature higher than actual temperature and making it colder than their actual setpoint. Verified contactor in unit was not sticking. Ran thermostat up and down several times and observed system turn on and off normally. This thermostat needs batteries to operate and batteries in thermostat have been in at least a year and a half per customer. Weak batteries can cause operating issues with thermostat. Replaced with new batteries supplied by customer. System is running normally at this time. No answer to phone at this time. BILL CUSTOMER