Customer called for heater not kicking off after being set to customers preferred temperature. Customer could tell it was way hotter than what the thermostat was set to. Upon inspection I found the Honeywell T1 thermostat glitching causing the system to not stop heating surpassing set temperature. Replaced the batteries first to see if that was the issue. The batteries didn’t make a difference. Replaced the thermostat under new install warranty with a 1H/1C Honeywell T4 thermostat since I didn’t have a T1. Customer just wanted the thermostat to work as it should and be as simple as possible. System is now operating properly at this time. No charge due to new install.