Performed diagnostic work checking refrigerant charge, wiring connections, air filter and found that the thermostat that was replaced during the last visit is a Honeywell T4, 1H/1C thermostat. A Honeywell T4 2H/1C thermostat is needed. We will need to send a technician back with the correct style T4 thermostat. N/C, WARRANTY. Note-Service manager will schedule the return visit with the homeowner after today’s visit.