Programmable Thermostat

The Resideo TH1110DH1003 (Honeywell PRO 1000) is a horizontal non-programmable digital thermostat engineered for light commercial and residential HVAC applications requiring reliable temperature control without complex scheduling features. This thermostat is specifically designed for single-stage heating and cooling (1H/1C) systems, making it ideal for conventional air conditioning, heat pump installations without auxiliary heat, and millivolt-compatible systems at 750 mV. The unit features a backlit LCD digital display that clearly shows current room temperature, set point, and active heating or cooling mode indicators, ensuring easy readability in any lighting condition. Dual power options provide installation flexibility, supporting hardwired operation at standard HVAC voltages (20-30 VAC nominal, typically 24 VAC) while also offering battery backup capability with included batteries and low battery indicator for uninterrupted operation during power interruptions. Operator controls include a manual slide switch for Heat/Cool/Off mode selection and a separate fan switch with Auto and On positions, allowing technicians and end users to quickly adjust system operation without electronic programming. The thermostat delivers precise temperature control within plus or minus one degree Fahrenheit (plus or minus 0.5 degrees Celsius) for consistent comfort maintenance. This replacement unit is compatible with the original Resideo HONTH1110DH1003 specification and serves as a direct solution for system upgrades, maintenance, and repair applications. Its straightforward mechanical design ensures straightforward installation in standard wall-mounted applications typical of commercial office buildings, light industrial spaces, and residential properties.