The White-Rodgers 661959 is a 5-1-1 day programmable thermostat designed for single-stage residential and light commercial HVAC systems. It supports 1st-stage heat (gas, oil, electric, or heat pump without auxiliary heat) and 1st-stage cooling via compressor, with compatibility for millivolt systems and includes B/O terminals for added versatility.
Featuring an LCD display with backlight, selectable Celsius or Fahrenheit readout, electronic accuracy, and Energy Management Recovery, this thermostat helps optimize comfort and efficiency. It operates on hardwired power or 2 AA Energizer alkaline batteries (included), making installation flexible and straightforward.