Resideo T87N1000 Non-Programmable Thermostat 40-90°F

The Resideo T87N1000 is a round, non-programmable low-voltage thermostat for residential 1 heat/1 cool applications, covering conventional gas/oil/electric systems and heat pumps without auxiliary heat. It operates on 20-30V AC, 50/60 Hz, with a contact rating of 0.02A to 1.0A, and uses 18-22 AWG wire with screw terminals. The setpoint range is 40°F to 90°F with an operating range up to 110°F. It features an analog dial display, manual heat/off/cool changeover, and fan auto/on selection. Housed in Premier White, it measures 3.69" diameter x 1.75" deep and weighs 0.75 lbs, with battery or hardwired power options. This unit serves split systems, heat pumps, furnaces, and air handlers as an OEM replacement, suited for DIY-friendly installs. Recommended accessories include thermostat wire, wire connectors, and mounting hardware. Common failure symptoms addressed by replacement include an unresponsive thermostat, temperature not holding, failure to switch between heat and cool, fan not running on auto, or a dial that is stuck or hard to turn. Backed by a 5-year warranty.