Honeywell Mercury Free Thermostat (Model CT87K1004)

The Honeywell Mercury Free Thermostat is a classic, non-programmable heat-only control designed for reliable home heating performance. Its familiar round profile and simple turn-dial operation deliver precise comfort with ±1°F accuracy—without the environmental concerns of mercury. A matte white finish and decorative cover ring hide wall blemishes, providing a clean, finished look.

Ideal for single-stage heating systems—including hot water, gas, or steam—the CT87K1004 mounts easily on any wall and hard-wires to your 24 V system for steady, maintenance-free power. The intuitive analog dial makes temperature adjustments quick and effortless.

Key Features

• Mercury-free construction for safer, eco-friendly operation
• Precise ±1°F temperature control
• Classic round design with matte white finish
• Decorative cover ring conceals wall marks and wiring
• Manual dial interface for quick, intuitive adjustments
• Hardwired 24 V power source (no batteries required)
• Compatible with most single-stage heating systems
• Easy wall-mount installation

Note: Not compatible with heat pump systems.