CT87K1004/U1 Round Heat-Only Thermostat, Mercury-Free, 24V

The Honeywell CT87K1004/U1 is a classic round, non-programmable thermostat designed for heat-only systems. This mercury-free thermostat provides straightforward, reliable temperature control using a simple round dial that is intuitive and easy to adjust daily. It is ideal for homes heated by forced air (gas, oil, or electric), hot water, or steam systems.

This thermostat is not compatible with heat pump systems. The decorative cover ring hides old wall marks and blemishes left by previous thermostats, giving your wall a clean, finished appearance after installation. Backed by a 1-year limited warranty, the CT87K delivers dependable performance for straightforward heating needs.

Features and Benefits

• Mercury-Free: This thermostat uses a mercury-free design.
• Round Dial Design: Simple and precise round dial that has been celebrated for its ease of use, making daily temperature adjustments straightforward.
• Decorative Cover Ring: Conceals wall marks and imperfections from previous thermostat installations for a clean, professional appearance.
• Heat-Only Compatibility: Works with forced air furnaces (gas, oil, or electric), hot water boilers, and steam heating systems—the most common residential heating types.
• User-Friendly Operation: No programming or complex menus; adjust temperature manually with the easy-to-read round dial.
• 1-Year Limited Warranty: Manufacturer-backed protection for added peace of mind.

Specifications

• Brand: Honeywell
• Model: CT87K1004/U1
• Type: Round heat-only thermostat
• Voltage: 24V
• Mercury-Free: Yes
• Compatible Systems: Forced air furnaces (gas, oil, electric), hot water, steam; not compatible with heat pumps
• Features: Decorative cover ring, round dial, manual control