The Honeywell Round Mechanical Thermostat Heat Only CT87K is a white wall-mounted thermostat designed for central furnaces. It operates on low voltage and features a 3-wire configuration, suitable for controlling the heat-off system switching. The thermostat has a rotary knob control style with analog/mechanical operation, allowing for easy temperature adjustments. With a durable construction of aluminum, plastic, and steel, this Honeywell model includes features like a rotation direction indicator and an adjustable thermostat, making it a reliable and user-friendly option for maintaining a comfortable indoor temperature. aamm
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