Cuts fuel costs and provides utmost comfort performance from conventional hot water heating systems; especially ideal for zoned systems Features: • Fully adjustable reset ratio covers all climate conditions and eliminates stocking controls with different reset ratios • Well-insertion bulb monitors boiler water temperature, outdoor bulb monitors outdoor temperature. Control\modulates water temperature based on reset ratio selected • Hydraulic action elements unaffected by vibration or moisture • Easy to wire screw terminals • Mounting clamp for outdoor bulb included • F089-0148 well included with control Specifications: Dimensions: 9" H 9 x 3 1/2" W x 4" D Capillary Length: 15 feet to insi