Weil McLain 635-100-010 Thermostat

The Weil-McLain 635-100-010 is a heavy-duty commercial thermostat designed for high-demand hydronic heating and indirect water heater systems. Engineered to operate within a precise 90°F to 190°F temperature range, this mechanical stat is the OEM replacement for controlling Plus 80, Plus 100, Plus 120, and Gold Plus 100/110/119 series commercial water heaters. As a veteran-grade HVAC control, it features a rugged bulb-and-capillary sensing element that ensures accurate thermal response and long-term calibration stability in mechanical rooms.

This 90/190F commercial thermostat kit includes the necessary adjustment knob and mounting hardware for immediate field installation. It is specifically calibrated for Weil-McLain indirect-fired water heaters, providing the reliable high-limit and operating control required to maintain setpoint integrity. For technicians performing boiler maintenance or system retrofits, this component ensures seamless integration with existing 24V control circuits, maintaining the efficiency and safety parameters of the original equipment design.

• Broad Operating Range: Supports settings from 90°F to 190°F, ideal for high-temperature commercial sanitation and domestic hot water needs.
• Direct OEM Compatibility: Engineered specifically for Weil-McLain Plus and Gold Plus series indirect tanks.
• Mechanical Reliability: Simple, robust design eliminates the failure points of electronic interfaces in high-humidity environments.
• Field Serviceable: Includes the replacement knob and kit components for a complete professional installation.

Is this thermostat compatible with residential Gold Plus tanks?
While designed for commercial models like the Plus 100 and Gold Plus 119, it functions as a direct replacement thermostat for series requiring the 90-190°F range. Check your specific manual for the 635-100-010 part number.

Does this kit include the immersion well?
This is the thermostat kit with knob; standard installations typically utilize the existing dry well on the Weil-McLain tank. Always verify bulb-to-well contact for accurate sensing.

Can this be used for space heating control?
This unit is calibrated for water heater temperature control and high-limit applications. It is not intended for use as a standard wall-mounted room thermostat.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.