Weil-McLain®, 633-900-102, Thermostat with Cover Plate Kit

Weil-McLain 633-900-102 Thermostat and Cover Plate Kit for Indirect Water Heaters

The Weil-McLain 633-900-102 Thermostat Kit is designed for use with select Weil-McLain indirect water heater models, including Gold and Ultra Plus units ranging from 30 to 80 gallons. This kit includes the necessary components for accurate temperature regulation and secure assembly of the control housing.

Engineered for system compatibility and field serviceability, the kit includes a thermostat, control knob, snap set, and cover plate with mounting hardware. It is used to maintain water temperature settings within the standard operating range for domestic hot water applications.

Kit Components

• Thermostat: Adjustable temperature control for indirect-fired water heaters
• Knob and Snap Set: For temperature setting and mechanical engagement
• Cover Plate: Protects thermostat and provides labeled access
• Mounting Hardware: Includes fasteners for secure panel attachment

Application and Compatibility

• Compatible Models: Weil-McLain Gold Plus and Ultra Plus 30, 40, 60, and 80-gallon indirect water heaters
• System Type: Closed-loop hydronic systems with indirect domestic hot water generation
• Temperature Range: Designed to regulate within manufacturer-specified domestic hot water parameters

Installation Notes

Installation of the 633-900-102 kit should be performed by qualified personnel familiar with indirect water heater operation and safety protocols. Proper mounting and electrical connection of the thermostat ensure safe operation and system efficiency. Verify voltage compatibility and wiring configuration prior to installation. Follow all local mechanical and electrical codes.

Contractor Guidance

This kit provides a direct-fit replacement for original thermostat assemblies supplied with qualifying Weil-McLain indirect water heaters. It supports field maintenance, repairs, and retrofit installations where the control interface or thermostat requires replacement due to wear, damage, or operational drift. Use in accordance with manufacturer documentation to restore OEM functionality.