Ao Smith 100108641 Lower Thermostat with Eco Cover

Product Description

The AO SMITH 100108641 is a lower thermostat with ECO (Energy Cut-Off) cover designed for residential water heater applications. This control component regulates the lower heating element on electric water heaters, maintaining the set water temperature and cutting power if an unsafe temperature condition is detected. The integrated ECO cover provides protection for the safety cutout switch, a critical safety and code-compliance feature on electric storage water heaters. Installation is typically performed by licensed plumbers or water heater service technicians.

This thermostat is intended for heating applications and corresponds to the WH9HC-6 model designation in the AO SMITH product line. It is used in electric storage-type water heaters where a lower thermostat controls the bottom heating element during standard recovery cycles. The ECO cover is included, making this a complete control assembly ready for direct installation without sourcing separate components.

Key Features

• Lower thermostat position controls the bottom heating element on electric water heaters
• Integrated ECO (Energy Cut-Off) cover included for safety cutout protection
• Designed for the heating application control function in electric storage water heaters
• WH9HC-6 model designation for direct OEM-style replacement reference

Compatibility

Designed as an OEM-style replacement lower thermostat for AO SMITH electric storage water heaters using the WH9HC-6 thermostat specification. Verify thermostat model designation and element voltage against the existing unit before installation.

Installation Notes

Installation should be performed by a licensed plumber or qualified water heater technician. Always shut off the electrical supply at the breaker and close the cold water supply valve before servicing the thermostat or any internal water heater components. Drain or relieve pressure as needed before accessing the lower element panel. Refer to the water heater manufacturer wiring diagram located inside the access panel and follow all applicable local electrical codes during replacement.

Technical Specifications

• Application: Heating
• Model Reference: WH9HC-6
• Product Type: Control

Standard Information

• Brand: AO SMITH
• Manufacturer Part Number: 100108641