If the HH18HA452 is sensing temperatures above 250°F

Safety Calibration: 160°F open temperature prevents catastrophic heat exchanger failure

along with various gas valve burner assemblies

System Protection: Actively prevents furnace overheating by monitoring air temperature in the supply plenum and interrupting the gas valve circuit if limits are exceeded

Key Benefits Infinite Adjustability: Allows for exact stroke tuning to match specific damper travel requirements without fixed-hole limitations

Lochinvar & A.O. Smith 100208241 Reset Switch If the HH18HA452 is sensingThe Lochinvar & A. O. Smith 100208241 Manual Reset Switch is a critical OEM safety component designed for high efficiency hydronic boilers and commercial water heaters. This high limit manual reset switch, which is the direct replacement for part SWT2004, monitors internal temperatures and provides a hardware level safety lockout to prevent equipment damage in the event of a thermal overrun. As a genuine Lochinvar replacement part, it ensures precise