Coates Heater Electric Pool/Spa Heater Replacement Parts 22003820 Hi-Temperature Limit, bulb type (Hi-Limit Reset) CPH PHS CE ST ILS IL

The Coates Heater Replacement Part 22003820 (Hi-Temperature Limit, bulb type – Hi-Limit Reset) is a critical safety component designed for use in Coates electric pool and spa heaters.

This bulb-type high-limit switch functions as a protective device that automatically shuts down the heater if water temperature exceeds safe operating limits, preventing overheating and potential damage to internal components. Featuring a manual reset mechanism, it ensures controlled reactivation once conditions are stabilized. Compatible with multiple Coates heater series—including CPH, PHS, CE, ST, ILS, and IL models—it integrates seamlessly into the system, supporting safe operation, equipment longevity, and reliable performance in both residential and commercial aquatic environments.