Hayward CZ/HM/HM2 Thermostat w/o Knob (CHXTST1930) oreq A hi-limit sensor is useful

A hi-limit sensor is useful because it helps the control system respond to unsafe heat conditions before they become a larger problem

When the original basket becomes damaged or brittle

Black finish helps preserve original equipment appearance

The Raypak Unitherm Governor spring is designed for compatible 105A

A properly selected bag helps support cleaner debris handling and contributes to more dependable setup in specialized cleaning situations

Hayward CZ/HM/HM2 Thermostat w/o Knob (CHXTST1930) oreq A hi-limit sensor is usefulThis thermostat is used on compatible Hayward CZ, HM, and HM2 heater systems where temperature regulation hardware needs replacement but the control knob is not required. It is a practical service part for restoring proper heater response when the existing thermostat is worn, inconsistent, or no longer controlling the system correctly. For pool and spa heaters, small control components can make a noticeable difference in comfort and reliability.