Carrier HH19ZH175 Limit Switch 322838-753 We recommend retaining original hardware

We recommend retaining original hardware or sourcing high-grade corrosion-resistant fasteners for the install

and HCG-150 models

The flow arrow must point toward the expansion device

For commercial reliability

While installation is straightforward

Carrier HH19ZH175 Limit Switch 322838-753 We recommend retaining original hardwareAs a field tech, you know that a failed safety circuit is the fastest way to a no heat call. The Carrier HH19ZH175 is a critical furnace high limit switch designed to protect the heat exchanger from thermal stress. This 175F limit switch features a normally closed (CO) configuration, meaning it stays shut during standard operation and opens the circuit at its 175 degree setpoint to kill the gas valve or heating elements. This specific HH19ZH175