Carrier HH18HB031 Freeze Stat

Installing a Carrier HH18HB031 Freeze Stat is a critical preventative measure for any light commercial or residential split system prone to coil icing. This OEM frozen coil protection switch is a Single-Pole Single-Throw (SPST) device designed to interrupt the compressor circuit when temperatures drop below safe thresholds. Specifically calibrated for high-reliability freeze protection, the contacts open at 30°F and automatically reset/close at 45°F, ensuring the system does not short-cycle while allowing the evaporator to shed ice before restarting.

For service technicians, the HH18HB031 provides a universal fit for many Carrier, Bryant, and Payne air handlers and package units. Utilizing a temperature safety switch like this prevents catastrophic liquid slugging and potential compressor failure in scenarios involving restricted airflow or low ambient operation. Its 30/45 degree differential is the industry standard for HVAC freeze stats, providing enough headroom to avoid nuisance trips while delivering immediate protection during real-world icing events.

• Direct OEM Replacement: Matches factory specifications for Carrier, Bryant, and Payne systems, ensuring electrical and mounting compatibility.
• Fixed Calibration: Non-adjustable 30°F open and 45°F close settings eliminate field error and ensure consistent protection.
• Rugged SPST Design: Built-in single-pole single-throw logic allows for simple series-wiring into the 24V cooling call circuit.
• Coil Safeguard: Actively prevents ice buildup that causes restricted airflow and mechanical strain on the compressor.

• Where should this freeze stat be mounted? It is typically clipped onto the return bends of the evaporator coil or fixed to the suction line near the outlet to accurately monitor the coldest part of the circuit.
• Can this be used for refrigeration applications? Yes, while common in comfort cooling, it is also found in commercial refrigeration units where low-temperature cut-off is required to prevent component damage.
• Does this require a manual reset? No, this auto-reset thermostat will automatically re-engage the circuit once the sensed temperature rises back to 45°F.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.