OEM Carrier High & Low Pressure Switch Kit — HK02ZA395 & HK02ZB044 for Model PH1PPB030000AAAA

This OEM pressure switch kit includes both the HK02ZA395 High Pressure Switch and the HK02ZB044 Low Pressure Switch, the factory-specified safety controls for the Carrier PH1PPB030000AAAA packaged heat pump unit. Together, these switches continuously monitor refrigerant circuit pressure — the high-side switch opens at 395 PSI to protect the compressor from dangerously elevated discharge pressure, while the low-side switch opens at 7 PSI to guard against refrigerant loss and loss-of-charge conditions. When either switch fails or trips and won't reset, the system will go into lockout mode, delivering no heating or cooling. Common symptoms include a system that starts briefly then shuts down, a compressor that won't engage, or a fault code indicating a pressure trip on your thermostat or control board.

• Specs — HK02ZA395: High Pressure Safety Switch | Open: 395 PSI | Close: 295 PSI | 240 VAC | 1/8" NPT Thread | Sensata PS80-03-0018 | Replaces: 312926-217, 71267D1, HK02ZA380, HK02ZA396, HK02ZA400, HK02ZA401, HK02ZA435
• Specs — HK02ZB044: Low Pressure Cutout Switch | Open: 7 PSI | Close: 22 PSI | 24V | 50" Lead | OEM Carrier/Bryant/Payne
• OEM vs Generic: Both switches are genuine Carrier OEM parts manufactured to factory-exact setpoints. Aftermarket pressure switches frequently carry wider trip tolerances, risking nuisance trips or — more critically — failure to protect the compressor under true fault conditions, leading to costly compressor replacement.
• Install Difficulty: 3/5 — Refrigerant circuit work requires EPA 608 certification. Always recover refrigerant before accessing high-side ports. Tools needed: manifold gauge set, 1/4" and 3/8" flare wrenches, multimeter for continuity check, and leak detection solution. Photograph all wiring before disconnecting. Low-side switch swap on the control circuit side is straightforward for experienced technicians.
• Warranty: 1-year OEM factory warranty on both switches. Ships same business day from our warehouse.

Compatibility: Factory-matched for the Carrier PH1PPB030000AAAA packaged heat pump unit. The HK02ZA395 is also a known cross-reference for numerous Carrier, Bryant, and Payne split and packaged systems — always verify PSI setpoints against your unit's data plate or wiring diagram before installing. Have questions about fitment? Our HVAC parts specialists verify compatibility before you order — contact us today and ship the same business day.