OEM Carrier High Pressure Switch 448#OPN / 327#CLS for Model PY1RPA048074AAWB

This is the genuine OEM Carrier high pressure switch (part number HK02ZA442) factory-specified for the Carrier PY1RPA048074AAWB packaged unit. The high pressure switch is a critical refrigerant-circuit safety device: it continuously monitors refrigerant discharge pressure and opens the circuit to shut down the compressor if pressure exceeds the trip point. When it fails or trips, you'll typically see nuisance high-pressure lockouts, compressor short-cycling, or a system that won't run at all even when refrigerant charge and airflow are verified normal. This listing also includes the companion low pressure switch HK02ZB044 (7#OPN / 22#CLS, 50" leads), which protects the low side of the refrigerant circuit — together these two switches provide complete factory refrigerant-circuit pressure protection for the PY1RPA048074AAWB.

• Specs (HK02ZA442 — High Pressure Switch): Opening pressure: 448 PSI | Closing pressure: 327 PSI | OEM part replaces HK02ZA439 | Made in Mexico | Factory-matched trip tolerances for reliable compressor protection
• Specs (HK02ZB044 — Low Pressure Switch): Opening pressure: 7 PSI | Closing pressure: 22 PSI | 50" lead wire | 24V control circuit | OEM Carrier/Bryant/Payne genuine part
• OEM vs Generic: OEM pressure switches are calibrated to exact factory trip points. Aftermarket units frequently deviate from rated open/close pressures, allowing unsafe operating conditions that shorten compressor life or create refrigerant circuit damage.
• Install difficulty: 3/5 — Refrigerant circuit work requires EPA 608 certification. Discharge system pressure before disconnecting. Tools needed: manifold gauge set, 1/4" nut driver, needle-nose pliers, multimeter. Photograph wiring before removal. Always verify system charge and airflow before condemning pressure switches.
• Warranty: 1-year OEM factory warranty on both switches. Orders placed by 3PM ship same business day from our warehouse.

Compatibility: These switches are the factory-specified OEM replacements for the Carrier PY1RPA048074AAWB packaged unit. Verify part numbers against your unit's wiring diagram and data plate before ordering. Not sure about fitment? Our HVAC parts specialists will confirm compatibility before you buy — contact us today and get your system back online fast.