OEM Carrier High Pressure Switch 448 PSI Open / 327 PSI Close for Model TFACCY50DK480403

This OEM high pressure switch is the factory-specified replacement for the Carrier TFACCY50DK480403 packaged rooftop unit. The high pressure switch continuously monitors refrigerant circuit pressure on the high side of the system. When refrigerant pressure exceeds the 448 PSI trip point — caused by a dirty condenser coil, blocked airflow, refrigerant overcharge, or a failing condenser fan motor — the switch opens the safety circuit and shuts down the compressor to prevent catastrophic damage. When pressure drops to the 327 PSI reset point, the switch closes and allows the system to restart. A failed or weak pressure switch can cause nuisance lockouts, compressor short-cycling, or — if stuck closed — allow dangerous overpressure conditions to go undetected.

• Specs: 448 PSI open (trip) | 327 PSI close (reset) | OEM Part Numbers: HK02ZA442 (High Pressure Switch) & HK02ZB044 (Pressure Switch) | Replaces HK02ZA439 | Rated 6(6)A | Factory Authorized Part
• OEM vs Generic: OEM switches are manufactured to exact Carrier factory trip-point tolerances. Aftermarket pressure switches frequently carry wider pressure tolerances, risking either premature nuisance trips or delayed shutdowns that can damage the compressor.
• Install difficulty: 3/5 — Requires EPA 608 certification to recover refrigerant if accessing a pressurized circuit. Tools needed: manifold gauge set, refrigerant recovery unit, adjustable wrench, electrical multimeter. Always recover refrigerant before disconnecting pressure switch lines and lock out/tag out (LOTO) the unit before beginning any electrical work.
• Warranty: 1-year OEM factory warranty. Orders placed by 3 PM local time ship same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for Carrier TFACCY50DK480403 commercial packaged rooftop units. Cross-references OEM part numbers HK02ZA442 and HK02ZB044. Always verify your unit's data plate and existing switch pressure ratings before ordering. Need fitment confirmation? Our HVAC parts specialists are standing by to verify compatibility before you check out.