OEM Carrier High & Low Pressure Switch Kit — 312926-252 & 312926-258 for Model PH14NB03700GAAAA

These are the factory-specified OEM replacement pressure switches for the Carrier PH14NB03700GAAAA heat pump. The high pressure switch (312926-252, 670/470 PSI) monitors refrigerant discharge pressure and cuts the compressor if it exceeds safe limits — protecting against catastrophic compressor failure. The low pressure switch (312926-258, 55/23 PSI) monitors suction-side pressure and shuts down the compressor under low-charge or refrigerant-starved conditions. When either switch fails, you may experience nuisance lockouts, a compressor that won't start, or a system that trips on a pressure fault code and requires manual reset.

• Specs — High Pressure Switch (312926-252): 670 PSI cut-out / 470 PSI cut-in | Factory Authorized Part | OEM cross-reference: LP18-094 | Manufacturer: Sensata
• Specs — Low Pressure Switch (312926-258): 55 PSI cut-out / 23 PSI cut-in | Factory Authorized Part | OEM cross-reference: PSL 312926-258 / PS80-02-F1270 | Manufacturer: Sensata
• OEM vs Generic: Genuine Carrier OEM switches are calibrated to exact factory cut-in/cut-out tolerances. Aftermarket substitutes frequently drift ±10–15 PSI, causing nuisance trips or — worse — failing to protect the compressor under true fault conditions.
• Install Difficulty: 3/5 — Requires recovering refrigerant before accessing refrigerant-side ports. Tools needed: manifold gauge set, wire strippers, 1/4" flare fittings, multimeter for continuity check. EPA 608 certification required for refrigerant handling. Always confirm system pressure before re-energizing.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse.

Compatibility: Engineered as direct OEM replacements for Carrier model PH14NB03700GAAAA. Verify PSI ratings on your unit's data plate or wiring diagram before ordering. Unsure which switch you need — high, low, or both? Our HVAC parts specialists confirm fitment before you buy. Order now and we'll ship today.