OEM Carrier High Pressure Switch 312926-252 & Low Pressure Switch 312926-258 for Model PH15NB03600GBAAA

This listing covers both factory-authorized OEM pressure switches for the Carrier PH15NB03600GBAAA heat pump system: the 312926-252 High Pressure Switch (670-470 PSI) and the 312926-258 Low Pressure Switch (55-23 PSI). Together, these switches form the refrigerant circuit's primary safety net — the high pressure switch cuts the compressor when refrigerant pressure climbs dangerously high (blocked condenser coil, failed fan motor, overcharge), while the low pressure switch protects against low-side faults such as refrigerant loss, a frozen evaporator coil, or a failed metering device. When either switch trips and will not reset, or trips repeatedly causing lockout faults, replacement is the correct fix.

• Part Numbers & Specs: 312926-252 High Pressure Switch — 670 PSI cut-out / 470 PSI cut-in | 312926-258 Low Pressure Switch — 55 PSI cut-out / 23 PSI cut-in | Both are Carrier Factory Authorized Parts (FAP), OEM-matched to the PH15NB03600GBAAA refrigerant circuit
• OEM vs Generic: Carrier FAP switches are calibrated to exact PSI set-points at the factory. Generic aftermarket switches frequently carry wider tolerances that allow the compressor to operate outside safe pressure windows, risking compressor failure and voiding equipment warranties.
• Install Difficulty: 3/5 — Refrigerant-side work requires EPA 608 certification. A licensed HVAC technician should recover refrigerant, replace the switch(es), pressure-test, and recharge the system. Tools needed: manifold gauge set, refrigerant recovery machine, torque wrench, multimeter. Always verify the switch has tripped (open circuit) before condemning it — check for underlying cause first.
• Warranty: 1-year OEM factory warranty on both parts. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Both 312926-252 and 312926-258 are direct OEM replacements for the Carrier PH15NB03600GBAAA single-stage R-410A heat pump. Verify your model and serial number against your unit's data plate before ordering. Not sure which switch failed? Our team can assist with fitment and part selection before you buy — in stock and ready to ship today.