OEM Carrier High & Low Pressure Switch for Model CH13NA03600GAABA

These OEM pressure switches — 312926-252 (High Pressure Switch) and 312926-258 (Low Pressure Switch) — are the factory-specified replacements for the Carrier CH13NA03600GAABA condensing unit. Pressure switches prove that the inducer motor has established adequate draft before allowing the ignition sequence to proceed. When either switch fails or sticks open, the control board will lockout the system before the burners ever fire, leaving you with no heat and a blinking fault code. Common symptoms include repeated ignition lockouts, a spinning inducer with no further start sequence, or a fault code pointing to a pressure switch circuit fault.

• Specs: 312926-252 — High Pressure Switch | 312926-258 — Low Pressure Switch | Factory W.C. (water column) rating matched to OEM specifications for the CH13NA03600GAABA | SPST normally-open contacts | 1/4" Spade terminals
• OEM vs Generic: OEM switches are calibrated to exact factory W.C. trip points. Aftermarket substitutes often carry ±15% tolerance on actuation pressure, which can cause nuisance lockouts or, worse, allow the unit to fire under unsafe draft conditions — always use OEM on pressure switches.
• Install difficulty: 2/5 — Shut off power at the disconnect before beginning. Tools needed: 1/4" nut driver, flathead screwdriver, needle-nose pliers, and a manometer if verifying trip pressure. Photograph or label the rubber hose routing before disconnecting. Swap one switch at a time to confirm the faulty unit.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse — order by 3 PM local time for same-day dispatch.

Compatibility: Both switches are engineered specifically for the Carrier CH13NA03600GAABA condensing unit. Verify your existing switch part number (printed on the switch body label) against 312926-252 or 312926-258 before ordering to ensure correct W.C. rating. If your fault code points to the pressure switch circuit but both switches test closed, also inspect the rubber sensing hoses for cracks or blockages. Questions about fitment? Our HVAC parts specialists verify compatibility before every order ships.