OEM Carrier Flame Sensor LH33WZ518 for Model PG9MXA048080AASA

This is the genuine OEM Carrier flame sensor (part #LH33WZ518), the factory-specified replacement for the Carrier PG9MXA048080AASA gas furnace. The flame sensor is a safety-critical component — a small metallic rod that produces a microamp DC signal when it detects a burner flame, confirming ignition to the integrated furnace control board. When the sensor fails or becomes coated with oxidation, the control board cannot verify flame presence and will shut off the gas valve within 5–8 seconds of ignition as a safety lockout. The result: your furnace lights briefly, then goes out — repeating the cycle until it locks out entirely.

• Part Number: LH33WZ518 | OEM Carrier | Factory-direct replacement for PG9MXA series gas furnaces
• OEM vs Generic: OEM flame sensors are precision-matched to the exact microamp threshold required by the Carrier control board. Aftermarket rods often use inferior alloys that oxidize faster, leading to repeated nuisance lockouts within months of installation.
• Install Difficulty: 2/5 — Turn off power and gas before servicing. Tools needed: 1/4" hex driver or nut driver, needle-nose pliers. Locate the sensor on the burner assembly, disconnect the single wire lead, remove the mounting screw, and swap the rod. Tip: lightly sand the rod with fine steel wool if reusing; always install new for a permanent fix.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Fits Carrier model PG9MXA048080AASA and other PG9MXA0 series gas furnaces. Also compatible with select Bryant, Carrier, and Payne units across the 58MEC, 58MTA, 58MTB, 352AAV, and 352MAV series — verify your unit's data plate and existing part number before ordering. Our fitment team is available to confirm compatibility before you purchase.