OEM Carrier Flame Sensor LH33WZ for PG9MAA048100ABKA

The flame sensor verifies that the burners on your Carrier PG9MAA package unit have actually ignited. Once the burners light, the control board passes a small AC voltage through the sensor rod and reads back a tiny microamp DC current produced as the flame rectifies the signal through its ions. No current means no proven flame, so the board immediately shuts the gas valve to keep unburned gas out of the heat exchanger. As the rod oxidizes or builds a silica film, that current weakens and the furnace begins to short-cycle — burners light for a few seconds, drop out, retry, and finally lock out, leaving the house cold. This is a single-rod sensing electrode with a high-temperature ceramic insulator and the terminal matched to the 9MAA wiring harness. A clean, healthy sensor reads about 2–6 microamps DC; readings under roughly 1.0 µA cause the dropouts and lockouts you're chasing. The Kanthal sensing rod tolerates continuous direct flame contact without warping out of position. Why OEM: the rod length, bend, and mount position place the tip in the hottest, most ionized zone of the flame for the strongest, most stable signal. Generic sensors often differ slightly in geometry or use lower-grade insulators that crack and bleed current to ground — recreating the very intermittent lockouts you replaced the part to fix. Installation difficulty: 1/5. Tools: 1/4" nut driver and a fine abrasive pad. #1 safety warning: turn off the gas at the unit shutoff and kill power at the breaker before reaching into the burner compartment. Handle the new sensor by its bracket, not the rod. Ships same business day from our stocked warehouse on orders placed before 3 PM CST. Backed by a 1-year OEM warranty and 30-day hassle-free returns on uninstalled parts.

Compatibility

This part is compatible with Carrier model PG9MAA048100ABKA. Always verify the part number against your unit's data plate before ordering.

Why Choose OEM?

OEM parts are manufactured to the exact factory specifications for your unit. Generic aftermarket alternatives may fit physically but often use lower-rated components that reduce equipment life and void manufacturer warranties. When the cost difference between OEM and generic is $10-30, the OEM part is always the smarter investment on a system worth $5,000-$15,000.

Shipping & Returns

Same-day shipping on orders before 3 PM CST. Standard delivery 2-5 business days, express options available at checkout. 30-day hassle-free returns on uninstalled parts — free return shipping included. 1-year OEM factory warranty coverage.