OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY3PNA048090NA

This is the factory OEM Direct Spark Ignition (DSI) control board for the Carrier PY3PNA048090NA packaged rooftop unit. As the central intelligence of your system's heating sequence, the DSI control board manages combustion, blower and indoor motors, the spark igniter, and the gas valve — while simultaneously monitoring ignition trial timing, flame sensing, and safety lockout logic. When this board fails, you'll typically experience a no-heat condition, repeated ignition lockouts, erratic blower behavior, or a system that starts then shuts down before completing the heating cycle.

• Specs: Microprocessor-based Direct Spark Ignition (DSI) board | OEM Part # LH33WP003 | Also supersedes LH33WP003A | Engineered for Carrier/Bryant commercial packaged rooftop applications
• OEM vs Generic: OEM boards are factory-programmed with exact trial-for-ignition timing and lockout sequences specific to Carrier equipment. Aftermarket boards may use generalized firmware that can cause nuisance lockouts or fail to meet manufacturer safety specifications.
• Install Difficulty: 3/5 — Requires isolation of 24V control circuit and 115V supply before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter, and wiring diagram (located inside unit access panel). Always photograph all wiring harness connections before removal.
• Warranty: 1-year OEM manufacturer warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered as the direct OEM replacement for Carrier model PY3PNA048090NA packaged rooftop units. Verify the OEM part number stamped on your existing board before ordering. Compatible with both LH33WP003 and LH33WP003A board revisions. Questions about fitment? Our HVAC parts specialists confirm compatibility before you order — contact us today and get your system back online fast.