OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY3GNA048090NB

This is the genuine OEM Carrier LH33WP003 Direct Spark Ignition (DSI) Control Board — the factory-specified replacement for the Carrier PY3GNA048090NB packaged rooftop unit. The DSI control board is the central brain of your unit's heating system: it sequences spark ignition, opens and closes the gas valve, controls combustion blower and indoor fan motors, and continuously monitors flame sensing to ensure safe operation. When this board fails, you'll typically experience a complete no-heat condition, repeated ignition lockout codes, or a system that sparks but never sustains a flame.

• Specs: Direct Spark Ignition (DSI) microprocessor-based control | Manages spark igniter, gas valve, combustion blower, and indoor fan motor | LED status indicators for fault code diagnostics | Factory-matched to Carrier OEM specifications
• OEM vs Generic: This is a genuine Carrier OEM board engineered to original design tolerances, ensuring full compatibility with all safety interlocks, timing sequences, and fault logic in the PY3GNA048090NB. Aftermarket boards may have mismatched timing or diagnostic codes that cause nuisance lockouts.
• Install Difficulty: 3/5 — Disconnect power at the disconnect box before beginning. Document all wiring connections with photos before removal. Tools needed: ¼" nut driver, Phillips screwdriver, needle-nose pliers. Always restore power and run a full heat cycle to verify proper flame-sensing operation after installation.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our warehouse.

Compatibility: Designed for the Carrier PY3GNA048090NB packaged rooftop gas/electric unit. Also compatible with select Carrier, Bryant, and Payne rooftop models using the LH33WP003 control board — verify your unit's data plate and existing board part number before ordering. Need fitment confirmation? Our HVAC parts specialists are standing by to verify compatibility before you purchase.