OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY3PPA048130AB

This is the OEM factory-specified Direct Spark Ignition (DSI) Control Board for the Carrier PY3PPA048130AB packaged rooftop gas/electric unit. As the brain of the heating system, this microprocessor-based board orchestrates the entire combustion sequence — it controls the spark igniter, gas valve, combustion blower, and indoor fan motor while continuously monitoring flame sensing, safety inputs, and timed lockout logic. When this board fails, symptoms include no-heat calls, ignition lockout fault codes, failure to advance past the trial-for-ignition stage, or erratic blower behavior that persists even after resetting the system.

• OEM Part Number: LH33WP003 (also supersedes LH33WP003A) | Factory-direct Carrier replacement | Microprocessor-based DSI logic board
• OEM vs Generic: This OEM board is programmed to Carrier's exact timing sequences, flame-sense thresholds, and lockout parameters for the PY3PPA048130AB. Aftermarket boards may use generalized DSI logic that can cause nuisance lockouts or fail to meet unit-specific safety timing windows.
• Install Difficulty: 3/5 — Involves high-voltage wiring and gas-system safety interlocks. Disconnect power and gas before servicing. Tools needed: 1/4" and 5/16" nut drivers, needle-nose pliers, multimeter, smartphone to photograph existing wiring. Recommend licensed HVAC technician for this repair.
• Warranty: 1-year OEM factory warranty. Ships same business day from our stocked warehouse.

Compatibility: Engineered as the direct OEM replacement for Carrier model PY3PPA048130AB packaged rooftop units. Always verify your existing board's part number against LH33WP003 or LH33WP003A before ordering. Not sure? Our HVAC parts specialists confirm fitment before you buy — contact us with your full model and serial number.