OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY1RPA120180ABWA

This is the genuine OEM Carrier Direct Spark Ignition (DSI) control board, part number LH33WP003, factory-specified for the Carrier PY1RPA120180ABWA packaged rooftop unit. The DSI control board is the operational brain of your heating system — it manages spark ignition sequencing, gas valve activation, combustion blower and indoor fan motor control, flame sensing, and safety lockout logic. When this board fails, common symptoms include a complete no-heat condition, ignition attempts with immediate lockout, the system starting then shutting off within seconds, or persistent fault codes displayed on the unit's LED diagnostic indicators. Replacing with a genuine OEM board — not a generic substitute — ensures factory-matched timing sequences, proper lockout thresholds, and full compatibility with all connected safety controls.

• Part Type: Direct Spark Ignition (DSI) Integrated Control Board | Microprocessor-based | LED fault-code diagnostics | Controls spark igniter, gas valve, blower, and indoor fan motors
• OEM vs Generic: This is a factory-authorized OEM board engineered to Carrier's original design specifications. Generic aftermarket boards may have mismatched ignition timing or lockout sequences, risking nuisance trips, voided equipment warranties, and potential safety hazards on commercial rooftop equipment.
• Install Difficulty: 3/5 — Shut off gas supply and disconnect power at the disconnect box before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, phone/camera to photograph all wiring harness connections before removal. Label every connector. We strongly recommend licensed HVAC technician installation on commercial rooftop units.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our climate-controlled warehouse.

Compatibility: Designed for the Carrier PY1RPA120180ABWA packaged rooftop unit. Always cross-reference your unit's data plate model number and the part number printed on your existing board before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before you purchase — contact us anytime.