OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY3PNA042060AB

This is the genuine OEM Carrier LH33WP003 Direct Spark Ignition (DSI) Control Board, the factory-specified replacement for the Carrier PY3PNA042060AB packaged unit. As the brain of the heating system, this microprocessor-based board orchestrates every stage of the ignition sequence — commanding the spark igniter, opening the gas valve, monitoring flame sensing, and timing the blower and inducer motors. When this board fails, symptoms include persistent ignition lockout, failure to ignite after the trial period, erratic blower operation, or a complete no-heat condition with no error codes responding normally.

• Part Number: LH33WP003 (also supersedes LH33WP003A) | Direct Spark Ignition (DSI) type | Microprocessor-based logic board | Factory-matched for Carrier PY3PNA042060AB
• OEM vs Generic: The genuine OEM board ensures exact timing parameters for ignition trial, lockout thresholds, and flame-sense sensitivity. Aftermarket boards may use wider tolerances, risking nuisance lockouts or unsafe fault-handling behavior.
• Install Difficulty: 3/5 — Disconnect power and gas before servicing. Document all wiring harness connections with photos before removal. Tools needed: 1/4" nut driver, flathead screwdriver, needle-nose pliers, and a multimeter for pre/post verification. We recommend a licensed HVAC technician for this repair.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our warehouse when ordered before 3 PM EST.

Compatibility: Engineered for the Carrier PY3PNA042060AB packaged unit. This board also fits select Carrier, Bryant, Payne, and Day & Night rooftop and packaged gas units that utilize the LH33WP003/LH33WP003A DSI control. Always verify your existing board's part number against your unit's data plate before ordering. Not sure it fits? Contact our HVAC parts specialists — we verify fitment before you buy.