OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY1RJA060115AAWB

This is the factory OEM Direct Spark Ignition (DSI) control board for the Carrier PY1RJA060115AAWB packaged gas/electric unit. As the brain of the heating system, this microprocessor-based board controls combustion sequencing, manages blower and indoor motor timing, fires the spark igniter, operates the gas valve, and continuously monitors flame sensing and safety lockout logic. When this board fails, symptoms typically include a no-heat condition, repeated ignition lockout faults, short cycling, or a furnace that sparks but never lights — or one that lights briefly and immediately shuts down.

• OEM Part Number: LH33WP003 (also supersedes LH33WP003A) | Direct Spark Ignition (DSI) board | Factory-specified for Carrier PY1RJA060115AAWB packaged units
• Function & Features: Microprocessor-based DSI control; manages trial-for-ignition timing, flame-sensing rod monitoring, blower motor on/off delays, and automatic safety lockout with fault code output
• OEM vs Generic: Genuine Carrier OEM boards are pre-programmed with exact timing parameters for your unit. Aftermarket boards may use generic timing profiles that cause nuisance lockouts, reduced efficiency, or premature heat exchanger stress — always specify OEM for commercial packaged equipment.
• Install Difficulty: 3/5 — Disconnect power and gas before servicing. Tools needed: 1/4" and 5/16" nut drivers, needle-nose pliers, phone/camera to photograph all wiring harness connections before removal. Transfer wiring connector by connector. Verify all harness clips are fully seated before restoring power.
• Warranty: 1-year OEM factory warranty. In stock — ships same business day from our warehouse.

Compatibility: Designed as the factory-specified DSI control board for the Carrier PY1RJA060115AAWB packaged gas/electric unit. Verify your existing board's part number (LH33WP003 or LH33WP003A) against the unit data plate before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before you buy — contact us today and we'll confirm compatibility fast.