OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY1PPB048090ABAA

This is the genuine OEM Direct Spark Ignition (DSI) control board for the Carrier PY1PPB048090ABAA packaged gas/electric unit, sold under Carrier part number LH33WP003. The DSI control board is the nerve center of your system's combustion sequence — it controls and sequences the spark igniter, gas valve, blower motor, and inducer motor while continuously monitoring flame sensing, ignition trial timing, and safety lockout conditions. When this board fails, common symptoms include a hard lockout with no ignition attempt, intermittent no-heat calls, failure to prove flame, or the unit cycling off immediately after the gas valve opens.

• Part Type: Direct Spark Ignition (DSI) Control Board | Microprocessor-based combustion sequencer | OEM Part # LH33WP003 (also supersedes LH33WP003A)
• OEM vs Generic: The factory OEM board is pre-programmed with Carrier's exact ignition timing, trial-for-ignition duration, and lockout thresholds. Aftermarket boards may use generic timing curves that can cause nuisance lockouts or mask real flame-sensing issues — always prefer OEM on commercial packaged units.
• Install Difficulty: 3/5 — Requires disconnecting 24V control wiring, line-voltage blower and inducer leads, and the gas valve harness. Document all wiring with photos before removal. Tools needed: 1/4" and 5/16" nut drivers, needle-nose pliers, a multimeter for verifying 24V signal integrity post-install. Always shut off gas and power before beginning.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier PY1PPB048090ABAA packaged unit. This board also supersedes the LH33WP003A revision. Verify the part number on your existing board's label before ordering. Need fitment confirmation? Our HVAC parts specialists verify compatibility before you buy — contact us before placing your order.