OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY3PNA042090AA

This is the factory OEM Direct Spark Ignition (DSI) control board for the Carrier PY3PNA042090AA packaged heating and cooling unit. The DSI control board is the central brain of the furnace/heating section — it sequences the ignition trial, monitors flame sense feedback, controls the inducer and blower motor timings, and enforces safety lockout logic. When this board fails, common symptoms include a no-heat condition with repeated ignition lockout, erratic burner cycling, failure to prove flame even when the igniter and flame sensor are known-good, or a complete lack of response from the heating circuit despite 24V control power being present.

• Specs: Direct Spark Ignition (DSI) control | OEM Part Number: LH33WP003 | Factory-matched board for Carrier PY3PNA042090AA | 24V control voltage input | Integrated safety lockout and retry logic
• OEM vs Generic: This is a genuine OEM Carrier board — factory-programmed with the exact ignition timing, timed-off delays, and lockout sequences required by the PY3PNA042090AA. Aftermarket boards may use generic timing profiles that cause nuisance lockouts or void equipment warranties.
• Install Difficulty: 3/5 — Requires safely disconnecting 24V and line-voltage wiring harnesses. Tools needed: ¼" nut driver, needle-nose pliers, multimeter, and camera/phone to photograph all connector positions before removal. Always shut off gas supply and disconnect power at the disconnect box before servicing. If uncertain, consult a licensed HVAC technician.
• Warranty: 1-year OEM factory warranty against defects. Orders ship same business day when placed before 3PM local time.

Compatibility: Engineered and factory-specified for Carrier model PY3PNA042090AA. Verify the OEM part number LH33WP003 against your unit's wiring diagram or data label before ordering. Our HVAC parts specialists are available to confirm fitment — contact us before you order if you have any questions. In stock and ready to ship today.