OEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP002 for Model TCHC2550HECMRLY500

This is the genuine OEM Carrier Direct Spark Ignition (DSI) control board, part number LH33WP002, factory-specified for the Carrier TCHC2550HECMRLY500. The DSI control board is the brain of your heating system — it sequences the ignition cycle, energizes the spark igniter and gas valve, monitors flame sensing, and manages blower motor timing. When this board fails, common symptoms include a hard lockout with no ignition attempt, repeated ignition retries without flame establishment, a system that fires briefly then shuts down, or a complete no-heat condition with fault codes stored in the control.

• Part Specs: Direct Spark Ignition (DSI) microprocessor-based control board | OEM Part # LH33WP002 | Replaces: LH33WP002A | Controls combustion sequencing, spark igniter, gas valve, blower motor, and flame sensing/lockout logic
• OEM vs. Generic: This is a genuine Carrier OEM board — factory-programmed with exact timing parameters, lockout thresholds, and safety sequencing for your unit. Aftermarket boards may use approximated firmware that causes nuisance lockouts, improper blower delays, or voided equipment warranties.
• Install Difficulty: 3/5 — Requires shutting off power and gas supply before servicing. Photograph all wiring harness connections prior to disconnecting. Tools needed: Phillips-head and flat-head screwdrivers, needle-nose pliers, a multimeter for verifying 24V control circuit integrity post-install. Recommended for experienced DIYers or licensed HVAC technicians.
• Warranty & Shipping: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse when ordered before cutoff.

Compatibility: Designed for the Carrier TCHC2550HECMRLY500. This board is also used across select Carrier, Bryant, and Payne packaged and split-system models in the 48, 574, 580, 581, 582, 583, 588, and 589 series — always verify your unit's data plate and existing part number before ordering. Our fitment team is available to confirm compatibility before you purchase.