OEM Carrier Transformer 40VA 120V–24V for Model FA4ANC042010AGAA

This is the factory OEM replacement transformer (part number HT01CN236) for the Carrier FA4ANC042010AGAA air handler. The transformer steps down line voltage from 120V to 24V to power the low-voltage control circuit — including the thermostat, control board, and all system relays. When the transformer fails, the entire control circuit goes dead: your thermostat goes blank, the system won't respond to any calls for heating or cooling, and nothing turns on. It is often the first component to inspect when a unit appears completely unresponsive despite having line power present.

• Specs: 40VA rated | 120V primary / 24V secondary | OEM part number HT01CN236 | Factory-matched output for Carrier low-voltage control circuits
• OEM vs Generic: This OEM transformer is wound and insulated to Carrier's exact factory specification, ensuring stable 24V output under load. Generic transformers frequently deliver inconsistent voltage, causing nuisance lockouts, erratic thermostat behavior, and premature control board failure.
• Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Verify 0V at both primary terminals before touching wiring. Label or photograph all low-voltage wiring connections prior to removal.
• Warranty: 1-year OEM factory warranty included. In stock and ships same business day from our climate-controlled warehouse.

Compatibility: Designed specifically for the Carrier FA4ANC042010AGAA air handler. Always verify your existing transformer's VA rating and voltage markings on the unit data plate before ordering to confirm fitment. Our HVAC parts specialists are available to verify compatibility before you order — order with confidence and get your system back online today.