OEM Carrier 40VA Control Transformer for Model FX4DNB049L00ACAA — Part# HT01CN241

This OEM replacement transformer (part number HT01CN241) is the factory-specified control circuit transformer for the Carrier FX4DNB049L00ACAA fan coil air handler. The transformer steps down line voltage (120V) to 24V AC to power the low-voltage control circuit — including the thermostat, relays, and control board. When the transformer fails, the entire control circuit goes dead: the thermostat shows no power, the system won't respond to any call for heating or cooling, and nothing operates. A blown transformer is often the first sign of a wiring short elsewhere in the low-voltage circuit, so always inspect wiring before replacing.

• Specs: 40VA capacity | 120V primary / 24V secondary | Class 2 rated | Factory-matched design for Carrier FX4DNB049L00ACAA air handler control circuits
• OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage tolerances. Generic transformers often run undersized at true load, causing voltage sag that triggers nuisance lockouts and premature control board failure.
• Install Difficulty: 2/5 — Shut off power at the breaker and verify with a multimeter before touching any terminals. Tools needed: flathead and Phillips screwdriver, multimeter, wire nuts or spade connectors. Check for shorted low-voltage wiring before energizing the new transformer to prevent immediate failure.
• Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier FX4DNB049L00ACAA fan coil air handler. Always verify your unit's data plate and existing transformer VA/voltage ratings before ordering. Our fitment team is available to confirm compatibility before you buy — no guesswork, no returns.