OEM Carrier Transformer 40VA 120V–24V for Model FX4DNF019T00AAAA

This is the factory OEM replacement transformer (part number HT01CN241) for the Carrier FX4DNF019T00AAAA fan coil air handler. The transformer steps line voltage (120V) down to the 24V control circuit voltage that powers your thermostat, contactor coil, and all low-voltage control signals. When this component fails, the entire control circuit goes dead — the thermostat goes blank, the system refuses to respond to any command, and no heating or cooling call is executed. It is often the first component to inspect when nothing in the system appears to respond.

• Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01CN241 | Factory-matched for Carrier FX4DNF019T00AAAA air handler
• OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage specifications. Generic transformers can under-deliver on VA capacity under load, causing nuisance low-voltage dropouts, erratic thermostat behavior, and premature contactor coil failure.
• Install difficulty: 2/5 — Shut off all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter, wire nuts. Label all wires before disconnecting. Verify incoming voltage at primary leads with a multimeter before energizing.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed and factory-spec'd for the Carrier FX4DNF019T00AAAA fan coil air handler. Always confirm your unit's data plate matches the part number HT01CN241 before ordering. Have questions about fitment? Our HVAC parts specialists verify compatibility before you buy — reach out before placing your order.