OEM Carrier Transformer 40VA 120V–24V for Model FA4CNC030008AAAA

This is the factory OEM replacement transformer (part# HT01CN241) for the Carrier FA4CNC030008AAAA air handler. The transformer steps down line voltage (120V) to the 24V AC control circuit voltage that powers your thermostat, contactor coil, and control board. When it fails, the entire control circuit goes dead — your thermostat goes blank, the system won't respond to calls for heating or cooling, and no safety circuits can operate. It's one of the most overlooked but critical components in any air handler.

• Specs: 40VA rating | 120V primary input | 24V AC secondary output | Mounts directly to factory bracket | OEM part number HT01CN241
• OEM vs Generic: This OEM Carrier transformer is wound to exact factory VA and voltage specifications. Undersized generic transformers can overheat under full control-circuit load — especially when multiple accessories (humidifiers, UV lights, zoning boards) share the 24V circuit — leading to premature failure or nuisance tripped fuses.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flat-head and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph existing wiring before disconnecting. Verify 24V output with a multimeter after installation before restoring full power.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Designed specifically for the Carrier FA4CNC030008AAAA fan coil air handler. Always verify your existing transformer's VA rating and voltage markings on the unit data plate before ordering to ensure an exact match. If your system has added accessories drawing 24V power, confirm total VA load does not exceed 40VA. Our parts specialists are available to confirm fitment — reach out before you order if you have any questions.