OEM Carrier 40VA Control Transformer for Model FB4CNF048000ACAA Air Handler

This is the factory OEM replacement transformer (part number HT01CN241) for the Carrier FB4CNF048000ACAA fan coil air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers your control board, thermostat, and all low-voltage safety circuits. When this component fails, the entire control circuit loses power — resulting in a completely unresponsive thermostat, a blank display, or a system that won't heat, cool, or respond to any commands. A failed transformer is often misdiagnosed as a bad control board, so always verify 24V output at the secondary terminals before replacing more expensive components.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | Direct OEM replacement | Factory part number HT01CN241
• OEM vs Generic: This OEM unit is wound and insulated to Carrier's exact factory specifications, ensuring precise 24V output under load. Generic transformers may sag voltage under full circuit demand, causing intermittent lockouts, nuisance tripping, or premature control board failure.
• Install difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Verify 0V at primary terminals before handling. Photograph all wiring connections before disconnecting the old unit.
• Warranty: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier FB4CNF048000ACAA 4-ton fan coil air handler. Confirm your unit's data plate shows a 120V primary / 24V secondary, 40VA control transformer before ordering. Our HVAC parts specialists are available to verify fitment — reach out before you order if you have any questions.