OEM Carrier Transformer 40VA 120V/24V for Model FF1DNA024005ABAA

This is the factory OEM replacement transformer (part number HT01CN236) for the Carrier FF1DNA024005ABAA air handler. The transformer steps down line voltage from 120V to the 24V AC signal that powers your control board, thermostat, and all low-voltage safety circuits. When this component fails, nothing responds — the thermostat goes blank, the system won't call for heating or cooling, and the control board appears completely dead. It is one of the first components to check when your system shows zero activity despite power being present at the unit.

• Specs: 40VA rated | 120V primary / 24V secondary | Factory-matched OEM output tolerance | Direct drop-in replacement for part number HT01CN236
• OEM vs Generic: OEM transformers are wound to exact VA and voltage specifications for the Carrier control circuit. Undersized or off-tolerance generic transformers can cause nuisance tripping, board damage, or repeated blown fuses in the 24V circuit.
• Install difficulty: 2/5 — Shut off all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to confirm 24V output after installation). Label or photograph all wiring connections before removing the old transformer.
• Warranty: 1-year OEM factory warranty. In-stock units ship same business day from our warehouse when ordered before cutoff.

Compatibility: Engineered specifically for the Carrier FF1DNA024005ABAA air handler. Always verify your existing transformer's VA rating and primary/secondary voltages on the data plate or wiring diagram before ordering. Our fitment team is available to confirm compatibility before you purchase — just reach out with your model and serial number.