OEM Carrier Transformer 40VA 120V to 24V for Model FV4CNF002000AAAA

This is the OEM factory-replacement transformer (part number HT01CN236) designed specifically for the Carrier FV4CNF002000AAAA fan coil air handler. The transformer steps down 120V line voltage to the 24V signal voltage required to power the control board, thermostat, and all low-voltage control circuit components. When this transformer fails, the entire control circuit goes dark — your thermostat will be unresponsive, the air handler will not run, and no error codes will display because the board itself has no power.

• Specs: 40VA rating | 120V primary input | 24V secondary output | Hardwired lead connections | Factory-matched electrical characteristics for Carrier FV4CNF002000AAAA
• OEM vs Generic: The OEM HT01CN236 transformer is wound to Carrier's exact VA rating and insulation class, ensuring stable 24V output under full control circuit load. Generic transformers with undersized VA ratings can sag under load, causing erratic thermostat behavior and premature control board failure.
• Install difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, needle-nose pliers, multimeter. Label and photograph all wiring connections before removing the old transformer. Verify 24V output with a multimeter after installation before restoring full power.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our stocked warehouse.

Compatibility: Engineered as a direct OEM replacement for the Carrier FV4CNF002000AAAA fan coil air handler. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit's data plate or wiring diagram before ordering. Our parts specialists are available to confirm fitment — order with confidence and get back to comfort fast.