OEM Carrier Transformer 40VA 120V to 24V for Model FV4CNF005L00ABAA

This OEM replacement transformer (part# HT01CN236) is the factory-specified control circuit transformer for the Carrier FV4CNF005L00ABAA fan coil air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, and all low-voltage control components. When this transformer fails, the result is total system unresponsiveness — the thermostat goes blank, the air handler won't respond to calls for heating or cooling, and nothing powers on despite the unit having line voltage. It is one of the most commonly overlooked failure points in any air handler diagnosis.

• Specs: 40VA rated | 120V primary / 24V secondary | Class 2 transformer | OEM part number HT01CN236 | Factory-matched for Carrier FV4CNF005L00ABAA
• OEM vs Generic: OEM transformers are wound and rated to exact factory VA specifications, ensuring stable 24V output under full control circuit load. Undersized or off-tolerance generic units can sag voltage, causing intermittent lockouts, nuisance faults, and premature control board failure.
• Install Difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdriver, multimeter, wire nuts or spade connectors. Verify 0V at primary terminals before touching wiring. Photograph all connections before removal.
• Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship the same business day from our warehouse.

Compatibility: Designed specifically for the Carrier FV4CNF005L00ABAA fan coil air handler. Verify your existing transformer's VA rating and primary/secondary voltages on the unit's wiring diagram or data plate before ordering. If you are unsure of fitment, our parts specialists can confirm compatibility before you purchase. In stock and ready to ship today — get your system back online fast.