OEM Carrier Control Transformer 40VA 120V/24V for Model FV4CNF003T00AAAA

This is the OEM factory-replacement control transformer (part number HT01CN236) for the Carrier FV4CNF003T00AAAA fan coil air handler. The transformer steps down line voltage (120V) to the 24V AC signal used by your thermostat, control board, contactor coil, and all low-voltage control circuits. When this transformer fails, the entire control circuit goes dead — the thermostat shows no response, the system won't call for heating or cooling, and no fault codes will display because the board itself has lost power.

• Specs: 40VA rating | 120V primary / 24V secondary | Class 2 low-voltage output | OEM part number HT01CN236 | Factory-matched for Carrier FV4CNF003T00AAAA air handlers
• OEM vs Generic: OEM transformers are wound and rated to exact factory specifications, ensuring stable 24V output under full control circuit load. Generic units often underperform at rated VA, causing nuisance tripping of internal thermal protectors and shortened service life.
• Install Difficulty: 2/5 — Disconnect power at the breaker before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (verify 0V before touching terminals). Wire leads are typically spade or screw-terminal connections — photograph all wiring before removal.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our climate-controlled warehouse.

Compatibility: Designed as a direct OEM replacement for the Carrier FV4CNF003T00AAAA fan coil air handler. Always verify the transformer's VA rating and primary/secondary voltages on your unit's data plate before ordering to confirm fitment. Have questions about compatibility? Our HVAC parts specialists verify fitment before you order — reach out before you buy.