OEM Carrier 40VA Control Transformer for Model FA4ANF024005AFAA

This OEM control transformer (part# HT01CN236) is the factory-specified replacement for the Carrier FA4ANF024005AFAA 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 switching circuits. When this component fails, the entire control circuit goes dead — your thermostat goes blank, the system won't respond to any commands, and no heating or cooling function can be initiated. It is often the first component to inspect when a system shows absolutely no signs of life despite the breaker being on.

• Specs: 40VA rated | Primary: 120V AC | Secondary: 24V AC | Industry-standard footprint | Factory-matched impedance for stable voltage output under full control load
• OEM vs Generic: The OEM HT01CN236 transformer is wound to Carrier's exact VA and impedance specification, ensuring stable 24V output even under peak load from multiple control relays. Generic transformers with loose tolerances can undervolt the control board, causing erratic lockouts and premature board failure.
• Install difficulty: 2/5 — Shut off power at the breaker and verify voltage is absent with a multimeter before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Photograph or label all low-voltage wire connections before disconnecting. Re-verify 24V output at secondary terminals after installation.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. In-stock and ships same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for the Carrier FA4ANF024005AFAA fan coil air handler. Confirm your existing transformer's VA rating and primary/secondary voltages on the unit data plate or wiring diagram before ordering. Our parts team is available to verify fitment — order with confidence and get your system back online fast.