OEM Carrier Transformer 40VA 120V–24V for Model FX4ANF048000ACAA

This OEM replacement transformer (part number HT01CN236) is the factory-specified control circuit transformer for the Carrier FX4ANF048000ACAA fan coil air handler. Its job is to step down 120V line voltage to the 24V signal voltage that powers your thermostat, contactor coil, and all low-voltage control wiring. When the transformer fails — commonly due to a shorted control wire, overloaded secondary circuit, or age — absolutely nothing in the system responds. The thermostat goes blank, the air handler won't start, and no fault codes are generated because the control board itself has no power.

• Specs: 40VA rating | Primary: 120VAC | Secondary: 24VAC | Factory OEM part number HT01CN236 | Designed and tested to Carrier factory tolerances
• OEM vs Generic: OEM transformers are wound and insulated to the exact VA and thermal ratings required by this air handler's control board. Undersized generic units can overheat, trip their internal breaker repeatedly, or fail prematurely under normal thermostat current draw.
• Install difficulty: 2/5 — Shut off power at the breaker and verify with a non-contact voltage tester before touching any wiring. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Photograph all wiring connections before disconnecting. Check all low-voltage wiring for shorts before powering back up — a shorted wire is the most common cause of transformer failure and will burn out a new unit immediately if not corrected first.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our climate-controlled warehouse.

Compatibility: Engineered as a direct OEM replacement for the Carrier FX4ANF048000ACAA 4-ton fan coil air handler. Verify primary voltage (120V) and secondary voltage (24V) on your unit's data plate before ordering. Our HVAC parts specialists are available to confirm fitment prior to purchase — same-day shipping on all in-stock orders.