OEM Carrier Transformer 40VA 120V/24V for Model C50A406052

This OEM replacement transformer (part number HT01BD236) is the factory-specified step-down transformer for the Carrier C50A406052 packaged unit. The transformer converts 120V line voltage to the 24V AC signal that powers the entire control circuit — including the thermostat, contactor coil, gas valve, and control board. When the transformer fails, absolutely nothing responds: the thermostat goes blank, the system won't call for heating or cooling, and no components energize. It is often the first component to check when a system appears completely dead with no obvious cause.

• Specs: 40VA rating | 120V primary / 24V secondary | Compatible with single-stage and multi-stage control circuits | Factory-matched OEM part number HT01BD236
• OEM vs Generic: OEM transformers are wound and insulated to Carrier's exact VA and thermal specifications. Generic units may be under-rated on VA capacity, leading to overheating, nuisance tripping of the internal fuse, and shortened service life — especially on systems with high 24V circuit loads.
• Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Verify 0V at primary terminals before handling. Label all low-voltage wiring before disconnecting. Check for a shorted 24V circuit (stuck contactor coil, grounded wire) before replacing — a short will blow the new transformer immediately.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C50A406052 commercial packaged rooftop unit. Always confirm your unit's control voltage and VA requirements on the data plate before ordering. If you're unsure of fitment, our HVAC parts specialists are available to verify compatibility before you purchase. Order now — in stock and ready to ship today.