OEM Carrier 40VA Control Transformer for Model C50A404052

This OEM Carrier transformer (part number HT01BD236) is the factory-specified replacement for the C50A404052 packaged unit. The transformer steps down 120V line voltage to the 24V signal required by your thermostat, control board, contactor coil, and all low-voltage safety circuits. When this component fails, the entire control circuit goes dark — the thermostat shows no power, the system refuses to respond to any call for heating or cooling, and no fault codes appear because there is no voltage to generate them.

• Specs: 40VA output rating | 120V primary / 24V secondary | Class 2 control transformer | OEM part number HT01BD236 | Factory-matched for Carrier C50A404052
• OEM vs Generic: This is a genuine OEM Carrier transformer wound to exact factory tolerances. Generic transformers may carry insufficient VA capacity under full load, causing nuisance tripping of built-in breakers and premature failure — a common callback for technicians who substitute off-brand units.
• Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (verify 0V before touching wires), wire stripper. Document or photograph all low-voltage wiring before disconnecting terminals. Secure all wire nuts fully after reinstallation and verify 24V output before closing the cabinet.
• Warranty: 1-year OEM factory warranty against manufacturing defects. In-stock and ships same business day from our climate-controlled warehouse.

Compatibility: Designed specifically for the Carrier C50A404052 commercial packaged rooftop unit. Always verify your unit's data plate confirms 120V primary input and 40VA 24V secondary requirement before ordering. Our parts specialists are available to confirm fitment — contact us before you order if you have any questions.