OEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C48ZG060500

This OEM replacement control transformer (part number HT01BD236) is the factory-specified unit for the Carrier C4850C48ZG060500 packaged system. The transformer steps down 120V line voltage to the 24V signal used by the thermostat, contactor coils, control board, and all low-voltage safety circuits. When this transformer fails, the entire control circuit goes dead — the thermostat displays nothing, the system won't respond to calls for heating or cooling, and no safety faults can be communicated. A failed transformer is often misdiagnosed as a bad thermostat or control board, making it one of the first components to verify during a no-power diagnostic.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched impedance and thermal protection
• OEM vs Generic: This OEM transformer is wound to exact Carrier factory specifications with built-in thermal cutoff protection. Generic transformers frequently lack proper VA ratings or thermal fusing, risking downstream control board damage under surge or short-circuit conditions.
• Install difficulty: 2/5 — Shut off all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or terminal connectors. Label all low-voltage wiring before disconnecting. Confirm 24V output at secondary terminals after installation before restoring full system power.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C4850C48ZG060500 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages against your unit's wiring diagram before ordering. Our technical team is available to confirm fitment prior to purchase — same-day shipping on all in-stock orders.