OEM Carrier Transformer 40VA 120V/24V for Model C4850C50Z3105610

This is the factory OEM replacement transformer (part number HT01BD236) for the Carrier C4850C50Z3105610 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage required by your thermostat, control board, and all low-voltage safety and switching circuits. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any call for heating or cooling, and no contactors or relays will energize. It is often one of the first components to check when a system shows absolutely no response despite confirmed line power at the unit.

• Specs: 40VA rated | 120V primary / 24V secondary | OEM part number HT01BD236 | Factory-matched output for Carrier packaged unit control circuits
• OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage specifications. Undersized or off-tolerance generic transformers can overload under peak demand, blow internal fuses, or cause erratic low-voltage behavior — shortening control board life.
• Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flathead and Phillips screwdriver, wire stripper, multimeter, needle-nose pliers. Always verify 0V at primary terminals before handling. Photo all wire connections before removal.
• Warranty: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier C4850C50Z3105610 packaged unit. Confirm your existing transformer's VA rating and primary/secondary voltages on the data plate or wiring diagram before ordering. Our fitment specialists are available to verify compatibility before you purchase — no guesswork required.