OEM Carrier Transformer 40VA 120V/24V for Model C4850C48ZG070500

This OEM replacement transformer (part number HT01BD236) is the factory-specified control circuit transformer for the Carrier C4850C48ZG070500 packaged unit. The transformer steps down line voltage from 120V to the 24V required to power the control board, thermostat, and all low-voltage control circuits. When this component fails, the entire control system goes dark — the thermostat loses power, the system becomes completely unresponsive, and no heating or cooling function can be initiated. A failed transformer is one of the most commonly misdiagnosed faults in packaged equipment, often mistaken for a bad control board.

• Specs: 40VA rated | 120V primary / 24V secondary | OEM part number HT01BD236 | Factory-matched output tolerance for stable control circuit voltage
• OEM vs Generic: This OEM unit is wound to exact Carrier factory specifications, ensuring stable 24V output under full control circuit load. Generic transformers often under-deliver VA capacity, causing erratic board behavior, nuisance lockouts, and premature contactor coil failure.
• Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Verify output voltage (should read 24–28VAC unloaded) before reinstalling panels. Always check for a shorted control circuit as the root cause of transformer failure before installing the new unit.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Engineered specifically for the Carrier C4850C48ZG070500 packaged unit. Cross-reference OEM part number HT01BD236 against your unit's wiring diagram and data plate before ordering. If your transformer shows signs of burning, always inspect the 24V control circuit for shorts before replacement. Our team is available to verify fitment — order with confidence and receive fast, same-day shipping.