OEM Carrier Control Transformer 40VA for Model C4850C50ZG090610

This is the OEM factory-replacement control transformer (part number HT01BD236) for the Carrier C4850C50ZG090610 packaged unit. The transformer steps down 120V line voltage to 24V AC to power the low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When the transformer fails, the entire control circuit goes dead: the thermostat goes blank, no heating or cooling calls are answered, and the system appears completely unresponsive at the stat. A failed transformer is often misdiagnosed as a bad thermostat or control board, making correct identification critical before replacing costlier components.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | Class 2 control circuit transformer | Direct OEM replacement for part number HT01BD236
• OEM vs Generic: This OEM transformer is wound and rated to exact Carrier factory specifications. Generic alternatives frequently use undersized VA ratings that cause nuisance tripping under normal load — especially when multiple 24V accessories (humidifiers, zone boards, UV lights) share the circuit.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify with a non-contact voltage tester before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label all wire connections before removing the old transformer. Total replacement time is typically 20–30 minutes.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. In-stock units ship same business day when ordered before 3PM local time.

Compatibility: Designed for the Carrier C4850C50ZG090610 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit's data plate or wiring diagram before ordering. If you are unsure of fitment, our HVAC parts specialists are available to confirm compatibility before you purchase — no guesswork required.