OEM Carrier Control Transformer 40VA for Model C4850C50Z3060500

This is the factory OEM replacement control transformer (part# HT01BD236) for the Carrier C4850C50Z3060500 packaged unit. The transformer steps down 120V line voltage to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When it fails, absolutely nothing responds: the thermostat goes blank, the system won't call for heating or cooling, and you may measure zero volts on the secondary side. A shorted transformer will often trip its internal thermal fuse or blow the control-circuit fuse.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | Foot-mount bracket | OEM part number HT01BD236 | Factory-matched to Carrier C4850C50Z3060500 electrical specifications
• OEM vs Generic: The OEM transformer is wound to exact VA and voltage tolerances required by the Carrier control board. Undersized or off-tolerance generic transformers overheat under peak load, causing nuisance lockouts and shortened service life — especially in packaged units running simultaneous heating and cooling control loads.
• Install difficulty: 2/5 — Disconnect power at the disconnect box and verify zero voltage with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter, wire nuts or spade connectors. Photograph all wiring connections before disconnecting. Primary wires connect to line voltage; secondary wires feed the 24V control circuit — do not reverse.
• Warranty: 1-year OEM factory warranty. In-stock units ship same business day when ordered before 3 PM local time.

Compatibility: Engineered specifically for the Carrier C4850C50Z3060500 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering. If your breaker trips or fuse blows immediately upon power-up, inspect the downstream 24V wiring for shorts before installing a new transformer. Our parts specialists are available to confirm fitment — reach out before you order.