OEM Carrier 40VA Control Transformer HT01BD236 for Model C48A304051

This OEM control transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C48A304051 packaged unit. The transformer steps down line voltage (120V) to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When this component fails, the system will appear completely unresponsive: the thermostat goes dark, the contactor won't energize, and nothing happens at the unit regardless of demand. A blown transformer is often caused by a wiring short in the 24V circuit, so always inspect for shorted wires or a failed component before replacing.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched output for reliable control circuit operation
• OEM vs Generic: This OEM transformer is wound to Carrier's exact VA rating and insulation class, ensuring stable 24V output under full control-circuit load. Generic transformers may undervolt under load, causing intermittent lockouts and nuisance tripping on the secondary fuse.
• Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or push-in connectors. Verify secondary output (24V ±10%) with a multimeter before reconnecting the control circuit. Check for any shorted 24V wiring that caused the original failure.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Designed specifically for the Carrier C48A304051 packaged unit. Confirm your existing transformer's VA rating and primary/secondary voltages on your unit's data plate before ordering. If you're unsure of fitment, our HVAC parts specialists are available to verify compatibility before you purchase — same-day shipping on all in-stock orders.