OEM Carrier Control Transformer 40VA 120V/24V for Model C48A702564

This is the factory OEM replacement transformer (part number HT01BD702) for the Carrier C48A702564 packaged unit. The transformer steps down line voltage from 120V to the 24V AC signal that powers the entire control circuit — including the thermostat, contactor coil, and control board. When it fails, the result is total control-side shutdown: the thermostat goes dark, nothing responds, and the system won't start at any stage. A failed transformer is often misdiagnosed as a bad control board, making this an essential first check.

• Specs: 40VA rated | Primary: 120V AC | Secondary: 24V AC | Factory-matched to Carrier C48A702564 control circuit requirements | Compact form factor for packaged unit installation
• OEM vs Generic: The OEM HT01BD702 transformer is wound and rated to exact factory specifications, ensuring proper VA capacity and insulation class. Undersized generic transformers can overheat, blow fuses, or cause nuisance lockouts under full control-circuit load.
• Install difficulty: 2/5 — Always disconnect power at the disconnect box before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Verify 24V output at secondary terminals before reconnecting the control circuit. Photograph all wiring before removal.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Designed for the Carrier C48A702564 packaged unit. Verify transformer VA rating and primary/secondary voltage on your unit's data plate before ordering. If your system is blowing the 3A control fuse repeatedly, inspect for shorted wiring before replacing the transformer. Our technical team is available to confirm fitment prior to purchase — order with confidence and receive same-day shipping on in-stock OEM parts.