OEM Carrier 40VA Control Transformer HT01BD702 for Model C48A304064

This OEM replacement transformer (part number HT01BD702) is the factory-specified control circuit transformer for the Carrier C48A304064 packaged unit. The transformer steps down line voltage from 120V to the 24V signal required to power your thermostat, contactor coil, and all low-voltage control components. When this transformer fails — due to a short, overload, or age — the entire control circuit goes dead: the thermostat becomes unresponsive, the contactor won't pull in, and the system won't run in any mode.

• Specs: Primary voltage 120V | Secondary voltage 24V | 40VA rating | OEM part number HT01BD702 | Factory-matched electrical tolerances for reliable low-voltage signal output
• OEM vs Generic: OEM transformers are wound and tested to Carrier's exact VA and voltage output specs. Generic units often underrate their VA capacity, leading to premature failure under normal control loads — especially in systems with electronic air cleaners or zone controllers.
• Install difficulty: 2/5 — Always shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label all wires before disconnecting. Verify the old transformer is the fault source by checking for 24V output before replacement.
• Warranty: 1-year OEM factory warranty against defects. In-stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C48A304064 packaged unit. Confirm your existing transformer's primary/secondary voltage ratings and VA rating on the unit's data plate or wiring diagram before ordering. If you have questions about fitment, our HVAC parts specialists will verify compatibility before you order — guaranteed.