OEM Carrier 40VA Control Transformer HT01BD702 for Model C50A904064

This OEM control transformer (part# HT01BD702) is the factory-specified replacement for the Carrier C50A904064 commercial packaged unit. The transformer steps down 120V primary voltage to the 24V secondary signal that powers your thermostat, control board, and all low-voltage control circuits. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any calls for heating or cooling, and nothing works. It's one of the first components to check when a unit has zero control response.

• Specs: 40VA rated | 120V primary / 24V secondary | Factory-matched OEM design | Built-in thermal overload protection on most configurations — verify your unit's data plate before ordering
• OEM vs Generic: This is a genuine OEM Carrier transformer engineered to the exact VA rating and winding specification required by the C50A904064 control board. Undersized or off-spec generic transformers can fail quickly under full load, causing nuisance lockouts and potential control board damage.
• Install difficulty: 2/5 — Always shut off power at the disconnect and verify voltage is absent before handling. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label or photograph existing wiring connections before disconnecting the old unit.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our stocked warehouse.

Compatibility: Designed for the Carrier C50A904064 commercial rooftop/packaged unit. Confirm primary voltage (120V) and VA rating on your existing transformer's label before ordering to ensure proper fitment. Our HVAC parts specialists are available to verify compatibility before you buy — order with confidence and get your system back online fast.