OEM Carrier 40VA Control Transformer for Model YAC48140YAC203T

This OEM control transformer (part number P201-35150) is the factory-specified replacement for the Carrier YAC48140YAC203T packaged unit. The transformer steps down line voltage (120V) to the 24V signal voltage required to power the thermostat, control board, and all low-voltage safety and switching circuits throughout the unit. When this transformer fails, the entire control circuit goes dead — the thermostat loses power, contactors won't pull in, and the system will not respond to any call for heating or cooling. A failed transformer is often misdiagnosed as a bad control board, making correct identification of this part critical before replacing more expensive components.

• Specs: Input: 120V AC | Output: 24V AC | Rating: 40VA | OEM Part Number: P201-35150 | Factory-matched to Carrier YAC48140YAC203T electrical specifications
• OEM vs Generic: This OEM transformer is wound and potted to exact factory VA and voltage tolerances. Undersized or off-spec generic transformers can overheat, blow fuses repeatedly, and damage sensitive control boards — costing far more than the price difference.
• Install difficulty: 2/5 — Always disconnect power at the disconnect box and verify zero voltage with a multimeter before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter, and wire nuts. Label and photograph all low-voltage wiring before removing the old unit.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier YAC48140YAC203T packaged unit. Confirm input voltage and VA rating on your unit's data plate before ordering. If you need help verifying fitment, our HVAC parts specialists are available to confirm compatibility before you buy — no guesswork required.