OEM Carrier 40VA Control Transformer for Model C48A303052

This is the factory OEM replacement transformer (part# HT01BD236) for the Carrier C48A303052 packaged unit. The control transformer steps down line voltage (120V) to the 24V signal required by your thermostat, contactor coils, gas valve, and control board. When the transformer fails, the entire control circuit goes dead — your thermostat will display nothing, the system won't respond to any calls for heating or cooling, and nothing will operate. It is often the first component to inspect when a unit shows zero signs of life.

• Specs: 40VA rated | Primary: 120V | Secondary: 24V | Factory-matched OEM tolerances | Part Number: HT01BD236
• OEM vs Generic: The OEM HT01BD236 transformer is wound and insulated to Carrier's exact specifications, ensuring stable 24V output under full load. Generic transformers frequently sag below 24V when multiple components draw current simultaneously, causing erratic lockouts and nuisance trips.
• Install difficulty: 2/5 — Disconnect power at the disconnect box and verify with a non-contact voltage tester before proceeding. Tools needed: flathead and Phillips screwdrivers, wire nuts or spade connectors, multimeter to confirm 24V output after installation. Always note wire colors and terminal positions before disconnecting the old unit.
• Warranty: 1-year OEM factory warranty. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Designed for the Carrier C48A303052 packaged gas/electric unit. Before ordering, confirm the transformer VA rating and primary/secondary voltages on your unit's data plate match this specification. If your system uses a 75VA transformer, a different part number will apply. Have questions about fitment? Our HVAC parts specialists verify compatibility before your order ships — reach out today.