OEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C50AK04161

This OEM control transformer (part number HT01BD236) is the factory-specified replacement for the Carrier C4850C50AK04161 packaged unit. The transformer steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, contactor coil, and all safety circuits. When this component fails, the entire control circuit goes dead — the thermostat goes blank, the system stops responding to calls for heating or cooling, and no sequencing can occur. A failed transformer is often misdiagnosed as a board or thermostat failure, making correct identification critical before replacing costlier components.

• Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01BD236 | Designed to factory tolerance for Carrier packaged equipment
• OEM vs Generic: This OEM transformer is wound and insulated to Carrier's exact specifications, ensuring stable 24V output under full load. Generic alternatives frequently deliver fluctuating voltage that causes nuisance lockouts, contactor chatter, and premature control board failure.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify zero voltage with a multimeter before proceeding. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label or photograph all low-voltage wiring connections (R, C, G, Y, W) before disconnecting the old transformer.
• Warranty: 1-year OEM factory warranty against defects. In-stock units ship same business day from our warehouse when ordered before 3 PM local time.

Compatibility: Direct OEM replacement for Carrier model C4850C50AK04161 packaged unit. Verify your existing transformer's VA rating and primary/secondary voltages on the unit's data plate or wiring diagram before ordering. If you're unsure of fitment, our HVAC parts specialists confirm compatibility before your order is placed — no guesswork required.