OEM Carrier 40VA Control Transformer HT01BC208 for Model 09DE084C910

This is the factory OEM replacement control transformer for the Carrier 09DE084C910. The transformer steps line voltage (120V) down to the 24V AC signal that powers your entire control circuit — including the thermostat, contactor coil, and control board. When this part fails, the system goes completely unresponsive: the thermostat goes dark, no calls for heating or cooling are processed, and the unit will not run in any mode. It is often the first component to diagnose when nothing else responds.

• Specs: Input 120V AC | Output 24V AC | 40VA rating | Factory-matched OEM tolerances | Direct plug-in or wire-lead termination
• OEM vs Generic: This is the factory-specified OEM transformer (part HT01BC208). OEM units are wound and insulated to Carrier's exact VA and thermal specifications. Generic transformers may be under-rated in VA, leading to overheating, premature failure, or nuisance tripping of the built-in fuse.
• Install difficulty: 2/5 — Shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to confirm 24V output after install). Always photograph existing wiring before disconnecting leads.
• Warranty: 1-year OEM factory warranty against defects. Ships same business day from our warehouse when ordered before 3PM local time.

Compatibility: Designed for Carrier model 09DE084C910. Verify input voltage and VA rating on your unit's data plate before ordering. If your system has a separate 40VA fuse or fusible link on the secondary circuit, inspect it as well — a shorted component downstream may have caused the original transformer failure. Our HVAC parts specialists are available to confirm fitment before you order.