OEM Carrier Control Transformer 40VA 120V to 24V for Model C48A205052

This is the OEM factory-specified replacement transformer (part number HT01BD236) for the Carrier C48A205052 packaged unit. The transformer steps down line voltage (120V) to the 24V signal used by the thermostat, control board, contactor coil, and all low-voltage control components. When this part fails, the entire control circuit loses power — the system will appear completely dead, with no response from the thermostat, no contactor pull-in, and no ignition sequence. It is often the first component to inspect when nothing works at all.

• Specs: 40VA rating | Primary: 120V | Secondary: 24V | Factory OEM part number HT01BD236 | Engineered to Carrier factory tolerances for the C48A205052
• OEM vs Generic: OEM transformers are wound and insulated to the exact VA rating Carrier specifies. Undersized or off-tolerance generic transformers can overheat, trip their internal breaker repeatedly, or fail prematurely — leaving you with the same no-power symptom within months.
• Install difficulty: 2/5 — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (verify 0V at primary before touching wires). Photograph existing wiring connections before disconnecting. The transformer mounts to the control panel with two screws; primary and secondary leads connect to quick-connect or screw terminals.
• Warranty: 1-year OEM factory warranty against defects. Orders placed before cutoff ship the same business day from our stocked warehouse.

Compatibility: Designed as a direct OEM replacement for the Carrier C48A205052 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate or wiring diagram before ordering. If you have questions about fitment, our HVAC parts specialists confirm compatibility before you buy — no guesswork.