OEM Carrier Control Transformer 40VA 120V to 24V for Model C48A202051

This is the factory-specified OEM replacement transformer (part number HT01BD236) for the Carrier C48A202051 packaged unit. The transformer steps down line voltage (120V) to the 24V AC signal that powers your thermostat, control board, contactor coil, and every other low-voltage component in the system. When this part fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any command, and no components will energize. A failed transformer is often misdiagnosed as a bad control board, so always verify 24V output at the transformer secondary before replacing more expensive parts.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | Factory-matched output tolerance | Designed for Carrier packaged unit applications
• OEM vs Generic: OEM transformers like this HT01BD236 are wound to exact factory VA and voltage specifications. Undersized or off-tolerance generic transformers can brownout the control circuit under load, causing erratic lockouts and premature contactor coil failure.
• Install Difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or terminal connectors. Confirm 0V at primary terminals before touching any wiring. Label all wires prior to disconnection.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier C48A202051 packaged unit. Cross-reference part number HT01BD236 against your unit's data plate and wiring diagram before ordering. If you're unsure of fitment, our HVAC parts specialists are available to verify compatibility before you purchase — no guesswork required.