OEM Carrier 40VA Control Transformer 208/240V to 24V — HT01BD209 for Model PY2PPB048090AB

The Carrier HT01BD209 is the factory-specified 40VA control transformer for the PY2PPB048090AB packaged gas/electric unit. Its job is straightforward but absolutely critical: it steps down the 208/240V line voltage to the 24V signal voltage that powers every low-voltage control in the system — thermostat, contactor coil, gas valve, and control board. When this transformer fails, the entire control circuit goes dead. You'll see a completely unresponsive thermostat, no fan operation, no heating, and no cooling — as if the system has no power at all. A blown secondary fuse on the control board is often the first clue that the transformer has shorted.

• Specs: Input (primary) voltage: 208/240V AC | Output (secondary) voltage: 24V AC | Power rating: 40VA | Frequency: 50/60 Hz | OEM part number: HT01BD209
• OEM vs Generic: This factory OEM transformer is wound to exact Carrier tolerances, ensuring stable 24V output under full VA load. Off-brand substitutes frequently deliver fluctuating secondary voltage that causes nuisance lockouts, erratic thermostat behavior, and premature control board failure.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Photograph all low-voltage wiring connections before removal. Check for the short that burned out the original transformer before energizing the new part.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Direct OEM replacement for Carrier model PY2PPB048090AB packaged units. Verify your unit's data plate shows a 208/240V primary and 24V secondary control circuit before ordering. Not sure it fits? Our HVAC parts specialists confirm fitment before you buy — order with confidence and get back up and running today.