OEM Carrier 40VA Control Transformer HT01BD242 for Model PH3ZPA060000AA

This OEM step-down control transformer is the factory-specified replacement for the Carrier PH3ZPA060000AA packaged unit. The transformer steps down 120V line voltage to the 24V signal required by the thermostat, control board, and all low-voltage components in the system. When it fails, the entire control circuit goes dead — the thermostat becomes unresponsive, the system will not heat or cool, and no fault codes will display because the board itself has no power.

• Specs: 40VA rating | Primary: 120V | Secondary: 24V | OEM part number HT01BD242 | Factory-matched impedance and thermal protection
• OEM vs Generic: This OEM transformer is wound to Carrier's exact VA rating and insulation class, ensuring proper current capacity for the full low-voltage load. Generic transformers rated at lower VA can overheat, trip internal breakers, or fail prematurely under full board load.
• Install Difficulty: 2/5 — Shut off all power at the disconnect before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter (to verify 24V output after install). Photograph or label all wire connections before removing the old unit. Always confirm VA rating on the old unit's label before ordering.
• Warranty: 1-year OEM factory warranty. In-stock units ship same business day from our warehouse.

Compatibility: Designed for the Carrier PH3ZPA060000AA packaged unit. Confirm the 40VA / 120V primary / 24V secondary rating on your unit's data plate or existing transformer label before ordering. Need help verifying fitment? Our HVAC parts specialists confirm compatibility before you purchase — no guesswork required.