OEM Carrier Control Transformer 40VA 120V/24V for Model PY3PPA060090AA — Part HT01BD209

This OEM Carrier transformer (part HT01BD209) is the factory-specified control circuit transformer for the Carrier PY3PPA060090AA packaged unit. The transformer steps down 120V line voltage to the 24V AC signal that powers every component in your control circuit — thermostat, contactor coil, gas valve, and control board. When the transformer fails, the entire control circuit goes dark: the thermostat shows no power, and the system will not heat or cool regardless of the call for conditioning.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | Factory OEM part number HT01BD209 | Direct plug-and-play replacement
• OEM vs Generic: OEM transformers from Carrier use the same core material, bobbin, and VA tolerance as the factory-installed unit. Generic substitutes often run near the edge of their VA rating, leading to premature burnout — especially in systems with high-draw accessories like humidifiers or multiple zone controllers.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (to verify 0V before touching terminals), wire stripper, and needle-nose pliers. Label all low-voltage wires before removal and inspect the secondary side for any short-circuit condition that may have caused the original failure.
• Warranty: 1-year OEM factory warranty. Orders placed before 3 PM ship same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for the Carrier PY3PPA060090AA packaged unit. Verify your existing transformer's primary voltage (120V), secondary voltage (24V), and VA rating against the data plate inside your unit's control section before ordering. Our technical team is available to confirm fitment — reach out before you order if you have any questions.