OEM Carrier Control Transformer 40VA 208/240V to 24V for Model PY1PPB042060AAAA

This genuine OEM Carrier control transformer (part #HT01BD209) is the factory-specified replacement for the Carrier PY1PPB042060AAAA packaged unit. The transformer steps down 208/240V line voltage to the 24V signal required by your thermostat, control board, contactor coil, and all low-voltage safety circuits. When this part fails, the entire control circuit goes dark — the thermostat shows no response, the system will not call for heating or cooling, and no fault codes are generated because the board itself has no power. A failed transformer is often misdiagnosed as a thermostat or control board failure, making correct identification critical before replacing expensive components.

• Specs: 40VA rating | 208/240V primary | 24V secondary | 50/60Hz | ~1.32 lbs | Cross-references: HT01BD207, HT01CN232, 9076-00
• OEM vs Generic: This is a genuine Carrier OEM transformer wound to exact VA and voltage tolerances. Generic transformers can sag under full load (relays, board, and thermostat drawing simultaneously), causing nuisance lockouts and control board damage over time.
• Install difficulty: 2/5 — Shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label all wire connections before removing the old transformer. Confirm 24V output at secondary terminals before buttoning up the panel.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Direct OEM fit for the Carrier PY1PPB042060AAAA packaged unit. Also replaces superseded part numbers HT01BD207, HT01CN232, and 9076-00. Always verify your unit's data plate voltage against the transformer primary rating (208/240V) before ordering. Have a question about fitment? Our HVAC parts specialists will verify compatibility before you buy — contact us today and get your system back online fast.