OEM Carrier 40VA Control Transformer 208/240V to 24V — Model PY3GNA060115AB

The Carrier HT01BD209 is the factory-specified 40VA control transformer for the PY3GNA060115AB gas furnace. Its job is to step down the 208/240V line voltage to the 24V low-voltage signal that powers your thermostat, control board, gas valve, and every other control-circuit component. When this transformer fails, the entire low-voltage control circuit goes dead — the thermostat goes blank, the furnace won't respond to any call for heat or cooling, and a multimeter at the secondary terminals will read 0V instead of the expected 24V.

• Specs: Input: 208/240V | Output: 24V secondary | Rating: 40VA | Frequency: 50/60 Hz | OEM Part #: HT01BD209
• OEM vs Generic: This is the genuine Carrier OEM transformer, wound to exact factory VA and voltage tolerances. Generic transformers may run undervoltage under load, causing erratic board behavior, nuisance lockouts, and premature contactor wear.
• Install Difficulty: 2/5 — Shut off power at the disconnect and breaker before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label and photograph all wire connections before removal. Secondary wires are typically color-coded; verify against your wiring diagram.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Direct factory replacement for Carrier model PY3GNA060115AB gas furnace. Also cross-references HT01CN232 and HT01CN233 on select Carrier, Bryant, and Payne units — always verify input voltage, output voltage, and VA rating against your unit's data plate before ordering. Need fitment help? Our HVAC parts specialists confirm compatibility before you buy.