OEM Carrier 40VA Control Transformer HT01BC117 for Model PG9YAB048080AAAA

This is the genuine OEM replacement control transformer for the Carrier PG9YAB048080AAAA gas furnace. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, gas valve, and all low-voltage control circuitry. When this part fails, nothing in the system responds — the thermostat goes blank, the furnace won't fire, and no error codes are displayed because the board itself has no power. A failed transformer is often misdiagnosed as a bad control board, making it one of the most important parts to verify first.

• Specs: 120V primary | 24V secondary | 40VA rated | Direct OEM replacement for part number HT01BC117 | Factory-matched output for Carrier low-voltage control circuits
• OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances required by the Carrier control board. Undersized or off-tolerance generics can cause nuisance tripping of the transformer's internal thermal fuse, intermittent faults, and premature control board damage.
• Install Difficulty: 2/5 — Shut off all power at the breaker and disconnect switch before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Verify 24V output at secondary terminals before reconnecting control wiring. Always photograph existing wiring before removal.
• Warranty: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse.

Compatibility: Engineered specifically for the Carrier PG9YAB048080AAAA packaged gas furnace. Cross-reference your existing part number (HT01BC117) and confirm 120V/24V/40VA ratings on the data plate before ordering. Have questions about fitment? Our HVAC parts specialists verify compatibility before you buy — contact us before placing your order.