OEM Carrier Furnace Transformer 40VA 120V/24V for Model PG9MAB024040ABSA (Replaces HT01BC116)

This OEM step-down transformer is the factory-specified replacement for the Carrier PG9MAB024040ABSA gas furnace. The transformer is the backbone of the furnace's low-voltage control circuit — it converts 120V line voltage down to 24V AC to power the thermostat, control board, gas valve, and all low-voltage components. When the transformer fails, the furnace goes completely unresponsive: the thermostat loses communication, the inducer never energizes, and no heating cycle can begin. If you're reading 0V between the R and C terminals on your control board, a failed transformer is the first component to test. This listing supplies the current OEM-authorized replacement (supersedes original part number HT01BC116).

• Specs: 40VA rating | 120V primary input | 24V secondary output | 60 Hz single-phase | Foot-mount bracket | Wire lead connections with insulated female quick-connect terminals | Approx. 3"L × 2-3/16"W × 2"H
• OEM vs Generic: OEM transformers are wound to factory-exact VA ratings and insulation class, protecting downstream components like the control board and gas valve. Generic units often run at looser VA tolerances, which can cause nuisance tripping, overheating, and premature failure of the low-voltage circuit.
• Install difficulty: 2/5 — Always shut off power at the breaker and confirm 0V with a multimeter before touching any wiring. Photograph all wire connections before removing the old transformer. Discharge any stored voltage, swap wire leads one at a time to the matching terminals, and secure the foot-mount bracket. Tools needed: flathead and Phillips screwdrivers, 1/4" nut driver, multimeter.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day when ordered by 5 PM local time.

Compatibility: Engineered as a direct OEM replacement for Carrier model PG9MAB024040ABSA gas furnaces. Also supersedes legacy part numbers HT01BC116, HT01BC115, HT01BB126, HT01CT120, HT01BC120, HT01AW115, and HT01AA012. Verify your unit's data plate and confirm 120V primary / 24V secondary / 40VA rating before ordering. Have a fitment question? Our HVAC parts team confirms compatibility before you buy — reach out before you order.