OEM Carrier 40VA Control Transformer 120V–24V for Model PG9MAA048080ACKA

This OEM control transformer is the factory-specified replacement for the Carrier PG9MAA048080ACKA gas furnace, cross-referencing original part number HT01BC116 (superseded by HT680054). The transformer steps down line voltage from 120V primary to a 24V secondary signal that powers the entire low-voltage control circuit — including your thermostat, gas valve, inducer relay, and control board. When this transformer fails, the furnace goes completely dark: the thermostat shows no power, the board won't sequence, and you get zero heat output. If you're reading 0V on the secondary side of your transformer with confirmed 120V on the primary, this is your part.

• Specs: 40VA rating | 120V primary | 24V secondary | 50/60 Hz | Single phase | Wire lead connection type | Compact 3" L × 2-2/16" W × 2" H form factor
• OEM vs Generic: This is a genuine OEM-equivalent Carrier replacement, manufactured to exact VA and impedance tolerances. Generic aftermarket transformers frequently run under-rated VA, causing voltage sag under load and premature control board failure — a costly second repair.
• Install difficulty: 2/5 — Shut off the furnace disconnect and confirm zero voltage before touching any wiring. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wire connections before removal. Discharge time is not a concern with transformers (unlike capacitors), but always verify power is off.
• Warranty & Shipping: 1-year OEM manufacturer warranty. In stock and ships same business day when ordered by 5 PM local time. Replaces legacy part numbers HT01BC116, HT01BC115, HT01BB126, HT01CT120, HT01BC120, and several additional superseded Carrier part numbers.

Compatibility: Engineered for Carrier PG9MAA048080ACKA gas furnaces and confirmed to fit a broad range of Carrier, Bryant, and Payne furnace models requiring a 40VA / 120V–24V step-down control transformer. Verify your original part number on the unit's data plate or wiring diagram before ordering. Our parts specialists are available to confirm fitment — reach us before you order and we'll make sure you get the right part the first time.