OEM Carrier Control Transformer 40VA 120V–24V for Model PG8JAA036045ADJA

This OEM control transformer is the factory-specified replacement for the Carrier PG8JAA036045ADJA gas furnace, carrying OEM part number HT01BC116 (superseded by HT680054). The transformer is the heartbeat of your furnace's low-voltage control circuit — it steps 120V line power down to 24V to energize your thermostat, control board, gas valve, and inducer relay. When it fails, the entire furnace goes completely silent: the thermostat goes blank, no relays click, and no ignition sequence begins. If your furnace is totally unresponsive and you've already ruled out a blown fuse, a failed transformer is the most likely culprit.

• Specs: 40VA rating | 120V primary / 24V secondary | Single phase | 50/60 Hz | Step-down design | Compact 3" L × 2-3/16" W × 2" H housing
• OEM vs Generic: OEM transformers are wound to exact VA tolerances, protecting downstream components like your control board from voltage sag under load. Generic units often cut VA capacity margins, which can cause nuisance lockouts or premature board failure.
• Install difficulty: 2/5 — Shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Photograph all wiring connections before disconnecting. Typical install time: 20–30 minutes.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day when ordered by 5 PM local time.

Compatibility: Direct OEM replacement for Carrier model PG8JAA036045ADJA gas furnace. OEM part number HT01BC116 has been superseded by HT680054 — both are covered by this listing. Also fits many Bryant and Payne furnaces sharing this transformer spec. Verify 120V primary and 40VA rating on your unit's data plate before ordering. Our fitment team is available to confirm compatibility before you buy — no guesswork required.