OEM Carrier Furnace Control Transformer 40VA 120V/24V for Model PG8DAA048095ABJA

This OEM 40VA step-down transformer is the factory-specified replacement for the Carrier PG8DAA048095ABJA gas furnace, replacing discontinued OEM part number HT01BC116 (superseded by HT680054). The transformer converts 120V line voltage down to the 24V AC signal required to power the entire low-voltage control circuit — including the thermostat, gas valve, inducer relay, and ignition board. When this transformer fails, the furnace goes completely dead: no thermostat response, no inducer, no ignition attempt. If you're getting zero 24V at the secondary terminals, this transformer is the first component to test and replace.

• Specs: 40VA rating | Primary: 120 VAC | Secondary: 24 VAC | 50/60 Hz | Single phase | Compact chassis-mount housing (approx. 3" L × 2-3/16" W × 2" H)
• OEM vs Generic: This OEM-spec unit is wound to exact Carrier tolerance, ensuring stable 24V output under full load. Generic transformers often run slightly off-voltage, which can cause intermittent board lockouts, erratic thermostat behavior, and premature contactor coil wear.
• Install difficulty: 2/5 — Shut off power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (to confirm 0V before touching terminals and verify 24V output after). Label all low-voltage wires before disconnecting. Reconnect primary leads first, then secondary. Typical job time: 20–35 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 PG8DAA048095ABJA gas furnace. Supersedes discontinued part HT01BC116. Also replaces cross-reference part numbers HT01BC115, HT01BB126, HT01CT120, HT01BC120, HT01AW115, and HT01AA012 on compatible Carrier, Bryant, and Payne furnace platforms. Always confirm your unit's control board voltage requirement (24V secondary) on the furnace data plate before ordering. Questions about fitment? Our HVAC parts specialists verify compatibility before you buy — reach out before you order.