OEM Carrier 40VA Control Transformer for Model GB3AAV048095AEJA

This is the OEM factory-specified control transformer (part# HT01BC116) for the Carrier GB3AAV048095AEJA gas furnace. The transformer is the heartbeat of the low-voltage control circuit — it steps down 120V line voltage to the 24V signal voltage that powers your thermostat, gas valve, inducer relay, and control board. When this transformer fails, absolutely nothing in the control system responds: the thermostat goes blank, the furnace locks out entirely, and no components receive a call-to-heat signal. It is one of the first components to test when a furnace shows zero response.

• Specs: 40VA rated | 120V primary / 24V secondary | Class 2 transformer | Direct OEM replacement for part number HT01BC116 | Compatible with R-410A and standard low-voltage thermostat wiring
• OEM vs Generic: OEM transformers are wound and insulated to Carrier's exact VA and impedance specifications. Undersized or off-spec generic transformers can sag under load, cause nuisance board lockouts, or fail prematurely — especially in multi-stage systems drawing full 24V amperage.
• Install Difficulty: 2/5 — Disconnect power at the breaker and confirm zero voltage before proceeding. Tools needed: flathead and Phillips screwdrivers, multimeter (verify 24V output after install), wire nuts or spade connectors. Photograph existing wiring before removal. A failed transformer can sometimes indicate a downstream short — test for shorts on the 24V circuit before installing the new unit.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed as the direct OEM replacement for the Carrier GB3AAV048095AEJA 80% AFUE gas furnace. Always verify your existing transformer's VA rating and input/output voltages on the unit data plate before ordering. Our HVAC parts specialists are available to confirm fitment — reach out before you order if you have any questions. Order now and receive same-day shipping on in-stock parts.