OEM Carrier 40VA Control Transformer for Model HB1BJX024000AAAA

This OEM control transformer (part number HT01AW229) is the factory-specified replacement for the Carrier HB1BJX024000AAAA air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, contactor coils, and control board. When it fails, the entire control circuit goes dead — the thermostat loses power, the system stops responding to calls for heating or cooling, and nothing works. A blown fuse on the secondary side is often the first clue; if replacing the fuse doesn't hold, the transformer itself is the likely culprit.

• Specs: 40VA rating | 120V primary / 24V secondary | Class 2 control circuit transformer | OEM part number HT01AW229 | Factory-matched impedance and insulation class
• OEM vs Generic: This OEM unit is wound to Carrier's exact VA and voltage tolerance specifications. Generic transformers can run under-rated VA, causing thermal overload under normal HVAC control loads and shortening service life significantly.
• Install difficulty: 2/5 — Shut off power at the disconnect and breaker before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Label or photograph all wiring connections before removing the old transformer. Verify 24V output with a multimeter before closing the panel.
• Warranty: 1-year OEM factory warranty. Orders placed by 3 PM local time ship same business day from our warehouse.

Compatibility: Designed and tested for the Carrier HB1BJX024000AAAA air handler. Confirm your unit's control voltage and VA requirement on the data plate before ordering. If you're unsure of fitment, our HVAC parts specialists verify compatibility before your order ships — no guesswork required.