OEM Carrier Transformer 40VA 120V to 24V for Model HA1BJX024000ADAA

This OEM control circuit transformer (part# HT01AW229) is the factory-specified replacement for the Carrier HA1BJX024000ADAA air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, and all low-voltage switching circuits. When this component fails, the entire control circuit goes dark — your thermostat goes blank, the system won't respond to any calls for heating or cooling, and nothing works. A failed transformer is often the first suspect when a system appears completely dead with no error codes.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01AW229 | Factory-matched output for stable low-voltage control circuits
• OEM vs Generic: This factory OEM transformer is wound to exact VA and voltage tolerances required by the Carrier control board. Undersized or off-tolerance generic transformers can overload, trip the internal breaker repeatedly, or cause erratic thermostat behavior.
• Install difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Label and photograph all wiring connections before removing the old transformer. Verify 24V output with a multimeter after installation before restoring full system power.
• Warranty: 1-year OEM factory warranty against defects. Orders placed by 3PM local time ship same business day from our climate-controlled parts warehouse.

Compatibility: Designed and tested for the Carrier HA1BJX024000ADAA air handler. Always verify your unit's data plate voltage ratings match before installation. If you're unsure of fitment, our parts specialists can confirm compatibility before you order — no guesswork required. In stock and ready to ship today.