OEM Carrier Transformer 40VA 120V to 24V for Model HA1CJX036000ABAA

This is the factory OEM replacement transformer (part number HT01AW229) for the Carrier HA1CJX036000ABAA unit. The transformer steps down 120V line voltage to the 24V signal voltage required by your thermostat, control board, and all low-voltage control components. When this transformer fails, the entire control circuit goes dead — your thermostat will show no power, the system won't respond to any calls for heating or cooling, and diagnostic LEDs on the control board will be dark. It is often the first component to inspect when the system appears completely unresponsive despite confirmed line voltage at the unit.

• Specs: Primary voltage: 120VAC | Secondary voltage: 24VAC | VA rating: 40VA | OEM part number: HT01AW229 | Factory-matched fit and performance
• OEM vs Generic: This OEM transformer is wound to Carrier's exact VA and impedance specifications. Undersized or off-tolerance generic transformers can overheat, trip on thermal protection, or deliver unstable 24V that causes nuisance lockouts and control board damage over time.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify zero voltage with a multimeter before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Label or photograph all low-voltage wiring connections before removing the old transformer.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for Carrier model HA1CJX036000ABAA. Always verify your existing transformer's primary and secondary voltage ratings and VA rating on the unit data plate or wiring diagram before ordering. Our fitment team is available to confirm compatibility before you purchase — same-day shipping on all in-stock orders.