OEM Carrier Control Transformer 120V–24V 40VA for Model PH13NR030000AEAA

This is the factory OEM replacement transformer (part number HT01AW229) for the Carrier PH13NR030000AEAA heat pump system. The transformer steps down 120V line voltage to the 24V signal voltage that powers the entire low-voltage control circuit — including the thermostat, contactor coil, reversing valve solenoid, and any connected controls. When the transformer fails, the system goes completely silent: the thermostat goes dark, no call for heating or cooling is recognized, and no contactors or relays can energize. A failed transformer is often mistaken for a full control board failure, making this an important and cost-effective first diagnosis step.

• Specs: Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | Direct OEM replacement for part number HT01AW229 | Factory-matched windings and core for reliable low-voltage output
• OEM vs Generic: The OEM HT01AW229 transformer is wound to Carrier's exact 40VA output specification, ensuring stable 24–28V control voltage under full load. Generic transformers frequently under-deliver VA capacity, causing voltage sag that triggers nuisance lockouts and premature contactor coil failure.
• Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flat-head and Phillips screwdrivers, wire stripper, multimeter (to verify 24V output after install). Photograph all low-voltage wiring prior to disconnection and confirm primary voltage is present at the transformer before condemning the part.
• Warranty: 1-year OEM factory warranty included. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Designed specifically for the Carrier PH13NR030000AEAA heat pump. Verify 120V primary supply and 40VA rating on your unit's wiring diagram or data plate before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before you buy — contact us before ordering.