OEM Carrier 75VA Control Transformer HT01BD242 for Model PH1PNB024000AAAA

This OEM Carrier control transformer (part #HT01BD242) is the factory-specified replacement for the Carrier PH1PNB024000AAAA packaged heat pump unit. The transformer steps down the high-voltage supply (208/240/480V primary) to the 24VAC signal required to power the entire low-voltage control circuit — including the thermostat, contactor coil, and safety switch inputs. When the transformer fails, the result is complete loss of control voltage: the thermostat goes blank, the system will not respond to any call for heating or cooling, and no contactors or relays will energize. Replacing a failed transformer is often the fastest, most cost-effective repair on any HVAC system.

• Specs: 75VA power rating | Primary voltage: 208/240/480V | Secondary voltage: 24VAC | Frequency: 50/60Hz | Foot-mount configuration | OEM part #HT01BD242
• OEM vs Generic: This is a genuine Carrier OEM transformer wound to exact factory tolerances. Generic aftermarket transformers often carry ±10% VA tolerance, risking under-voltage conditions that cause nuisance control board lockouts and premature contactor coil failure.
• Install Difficulty: 3/5 — Always shut off and lock out/tag out power at the disconnect before servicing. Tools needed: multimeter (verify 0V before touching wires), flathead and Phillips screwdrivers, wire stripper, and needle-nose pliers. Confirm incoming line voltage matches transformer primary tap before energizing. Recommend verifying 24VAC output after install before closing the unit.
• Warranty: 1-year OEM factory warranty. In-stock units ship the same business day from our warehouse — order by 3 PM local time for same-day dispatch.

Compatibility: Factory-matched for Carrier model PH1PNB024000AAAA packaged heat pump units. The HT01BD242 is also used across a wide range of Carrier, Bryant, Payne, ICP, Heil, Tempstar, and Comfortmaker equipment sharing the same 75VA, multi-tap primary control circuit. Always verify your unit's data plate voltage and VA requirements before ordering. Our parts specialists are available to confirm fitment before you buy.