OEM Carrier 24V Control Transformer 40VA for Model PF4MNB043L00ACAA

This OEM replacement control transformer (part # HT01CN241) is the factory-specified unit for Carrier PF4MNB043L00ACAA air handlers. The transformer steps line voltage (120V) down to 24V AC to power the low-voltage control circuit — including the thermostat, contactor coils, and control board. When it fails, the entire control circuit goes dead: the thermostat loses power, nothing responds, and the system won't start at all. Replacing the transformer is one of the most cost-effective repairs in HVAC service.

• Specs: Input 120V AC | Output 24V AC | 40VA rated | Factory-matched OEM construction | Class 2 transformer
• OEM vs Generic: This OEM unit (HT01CN241) is wound to Carrier's exact VA rating and insulation class. Generic transformers often undersell their VA rating, causing overheating and premature failure — especially when multiple zone valves or relays are on the circuit.
• Install Difficulty: 2/5 — Straightforward swap requiring only a screwdriver and multimeter. Always shut off power at the disconnect and breaker before working. Verify 24V output with a multimeter before buttoning up the unit. Photo-document all wiring connections prior to removal.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before 3 PM local time.

Compatibility: Designed as the direct OEM replacement for Carrier PF4MNB043L00ACAA air handler units. Always confirm primary voltage and VA rating on your unit's data plate before ordering. Need help verifying fitment? Our HVAC parts specialists confirm compatibility before your order ships.