OEM Carrier 40VA Control Transformer 208/230V–24V for Model PF4MNB019L00AAAA

This OEM Carrier transformer (part #HT01CN241) is the factory-specified 24V control circuit transformer for the Carrier PF4MNB019L00AAAA fan coil/air handler unit. The transformer steps down 208/230V line voltage to the 24V AC signal that powers your thermostat, control board, and all low-voltage switching components. When this transformer fails, the entire control circuit goes dead — your thermostat will display nothing, the system will not respond to any call for heating or cooling, and no low-voltage components will operate. It is one of the first components to check whenever the system shows zero response.

• Specs: 208/230V Primary | 24V Secondary | 40VA rating | Direct OEM factory replacement for Carrier part #HT01CN241
• OEM vs Generic: OEM transformers are wound and tested to exact Carrier factory specifications, ensuring stable 24V output under full load. Generic aftermarket units may produce voltage sag or fluctuation that causes nuisance control board lockouts and premature component failure.
• Install Difficulty: 2/5 — Turn off all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Always photograph or label existing low-voltage wiring before disconnecting. The transformer typically mounts inside the air handler cabinet on a bracket with two screws.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day when ordered before cutoff.

Compatibility: Engineered for the Carrier PF4MNB019L00AAAA fan coil/air handler. Verify your existing transformer's primary voltage (208/230V) and VA rating (40VA) against your unit's data plate before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before you order — no guesswork required.