OEM Carrier Control Transformer 40VA 208/230V–24V for Model PF4MNA037T00ABAA

This is the genuine OEM Carrier control transformer (part #HT01CN241) for the Carrier PF4MNA037T00ABAA fan coil and air handler. The transformer steps down 208/230V line voltage to the 24V signal needed to power your thermostat, control board, and all low-voltage switching circuits. When this transformer fails, your entire control circuit goes dark — the thermostat goes blank, no heating or cooling stages respond, and no safety outputs fire. It is frequently misdiagnosed as a failed thermostat or control board, making accurate diagnosis critical before replacing higher-cost components.

• Specs: 208/230V Primary | 24V Secondary | 40VA rating | Direct-mount OEM form factor | Factory part #HT01CN241
• OEM vs Generic: This OEM unit is wound to exact Carrier factory tolerances, ensuring stable 24V output under full VA load. Generic transformers often run hot under full load and can sag below 24V, causing intermittent lockouts and nuisance tripping of low-voltage fuses.
• Install Difficulty: 2/5 — Always shut off power at the breaker and discharge any capacitors before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter (to verify 24V output after install). Label all low-voltage wires before disconnecting the old unit.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day from our warehouse when ordered before cutoff.

Compatibility: Verified fit for Carrier model PF4MNA037T00ABAA fan coil / air handler. The 40VA rating supports full low-voltage load including multi-stage thermostats and communicating system accessories. Verify your unit's data plate shows a 208/230V primary and 24V secondary requirement before ordering. Our fitment team is available to confirm compatibility before you buy — don't guess on a control circuit part.