OEM Carrier Transformer 40VA 120V–24V for Model FX4DNB037L00ACAA

This is the factory OEM replacement transformer (part# HT01CN241) for the Carrier FX4DNB037L00ACAA fan coil air handler. The transformer steps down line voltage from 120V to 24V AC to power the low-voltage control circuit — including the thermostat, control board, and all safety switching. When this component fails, nothing in the system responds: the thermostat goes dark, the blower won't engage, and no call for heat or cool is processed. A failed transformer is often misdiagnosed as a bad control board, making this an important first diagnostic step.

• Specs: 40VA rating | 120V primary / 24V secondary | Class 2 transformer | Direct OEM replacement for part number HT01CN241 | Matched to factory electrical specifications
• OEM vs Generic: The OEM HT01CN241 transformer is wound and insulated to Carrier's exact VA rating and thermal protection standards. Off-brand substitutes frequently under-deliver on VA capacity, causing nuisance tripping, overheating, or premature failure of the connected control board.
• Install difficulty: 2/5 — Disconnect power at the breaker and verify voltage is absent with a multimeter before starting. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Label or photograph all wiring before disconnecting. A 5A control-circuit fuse is common on this platform — check and replace if blown alongside the transformer.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier FX4DNB037L00ACAA fan coil air handler. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering. If you're unsure of fitment, our HVAC parts specialists can confirm compatibility before you buy — same-day shipping on all in-stock orders.