OEM Carrier Control Transformer 40VA for Model FB4CNF036L15AEAA

This OEM Carrier transformer (part number HT01CN241) is the factory-specified replacement for the FB4CNF036L15AEAA fan coil air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers every component in your control circuit — thermostat, contactor coil, gas valve, and control board. When the transformer fails, nothing responds: the thermostat goes blank, the system won't call for heating or cooling, and you may measure 0V at the R and C terminals on your control board. A failed transformer is often the first casualty of a shorted zone valve, bad thermostat wiring, or a grounded low-voltage wire.

• Specs: 40VA rating | 120V primary / 24V secondary | Factory-matched impedance | Meets UL and original OEM electrical tolerances
• OEM vs Generic: The OEM HT01CN241 transformer is wound to exact factory VA and impedance specifications. Generic transformers with loose tolerances can under-deliver current under load, causing intermittent lockouts, erratic thermostat behavior, and premature control board failure.
• Install Difficulty: 2/5 — Shut off the air handler disconnect and verify zero voltage at the transformer primary before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, wire stripper. Photograph all wiring connections before disconnecting. Replacement typically takes 20–30 minutes.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed specifically for the Carrier FB4CNF036L15AEAA fan coil air handler. Always verify transformer VA rating and primary/secondary voltages on your unit's data plate before ordering. If you've had a low-voltage short, inspect all 24V wiring for damage before installing the new transformer to prevent repeat failures. Questions about fitment? Our HVAC parts specialists verify compatibility before you order — same-day shipping on in-stock parts.