OEM Carrier 40VA Control Transformer HT01CN236 for Model FA4ANC018008AGAA

This is the OEM factory-specified control circuit transformer (part number HT01CN236) for the Carrier FA4ANC018008AGAA fan coil air handler. The transformer steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, and all low-voltage switching circuits. When it fails, absolutely nothing works — the thermostat goes blank, no heating or cooling stages respond, and the system appears completely dead. A failed transformer is one of the most commonly misdiagnosed HVAC faults; always verify 24V output across the secondary terminals with a multimeter before replacing more expensive components like the control board.

• Specs: 40VA rated | 120V primary input | 24V secondary output | OEM part number HT01CN236 | Factory-matched to Carrier FA4ANC018008AGAA control circuit requirements
• OEM vs Generic: OEM transformers are wound to exact VA capacity and insulation class for your unit. Undersized or off-spec generic units can overheat, trip thermal fuses, and damage downstream control boards — making the OEM part a sound investment on a low-cost component.
• Install difficulty: 2/5 — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter, wire nuts or quick-connect terminals. Label all low-voltage wires (R, C, G, Y, W) before disconnecting the old unit. Confirm 24V output on secondary before reassembling the cabinet.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before 3 PM local time.

Compatibility: Designed and factory-spec'd for the Carrier FA4ANC018008AGAA fan coil air handler. Verify your existing transformer's VA rating and primary/secondary voltages on the unit data plate before ordering. If you are unsure of fitment, our HVAC parts specialists are available to confirm compatibility before you purchase — just reach out with your full model and serial number.