OEM Carrier Control Transformer 40VA 120V/24V for Model PF1MNC018005AAAA

This OEM Carrier control transformer (part number HT01CN241) is the factory-specified replacement for the Carrier PF1MNC018005AAAA fan coil unit. The transformer steps down the 120V line voltage to the 24V AC signal required to power the entire low-voltage control circuit — including the thermostat, control board, and relay coils. When this transformer fails, nothing in the system responds: the thermostat goes dark, the contactor won't pull in, and the unit is completely inoperable. A blown fuse on the secondary side of this transformer is often the first diagnostic clue of its failure.

• Specs: 40VA rating | 120V primary | 24V secondary | Factory-matched OEM construction | Plug-and-play terminal connections
• OEM vs Generic: This is a genuine Carrier OEM transformer. Generic substitutes often use undersized VA ratings or inferior core laminations, leading to thermal overloads and repeated control circuit failures.
• Install difficulty: 2/5 — Shut off all power at the disconnect and breaker before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire labels. Always verify 0V at the primary terminals before touching wiring.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: This transformer is the direct OEM replacement for Carrier PF1MNC018005AAAA fan coil units. Verify your existing transformer's primary voltage, secondary voltage, and VA rating on the data plate before ordering. Need help confirming fitment? Our HVAC parts specialists are standing by to verify compatibility before you order — reach out before placing your order.