OEM Carrier Furnace Transformer 120V to 24V 40VA — HT01CN001 for Model UPFLOW125FAUAC14B

The Carrier HT01CN001 is the factory-specified control circuit transformer for the UPFLOW125FAUAC14B upflow gas furnace. This transformer steps down 120V line voltage to a 12/24V secondary output at 40VA, powering every low-voltage control circuit in the system — including the thermostat, gas valve solenoid, inducer relay, and ignition board. When this transformer fails, the entire control system goes dark: the thermostat loses power, the furnace refuses to respond to any call for heat or cooling, and you may detect a faint buzzing or burning smell near the control panel. Replacing it with the correct OEM unit restores full factory-specified control circuit performance immediately.

• Specs: 120V primary | 12V/24V dual secondary | 40VA rated | Factory OEM part number HT01CN001 | Replaces legacy part numbers HT01BJ115, 19EA41612, 19EA42612
• OEM vs Generic: This is a genuine Carrier OEM transformer, wound and tested to exact factory VA and voltage tolerances. Off-brand substitutes often run undersized VA ratings, causing nuisance tripping, control board resets, and premature failure of downstream components like gas valve solenoids.
• Install difficulty: 3/5 — Shut off all power to the furnace at the breaker and disconnect switch before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output before reconnecting controls), wire nuts or spade terminals. Always photograph the original wiring harness before disconnecting. Match wire-by-wire on reinstall.
• Warranty: 1-year Carrier OEM factory warranty. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Engineered as a direct OEM replacement for Carrier model UPFLOW125FAUAC14B upflow gas furnaces. Verify your unit's control board voltage requirement (24V) and confirm the existing transformer VA rating on your data plate before ordering. Need fitment assistance? Our HVAC parts specialists verify compatibility before you buy — call or chat today. In stock and ships today.