OEM Carrier Furnace Transformer 120V to 24V 40VA — HT01CN001 for Model U19X100U36B

This is the factory OEM replacement transformer (part number HT01CN001) for the Carrier U19X100U36B. The control transformer is the electrical backbone of your HVAC system's low-voltage circuit — it steps down 120V line power to a safe 24V signal that powers your thermostat, contactor coil, control board, and zone valves. When it fails, nothing in your system responds: the thermostat goes dark, the system won't activate on command, and you may hear a faint buzz or hum from the transformer itself. Replacing the transformer is the first diagnostic step when the entire control circuit loses power.

• Specs: 120V primary | 12V/24V dual secondary | 40VA rating | Factory-matched windings and insulation class | Replaces legacy part numbers HT01BJ115, 19EA41612, and 19EA42612
• OEM vs Generic: OEM transformers are wound and insulated to exact Carrier factory tolerances, ensuring the correct VA capacity and secondary voltage stability under load. Undersized or off-tolerance aftermarket units can drop voltage under load, causing nuisance lockouts and premature control board failure.
• Install Difficulty: 3/5 — Requires shutting off power at the disconnect and breaker before any work. Tools needed: multimeter (to confirm 0V before touching), flathead and Phillips screwdrivers, wire stripper, and wire nuts or spade connectors. Always photograph existing wiring before removal. Confirm primary and secondary terminal assignments on the new unit before energizing.
• Warranty: 1-year OEM factory warranty. In-stock units ship same business day from our warehouse — get your system back online fast.

Compatibility: Engineered for the Carrier U19X100U36B. Verify your unit's control voltage and VA requirements on the equipment data plate before ordering. Cross-references include OEM part numbers HT01BJ115, 19EA41612, and 19EA42612. Need help confirming fitment? Our HVAC parts specialists verify compatibility before you order — just reach out.