OEM Carrier Control Transformer 40VA 120V/24V for Model C48A504061 — HT01BD236

This is the factory OEM replacement control transformer (part number HT01BD236) for the Carrier C48A504061 packaged unit. The transformer steps down line voltage from 120V to the 24V AC signal required by your thermostat, control board, contactor coil, and all low-voltage control circuit components. When this transformer fails, the entire control circuit loses power — the thermostat goes blank, the system will not respond to any calls for heating or cooling, and no safety circuits can operate. It is often one of the first components to check when nothing works at all.

• Specs: 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched to Carrier C48A504061 control circuit requirements
• OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage specifications, ensuring stable 24V output under full load. Generic replacements can sag under load, causing erratic thermostat behavior, nuisance lockouts, and premature contactor coil failure.
• Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter to verify 24V output post-install. Photograph all wiring connections before disconnecting the old unit. Two primary and two secondary leads — note polarity of secondary wiring relative to your control board's C and R terminals.
• Warranty: 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our stocked warehouse.

Compatibility: Designed as the direct OEM replacement transformer for the Carrier C48A504061 packaged unit. Always verify your existing transformer's VA rating and primary/secondary voltages from the data plate or wiring diagram before ordering. If you have any questions about fitment, our HVAC parts specialists confirm compatibility before your order ships — same business day.