OEM Carrier Transformer 40VA 120V/24V for Model C50A503561

This is the OEM factory-specified control circuit transformer for the Carrier C50A503561 commercial rooftop unit. The transformer steps down 120V line voltage to 24V AC, powering the control board, thermostat circuit, contactor coils, and all low-voltage safety controls. When this transformer fails, the entire control circuit goes dead — you'll see a blank thermostat, no response to any call for heating or cooling, and often a tripped or blown control fuse. OEM part number HT01BD236 ensures an exact factory fit with no wiring modifications required.

• Specs: 40VA output rating | Primary: 120V AC | Secondary: 24V AC | OEM Part: HT01BD236 | Factory-matched terminal configuration
• OEM vs Generic: OEM transformers are wound to exact VA and voltage tolerances for the C50A503561 control board draw. Undersized or off-tolerance generic transformers can overheat, trip thermal protection, and cause intermittent lockouts — problems that are notoriously difficult to diagnose in the field.
• Install difficulty: 2/5 — Disconnect all power before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter (verify 24V output after install), needle-nose pliers. Always verify primary and secondary wiring orientation matches existing connections before energizing.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Designed for the Carrier C50A503561 commercial packaged rooftop unit. Verify your existing transformer's VA rating and primary/secondary voltage on the unit data plate before ordering. If your control fuse continues to blow after replacement, inspect the low-voltage wiring for shorts before condemning the transformer. Need fitment help? Our HVAC parts specialists confirm compatibility before you order — same-day shipping on all in-stock OEM parts.