OEM Carrier Control Transformer 50VA 120/208/240V–12/24V for Model YAC1840YAC501K

This OEM Carrier transformer (part # P201-35150) is the factory-specified step-down transformer for the Carrier YAC1840YAC501K HVAC system. Its job is critical: it converts high-voltage line power (120/208/240 VAC) down to the safe 12/24V AC your system's control board, thermostat, and low-voltage accessories need to operate. When this transformer fails, the entire control circuit loses power — symptoms include a completely blank thermostat, a system that won't respond to any commands, or a breaker that trips repeatedly due to a shorted secondary winding.

• Specs: 50VA rating | Primary voltage: 120/208/240 VAC multi-tap | Secondary voltage: 12/24 VAC | 60 Hz | Single phase | CSA listed | Dimensions approx. 3.8" L × 3.1" W × 2.2" H
• OEM vs Generic: OEM transformers are wound to exact factory VA and voltage tolerances, ensuring proper current capacity for your control board. Undersized or off-tolerance generic transformers can overheat, blow fuses repeatedly, or damage sensitive control electronics over time.
• Install difficulty: 3/5 — Always disconnect power at the breaker before servicing. Tools needed: multimeter (verify 24V output after install), flathead and Phillips screwdrivers, wire stripper, and spade connectors. Photograph all wiring connections before removing the old transformer. Confirm primary tap matches your supply voltage.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Factory-matched replacement for Carrier model YAC1840YAC501K. Also sold under the Totaline brand (P201-35150). Verify your unit's supply voltage before selecting the correct primary tap. Need fitment confirmation? Our HVAC parts specialists verify compatibility before you order — ships same day.