OEM Carrier 40VA Control Transformer for Model P1100049WS

This OEM Carrier transformer (part number P201-35150) is the factory-specified replacement for the P1100049WS unit. The transformer steps down 120V line voltage to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When the transformer fails, the system goes completely silent: the thermostat goes blank, the contactor won't pull in, and no heating or cooling function is possible. If you're reading 0V on the secondary side of your transformer with 120V confirmed on the primary, this is your part.

• Specs: 40VA rated | Primary: 120V AC | Secondary: 24V AC | OEM part number P201-35150 | Factory-matched windings and thermal protection
• OEM vs Generic: This OEM transformer is wound to exact factory VA and voltage specifications. Generic transformers often underperform under load, causing erratic thermostat behavior, nuisance lockouts, and premature contactor coil failure due to voltage sag.
• Install difficulty: 2/5 — Shut off power at the breaker and verify with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade terminals. Photograph all wiring connections before disconnecting. Primary wires carry line voltage — exercise caution.
• Warranty: 1-year OEM factory warranty. In stock and ships same business day from our warehouse.

Compatibility: Designed for Carrier model P1100049WS. Verify primary voltage (120V) and VA rating on your unit's data plate before ordering. If your system runs on 208/240V primary, do not install this unit — confirm your specification before purchase. Our HVAC parts team is available to verify fitment before you order — reach out before checkout if you have any questions.