OEM Carrier 3-Pole Contactor 208-240V 40A for Model ROA0300L2D

This OEM contactor (part number HN53CD209) is the factory-specified replacement for the Carrier ROA0300L2D commercial condensing unit. The contactor acts as the high-voltage switching relay that energizes the compressor and condenser fan motors each time the thermostat calls for cooling. When the low-voltage control circuit closes the contactor coil, the main contacts snap shut and deliver line voltage to the condensing section. A failed contactor will leave your system dead on a call for cooling, chattering loudly, or — in the case of welded contacts — running non-stop even after the thermostat is satisfied.

• Specs: 3-Pole | 208-240V coil | 40 FLA / 50A RES | Definite-purpose design | Factory-matched contact gap and spring tension for reliable pull-in
• OEM vs Generic: OEM contactors are built to Carrier's exact coil impedance and contact material specs. Generic substitutes often use lower-grade silver-alloy contacts that arc and pit faster, leading to premature welding and compressor damage.
• Install difficulty: 3/5 — Always shut off the disconnect and verify zero voltage with a multimeter before touching any terminals. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wiring connections before disconnecting. Transfer wires one at a time to avoid miswiring.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered for the Carrier ROA0300L2D commercial rooftop/condensing unit. Verify coil voltage (208-240V) on your unit's wiring diagram or data plate before ordering — do not substitute a 24V coil version. Our fitment team is standing by to confirm compatibility before you order. Order today and ship today.