RELAY

For service buyers searching by part number, 18-1903-28 corresponds to the relay. In service work, this part is selected when troubleshooting points to component failure rather than a wiring, control setting, or maintenance issue. Confirm the equipment brand and the original part reference on the unit before installing a replacement. Where model references are available, cross-check the service model and revision level because similar machines can use different parts. Helps the circuit start and switch loads correctly when the machine is not starting, clicking, or short cycling. When this component fails, technicians may see issues such as compressor not engaging, hard starts, and intermittent operation. Relay or contactor faults can interrupt startup and cycling, especially when contacts are worn or the coil becomes unreliable. For this relay/contactor category, the typical repair goal is to restore the function that the failed component was affecting. Before ordering, technicians usually confirm the part number, inspect adjacent components, and test the affected circuit or mechanism. Relay diagnosis usually includes continuity checks, contact inspection, and verification that the controlled load is not causing arcing or chatter. After installation, technicians typically monitor startup or cycle operation to confirm the machine returns to normal behavior. Once the failed part is confirmed, replacing it with the correct item can restore normal function and prevent ongoing intermittent complaints. Documenting voltage, resistance, temperature, or flow readings during diagnosis also helps validate the repair after installation. Before checkout, verify the part number on the old component and the machine identification tag. Many service calls involve symptoms like not turning on, no power, not cooling, not starting, intermittent operation, error code faults, or ice not dropping, but those complaints can come from multiple causes. Accurate diagnosis plus correct part-number matching is the best way to avoid delays and repeat service visits.