How to Repair a Doorbell in 11 Steps


Check the Transformer Power

Before replacing transformer, check to make sure it's getting power from the 110-120-volt circuit. With circuit deenergized, disconnect transformer from line wires. Then turn circuit back on again and touch probes of 110-120-volt circuit tester to bare wire ends. If tester light glows or indicator reads 110-120 volts, circuit is okay.