I was called to a home to repair a tankless water heater that was not producing hot water. Upon arrival, I found that the unit was not receiving power. I checked the circuit breaker and found that it had tripped. I reset the breaker and tested the unit again. This time, the unit started producing hot water. I checked the unit for any signs of damage and found that the heating element was not working properly. I replaced the heating element and tested the unit again. This time, the unit was producing hot water. I tested the unit for any leaks and found that there were no leaks. I also checked the pressure relief valve and found that it was working properly. I tested the unit for any other issues and found that it was working properly. I explained to the homeowner the issue with the unit and how I fixed it. The homeowner was satisfied with the work and paid me for the service.