I was called to a customer's home to fix a water heater that was not producing hot water. I found that the water heater was not getting power and was not popping the code. I checked the power supply and found that the power cord was loose. I tightened the power cord and the water heater started working again. I also noticed that there was no pipe coming from the inlet side of the water heater, but the heater was pulling air just fine. The customer wanted to leave the water heater as is, but I recommended flushing it to remove any sediment that may have built up inside. I started flushing the water heater and the customer decided to leave it as is.