I have a AuqaPower Tankless water heater I installed myself 2 years ago. I used the old wire from old (tank) water heater and I ran a new wire for the 2nd place. It has worked great for 2 years and never an issue, 2 nights ago while cooking I noticed the water was really hot and had to turn it down. About 30 min later my son went to take a bath and no hot water. I checked breaker and it was not tripped- the next day I even changed out the breaker. I tested the 2 lines (before changing breaker) going into the water heater and the new line is getting juice but the old wire is showing none. Does anyone know what could be the problem? I am very handy around the house and I have pretty much remodeled my whole house with the help from my dad- but this has me stumped!!