Im having trouble wiring a 240volt water heater for resdential use it is a used like new 82 gallon with 2 elements and was working fine when I got it.The old one was 240volt had a black, a white, and a copper ground wire. The supply wires from the house were the same the old water heater worked but was 30 years old and developed a leak from the tank but it heated water just fine. Now, this one has a black a blue and a yellow and the green screw for the ground.I havent wired it yet because I'm not sure how to. Do I hookup 2 wires to the black supply? I don't have paperwork as it is used.No source online seems to want to offer wiring details, they seem to be vague in the wiring dept. I figure the black and blue from the water heater go to the black power supply and the yellow to the white supply..Can you tell me if I'm on the right track? Thanks, clwcommander45
I fixed the problem or I should say figured it out. My original solution was right on. The black and Blue from the water heater both connect to the Black supply and the yellow from the water heater connects to the White supply. A solid copper ground wire connects to the green screw in the water heater. It works perfect but not at first. The thing I always thought about used water heaters remains the same, they were removed for some reason and like car batteries it's almost always a waste of time to not just go with a new one! So, even though this one worked when it was replaced by an instant system by Bosch I was eventually told this one had an intermittant problem of producing only warm water. Needless to say I only got warm water at first. Tests told me I had 118 volts to both sides of the elements which are rated 4500watts for the top and bottom element. I then measured resistance after disconnecting power first then removing connectons to the elements which has to be done or the test is false. The bottom element was .013 and the top one was .000 . No resistance means no heat. I tested the old waterheaters elements and they both read .013. They wee also rated at 4500 watts so I iinstalled the old top element in the installed new\used water heater and got 82 gallons of 140 degree water in a couple of hours. I had to modify the mount bracket for the element , that was simple and no money had to be spent. As nice condition the old elements are in I kept the bottom one and stripped the old one of thermostats and wires etc.
