Electrical 101: Wiring a Hot Water Heater

Homeowners are often faced with the challenge of replacing their hot water heater at some point during their homeownership. This project is relatively simple and once you have the plumbing installed the next step is to wire the hot water heater to the main circuit breaker. While in many cases a homeowner will call an electrician to wire the water heater this is unnecessary due to the ease in wiring a new water heater once there is already the main power source ran and installed. If you have just replaced a water heater in the home and already have the existing wiring from the circuit breaker to the water heater then all you have to do is follow some basic electrical points to wire up the new hot water heater in just a few minutes.

Electrical 101: Wiring a Hot Water Heater Materials

Wire Stripper

Wire Nuts

Electrical Tape

Electrical Tips for Wiring a Water Heater Step 1: Begin by assuring that the main power is shut off to the water heater. Turn the breaker that the water heater is on off! Never begin any electrical job without first turning the main power source off.

Electrical Tips for Wiring a Water Heater Step 2: Once power is turned off, begin by checking the wires coming out of the new water heater. There should be a red wire, a black wire, and a green wire. Make sure at least 1 inch or the main wire for each of these is visible. You can strip the protective plastic using wire strippers.

Electrical Tips for Wiring a Water Heater Step 3: Now, find the existing wiring from the wall where the water heater is in place and assess the wires from there. There will usually be a black wire, a red or white wire and a green wire or a plain wire coming from the main junction box at the circuit breaker panel.

Electrical Tips for Wiring a Water Heater Step 4: Begin by using a wire nut to connect the black wire from the water heater junction box to the black wire from the circuit breaker junction box. Twist the wires together and then place a wire nut over them to hold them securely together.

Electrical Tips for Wiring a Water Heater Step 5: Now, connect the red wire from the water heater to the red or the white wire from the junction box at the circuit panel. Use a wire nut the same as you did in step 4.

Electrical Tips for Wiring a Water Heater Step 6: The green or stripped wire is the ground. From the circuit junction box there will be a grounding distribution terminal that the green wire is connected to. You will connect the green wire from the hot water heater to the grounding terminal as well. This assures that the electrical current is grounded out and will not create a shock hazard. NEVER EVER FORGET TO GROUND THE POWER!

This completes the water heater wiring. You can use electrical tape to tape up the connections of the red and black wires but a wiring nut usually does the trick. Turn on main power and listen for the water heater elements to kick on and begin to heat the water.