Save Money with a Timer on your Water Heater

If you're like most of us (in these lean economic times), you're looking at all your options to save a few dollars on recurring bills, like heating and electric. One of the easiest ways to save, if you have an electric water heater in your home, is to install a timer so that you're not heating water at a time when it's not being used. For instance, people who work during daylight hours don't need 40 gallons of hot water at their disposal while they're at work, right? With a timer installed between the power supply and the water heater, you can reduce your energy costs significantly.
But before you grab your screwdriver and a pair of rusty pliers and head off to the basement to install your timer, let me say this: if you don't have any clue about how electricity works, or safe procedures while working with electricity, then HIRE A PRO. This isn't a job for the average guy who hasn't done electrical work before. If you have any doubt about your budding electrician skills, call a contractor to install your timer. Even if you pay a hefty price for the installation, you'll still come out WAY ahead in the utility bill department when it's done. Better safe than deep-fried . Besides, you'd look pretty damn stupid if you were found in your basement with your shoes melted to the wall and smoke coming out your ears. Play it safe.
Most electric water heaters are serviced by a 220V circuit, rather than 110V like a lighting circuit. There are a few 110V water heaters out there, but they're actually less energy efficient than the 220V variety. An easy way to tell, if you're not familiar with "things electrical", is to look at the breakers in the distribution box.. A 110 circuit will have ONE wire attached to the breaker (usually, but not always, the black wire), and ONE wire connected to the buss bar on the side, back or bottom of the distribution box. This wire is (usually) white. The bare (ground) wire will be connected to the buss bar as well. When the ground wire and neutral (white) wire are both connected to the buss bar, this is known as a "bonded" panel. If the breaker has TWO wires connected to it, and the breaker is roughly twice as wide as the breakers that are fed by ONE wire, then it's most likely a 220 circuit. You'll need to make sure you purchase a timer that's rated for 220V. The wiring used for a water heater is normally 10/2 or 12/2 Romex wire, made of copper with a plastic insulation sleeve.
Timers vary greatly as far as features, but all of them do basically the same thing: they cut off the power to the water heater during times when hot water isn't needed, and turn the power back on when it IS needed. Pricing at most home stores runs between $90 and $150, but you'll save at least that much in a year. Make sure the timer has at least 2 on/off cycles per day to maximize your energy savings.
Start by turning off the breaker for the water heater, and be sure to ascertain that the circuit is dead before proceeding. You can use a simple current tester to do this.
Next, the wiring will need to be disconnected from the water heater. Most have an access panel in the top or side that you'll need to remove, and inside you'll (usually) find that a pigtail ( a length of wire) has been run from the interior panel of the water heater to the area you've just accessed. Remove the wire nuts to disconnect the wiring.
The wire that you've just disconnected will now be connected to the timer. You can locate your timer in the basement, or in a place more convenient for programming like a bathroom wall or storage area. Be sure to mount the timer high enough to prevent tampering by children or rogue pets. Plan the routing of your wiring so that it's an easy run, without drilling through too many floor joists or walls, between the distribution box and the timer.
Mount the timer securely and run the wiring inside the wall or closet to your timer. Mark the wire using an indelible marker as FROM BREAKER. If it isn't long enough for the run, you'll need to disconnect it at the breaker and run a longer piece of wiring. If that is the case, be sure to turn off the MAIN breaker on your distribution panel before proceeding. Reaching into a live distribution box can get ugly. If you decide to wire it without shutting off the main, then do your spouse a favor and make sure your life insurance policy is paid-up. I'm not shittin'....most homes today are 200 AMP service and it'll toast you in a heartbeat if you fug up.
Pull the wire up through the timer panel, leaving about 6 inches extra for play. Secure the wiring to the wall studs and floor joists with the proper size staples so that it isn't hanging down or looping into the closet space.
Next, you'll need to run another wire back to the water heater. Start at the timer, leaving 6 inches of extra wire pulled into the timer box body, and route your wire (10/2 or 12/2) back to the water heater. Again, mark the wire....write TO WATER HEATER on it a few feet back from the timer. Make sure to secure it with staples to prevent snagging. Leave a few inches of play in the wire between the last staple and the water heater connection, in case the water heater is replaced in the future and the wire needs to be shortened a little. Strip the wiring insulation back sufficiently to facilitate the connection, cut the insulation away, and strip the individual wires back about 3/8 inch with a utility knife or wire stripper tool. In most cases, you'll be connecting the wires black to red, and white to white, with the bare ground wires being secured under the GREEN screw. Use the wire nuts (the cone-shaped plastic connectors) to twist the wires together, clockwise, and wrap them with a layer of electrical tape as a precaution. Be sure to use the Romex connector to prevent abrasion and stretching on the wire....this is the bracket-like apparatus that fits into the access hole and tightens against the Romex wire.
Ready to wire up the timer? Again, if you have a reasonable idea of how electrical current travels, you can do all this yourself. If you have any doubts, GET A PROFESSIONAL! I can't stress this enough. Your pride might be bruised, and you'll never get into the Tim Taylor Club. Big frickin deal....you'll be alive and unscorched.
At the timer, you're basically making a "junction box"....by that I mean connecting the hot (black) wires to hot wires, neutral (white) to neutral wires, and the bare ground wires will connect once again at the green screw. The only difference is that you'll be connecting each wire to an individual terminal screw, instead of twisting them together with a wire nut. The current will flow in from the open breaker to the timer,and be directed to the water heater only if the timer directs it there by the settings you've programmed into it.
Using the same process you used for the water heater connection, strip the sheathing, then strip the insulation from the individual wires about 3/8 inch. LEAVE A LITTLE EXTRA LENGTH TO THE WIRE...you can always strip the sheathing and insulation back further, but if you strip too far or cut the wires too short, you'll end up replacing the entire length of wire back to the breaker or water heater.
Most timers are configured so that the hot (black wires) each connect to one side of the CENTER of the timer. Check the wire markings carefully to be sure that you are connecting the FROM BREAKER wire to one side, and it's corresponding white wire beside it, and the TO WATER HEATER wire to the other. In most cases, the terminals will be marked according to current flow. Secure the stripped wires to the screws, using needle-nose pliers to bend the bared wire into a hook shape, thereby fitting it around the terminal screws better. Always run the wire from the left side of the screw to the right, so that as you tighten the terminal screw, the wire is drawn into the tightening friction, rather than twisted. Use this method to secure the black and white wires to their respective terminals. The bare ground wires can be intertwined, and one wire can be cut back, thereby securing only one wire thickness under the green grounding screw.
Next, set your timer for the configuration that suits you best. If everyone in your household sleeps from 11 PM until 7 AM, set the timer to be OFF until 6:30. That way the water heater is on for a half hour, and has plenty of hot water by the time your family awakes and hits the showers. Set the timer to be OFF after everyone leaves for work or school at let's say....8 AM. You can set it to ON again at the time that everyone gets back home....4 PM, 6 PM, or whatever the case may be, and off again at 11 PM. See the wisdom of heating water for 8 hours per day instead of 24 hours?
Reset the breaker that controls the water heater, or the MAIN breaker, and be sure to go look at each connection to be sure you haven't made a boo-boo. If you have, you'll know it soon enough. Sparks and smoke are a pretty good indication that you're not geting your Tim Taylor bumper sticker anytime soon.
One more time. If you're electrically-challenged, don't be afraid or ashamed to get a professional. A one-time-fee for an electrician might save you alot of anguish and misery in the event that you get your wires crossed. No pun intended.
And once it's done, you'll be enjoying hot showers when you want 'em, and dead-bolting your wallet when you're not!

I'm a home inspector in NY, and if you have any questions about home inspections, electrical, plumbing, structural, or HVAC issues, feel free to challenge me by emailing KReed@NY.nachi.org.