Before changing the temperature on an electric hot water heater, it's important to turn the power off prior to removing one of the panels. Find out about the two thermostats in an electric water heater with help from a master plumber and heating specialist in this free video on electric hot water heaters.
We are on an electric water heater, and we are talking about changing the temperature settings for your comfort level in your home. This is also a task that requires us to turn the power off so make sure first and foremost that you turn the power off before you ever remove one of these panels on the water heater. And then once again come back and double check yourself. Always double check yourself, because a lot of the times the boxes are not marked right or maybe the breaker doesn't work or there is something faulty in the electricity. These will hurt you if you don't check, and double check yourself. So what we do is we have our power off so we are going to go ahead and open up the cover, and get into our little mechanical room on our water heater here. The next thing we are looking for is power. There's two places that I check for this on a water heater. The first one is down here at the element. Typically if the power is on it is going to be towards this element, but there is also another place I check before I call it good. Now you can see that there is no voltage at this element here. The next one is a little trickier to get in to check I always reach up at the top here in the top corner just the corner itself, and I pull this plastic thing off. Don't worry it snaps right back on. The next thing I do is check up here for power at the top two screws, because there is power here all the time regardless. Sometimes the power transfers to the lower element, and that is why I say check both spots. If you are in one cover it is just as easy to pull this off, and check the top if you want to start there you will know for sure right away. You can see I have got no power at the unit period so we are safe to go ahead and work with this. Now the thermostat in these there's two thermostats in an electric water heater. There is an upper thermostat, and there is a lower thermostat. You ask why there is two the reason being is once you get the water to a certain temperature up here for that first hour of recovery you, it switches to the bottom to go ahead, and finish heating the rest of the tank. Now when it does that typically the bottom element is lower temperature on the thermostat by ten degrees or so than the top one due to a phenomenon called temperature stacking. Which is pretty simple if you think about it heat rises. It does the same thing in hot water, and in the tank itself. So your top is going to be a little bit hotter than your bottom so that they don't alternate wrong. It is something that a lot of people don't know about that is pretty important. So your lower element is usually one setting lower than your upper element, because each setting on these is about ten degrees. Now we get into the thermostat itself. Each one is a little bit different. Some of these thermostats have numbers on them, and some of them have letters on them. This one in particular has numbers on it, and as you can see it goes up to one hundred and fifty degrees Fahrenheit on this thermostat. This particular one. I like to see the hot water at about one hundred and ten degrees, especially when you are dealing with the elderly and small children, because it is potentially very, very dangerous. Any higher than that, and you have got some time still to move away from the hot water before it scalds your skin. Baby skin is very, very tender, and elderly people just can't move very fast so those are the two things that you have to be very aware of. Hot water is potentially very dangerous it is something that we all use every day. A lot of us end up taking for granted until your water heater goes out or goes bad, but it is something that we need to pay attention to temperature wise, because it can be very potentially dangerous. Now to change the temperature setting what you need is a smaller screwdriver as before we used a larger one or you may have a couple of different sizes. You are looking for a smaller screwdriver to do a job like this, because it has got to fit in the slot. What you do is you fit it in the slot, and you turn it clockwise to turn it up. Did you hear that click? That click means that it turned on. And you turn it counter clockwise to turn it down. This particular one on the top is set at one hundred and twenty-five. I don't recommend you set them this high just because that is a pretty high temperature. I like to see the top one set at the top site on an electrical water heater at about one hundred and ten to one hundred and fifteen degrees. And the bottom one one hundred and five to one hundred and ten. And you have got that stacking that happens. That makes your water heater very efficient. That's how you adjust the thermostat on this. Now there is also a redundant thermostat in the lower half once again that you have to adjust too.