Adjusting a Water Heater Thermostat
Adjusting the thermostat on your water heater is a little more difficult than adjusting the thermostat on your furnace. This thermostat is intended to be set once and forgotten about; in most cases, the factory settings are sufficient. Not sure whether this is the source of your issue? For a comprehensive overview of all of the issues that might arise with an electric water heater, see the article’Troubleshooting Electric Water Heaters ‘.
Too Little Hot Water
Are you considering boosting the temperature because you don’t have enough hot water to go around? Increasing the temperature is not the solution to this dilemma. It’s probable that you’re dealing with something else. It is possible that the thermostats themselves are not working properly, or that you have a burned out heating element. If you need further information on how to check to determine if your electric water heater thermostat or element is working properly, visit the articles ” Testing Electric Water Heater Thermostats ” and ” Testing Electric Water Heater Elements ”
It is necessary to conceal the water temperature changes for your electric hot water tank behind a couple of layers of insulation for safety reasons. Keep in mind that you must follow the ‘turning off the power’ recommendations while using an electric water heater. When you make this modification, you will be quite close to certain wires that have a significant amount of electricity flowing through them. When the temperature is set too high, there is a risk of burns. Water that has been heated to 160 degrees can provide you with a large amount of hot water.
- When there are youngsters in the house, it is especially important to set the thermostat to a conservative setting.
- It’s possible that the temperature of your water heater was set by the manufacturer.
- Do you truly want to make a difference?
- Hot water can cause serious burns if not used properly!
Shutting Down the Water Heater
Before you attempt to reach the thermostats, you must first turn off the electricity to the water heater and unplug it. Please see the article ‘How to Shut Down an Electric Water Heater’ for further information on how to do so. Pay close attention to the section on how to turn off the electricity. Ensure that the electricity is turned off at the heater and that the breaker has been properly identified and marked.
Locating the Thermostats
The majority of water heaters are equipped with two thermostats. Each of them is affixed to the edge of the tank. The thermostats are located on the side of the water heater, near two detachable plates that are attached to the water heater. To begin, you must first remove the metal covers that are located on the outside of the hot water tank. Then you’ll come across some insulation that has to be removed or pushed aside in order to reveal the thermostats and other electrical components.
The majority of models are equipped with a plastic cover that acts as an extra layer of protection. In order to make the modification, you will need to remove the plastic cover.
Adjusting The Thermostat
An adjustment screw may be made using a flat blade screwdriver by turning it clockwise or counterclockwise. It is possible that the heat descriptions will differ. It’s possible that it contains the real temps. The words ‘Warm’ and ‘Hot’ may appear on some of them, while others may have only letter designations (A, B, C).
If you have an electric water heater, it is rare that you will need to modify the temperature. In the vast majority of cases, the factory settings are sufficient. If you are experiencing a lack of hot water, increasing the temperature will not solve the problem. Another issue, such as a “burned out element” or a “faulty thermostat,” is most likely the cause of your problem.
How to adjust your water heater temperature
No one enjoys taking a cold shower. It’s much worse when you are scalded when the hot water is turned on. It is critical to correctly regulate the temperature on your water heater, not only for your health and safety, but also to save money on your power bill. Here’s how to regulate the temperature of your water heater to save money while also protecting your skin from sun damage.
The correct temperature range
It is recommended that your water heater be set within a specified temperature range for a variety of different reasons. A low temperature setting not only results in hot water that is merely lukewarm at best, but it can also promote bacterial development, which can lead to illnesses such as Legionnaires’ disease. This may be avoided by adjusting the temperature of the water heater to a level at which the bacteria Legionella cannot survive. A temperature of at least 140 degrees Fahrenheit (60 degrees Celsius) for water heaters is recommended by the Occupational Safety and Health Administration (OSHA) to prevent Legionella and other germs from growing in the water.
- The time it takes for third-degree burns to occur at 150 degrees Fahrenheit (66 degrees Celsius) is less than two seconds.
- Not to mention that a water heater that is set too hot might result in an excessively expensive power bill.
- The greater the distance between a faucet and the water heater, the greater the amount of heat that will be lost as the water flows, especially if the pipes are not insulated.
- When determining the appropriate temperature for your family and household, use your best judgment.
Make an adjustment, test it, and continue the process until you’ve found the ideal temperature setting for your house and water heater, which may take many attempts. Currently playing: Keep an eye out for this: Take a look inside the CNET Guide to Smart Living. 1:00
Adjusting water heater temperature
The interface used to control the temperature of a water heater will differ depending on the kind and model. Fortunately, the majority of water heater models can be modified in the same way. For example, most contemporary gas and electric water heaters are equipped with a thermostat concealed behind an insulated access panel. Electric water heaters are frequently equipped with two thermostats: one at the top of the tank and another at the bottom. Furthermore, most tankless water heaters include a display with a temperature reading as well as controls for altering the water heater’s temperature.
Turn on the water in the bathroom or kitchen sink and let it to run until the water is completely hot before using.
The process of adjusting a tankless water heater is quite similar to the process of adjusting your air conditioning thermostat. Adjust the temperature by using the digital control panel, which may be adjusted up or down as desired.
Gas or electric water heaters
Some gas water heaters include a dial towards the bottom of the device that may be adjusted simply by turning it – no tools are required for this operation. Nonetheless, most current tank water heaters (whether gas or electric) require a bit more effort, but the process is still straightforward and should only take a few minutes.
- Turning off the water heater’s electricity at the circuit breaker is the first step. To remove a thermostat(s), locate the access panel for the thermostat(s) and remove it using a screwdriver
- Remove the insulation by peeling it back. To adjust the thermostat, use a flathead screwdriver to turn it up or down.
- If your water heater has two thermostats, make sure they are both set to the same temperature. The temperature on the top thermostat should be a few degrees higher than on the bottom thermostat.
- Replace the insulation and re-install the access panel, if necessary. Reconnect the water heater’s power supply
- It is possible that you may need to relight the pilot light on a gas water heater.
Once you’ve made the necessary adjustments, you should wait at least three hours before checking the water temperature once more. It is possible that you may need to make more modifications in order to get the desired temperature. If you’ve increased the temperature and are still getting chilly showers, it’s possible that your hot water heater has to be serviced or completely replaced. Is the energy efficiency of your home high? Here are five different methods to find out. CNET’s Guide to Smart Livingis a one-stop shop for tips, techniques, and how-to guides that can help you live a more intelligent life.
How To Replace A Water Heater Thermostat
Please keep in mind that this content may contain affiliate links. This means that, at no additional cost to you, we may gain a small profit on purchases made via our links. The replacement of a onethermostat is an ideal time to replace both the upper and lower thermostats at the same time.
Testing the Thermostats on a Dual Element Water Heater
Because the majority of electric water heaters employ both an upper and a bottom element, the procedure outlined below is intended for these models only. A multimeter and a screwdriver will be required for this test. You can get an excellent, affordable multimeter online or at your local hardware shop for less than $20. Putting the UPPER thermostat through its paces:
- Immediately turn off the water heater’s electricity. Remove the panels that provide access to the elements, as well as the insulation beneath them
- Set the upperthermostat to the highest level possible with a screwdriver. Lower the lowerthermostat to its most conservative setting
- Restart the water heater by turning the power back on. Check the two wires above the reset button to ensure that electricity is being sent to the water heater. The voltage should be shown as 240 volts. Check the power on the upper element terminal screws with your multimeter to ensure they are not faulty. If there is no power, the thermostat is defective and must be replaced. Ensure that the lower thermostat is operational if there is electricity.
Putting the LOWER thermostat through its paces:
- Set the top thermostat to the lowest setting possible. Make sure that the lower thermostat is set to its maximum setting. Check to see whether there is voltage on the bottom component. Assuming the multimeter indicates that there is power at the element, take a few minutes for the water to warm up.
- Turn down the thermostat’s temperature setting and listen for an audible click, which shows that the thermostat is operating properly.
- To determine whether there is power at the element if there is no voltage, check the lower thermostat.
- In order to test the top contact screw, place one of the multimeter probes there and another probe on the metal shell of the water tank. It should display a voltage measurement of about 120 volts. The top thermostat, which supplies voltage to the lower thermostat, will need to be replaced if there is no indication of operation. Place one probe on the lower contact screw of the water tank and the second probe on the metal casing of the water tank if a reading is obtained. It should display around 120 volts. If this is not the case, the lower thermostat will have to be changed.
Electric Water Heater Thermostat Replacement
Before working on a water heater, make sure the electricity is turned off or the breaker is turned off. You will need to remove the access panel and the safety cover in order to change the thermostats (do this for both upper and lower access panels on dual element units).
Make sure the power is turned off with a voltage meter for the sake of safety before proceeding. Make a basic schematic of how the wires are linked to the diagram and label it accordingly. Remove the wires from the thermostat and set them aside.
In order for the thermostat to sense the internal water temperature, it must be secured in place by means of a particular bracket that clamps down on it tightly against the tank wall. Remove one side of the bracket by gently prying it out while twisting the other side of the thermostat upwards to prevent the bracket from locking back into place. Repeat the process on the opposite side. On dual element versions, repeat the process with the lower thermostat.
To purchase a replacement thermostat, bring the old thermostat(s) with you. Despite the fact that most thermostats are interchangeable, the greatest results are obtained by precisely matching the parts.
If the bracket was broken during the removal of the thermostat, you can purchase a replacement bracket at the same time. When the old bracket is removed, the new one should be placed flat against the tank and dragged downward until it is securely in place.
Each thermostat should be replaced by sliding it uniformly downward into the retaining bracket until it locks into position. Replace the wire in the exact same manner as it was removed. Replace the safety cover(s) and the access panel if they are damaged (s). Restore electricity to the water heater and allow it to run for one hour before checking the hot water pressure. If you believe that a heating element has failed as well, read How to Replace a Water Heater Element for more information.
Gas Water Heater Thermostat Replacement
Gas water heaters employ a different sort of thermostat system than electric water heaters. Generally speaking, on gas water heaters, the gas control valve, which incorporates both an adjustable thermostat and a heat limiting mechanism, is positioned on the outside of the unit, near the bottom. It may be distinguished from other components by the fact that it has temperature and pilot light controls. The thermostat on a gas water heater will need to be replaced, and the gas control valve will need to be replaced as well.
Refer to this page.
How to Set How Water Heater Temperature by Thermostat
You might be wondering how to adjust the temperature of your hot water heater. In this section, you will learn all you need to know about your gas or electric water heater thermostat, including how to adjust your hot water heater temperature thermostat and what temperature is optimum for hot water.
What’s the Right Temperature for a Hot Water Heater?
It’s an often asked question: what is the optimal temperature for hot water? Setting a tank-based hot water heater to 120 degrees Fahrenheit is recommended by the United States Department of Energy. If you have never changed the temperature of your hot water heater, it is most likely set to the 140-degree Fahrenheit level that is recommended by most manufacturers of hot water heaters. What is the significance of adhering to this temperature standard?
If the temperature setting on the water heater thermostat is set too high, the water will be excessively hot and might cause burning or scorching. If it is set too low, germs may be able to flourish, leading to the spread of water-borne illnesses.
How to Set Your Hot Water Heater Temperature Thermostat Setting
Before you make any modifications to the temperature thermostat setting on your hot water heater, you should first ascertain what the current temperature is set at so that you can establish how much you need to alter the settings. A conventional cooking thermometer may be used to quickly and accurately detect the temperature. You should calibrate your thermometer once you have determined the current temperature setting. Fill a cup halfway with cold water and submerge your thermometer until the temperature dial reaches 32 degrees, or the lowest temperature displayed on your thermometer’s gauge, and then remove it.
Meanwhile, locate the faucet that is closest to the water heater and turn it on until it is hot (while you are calibrating your thermometer).
If your thermostat is set too high, the temperature may be high enough to burn you.
Adjusting aGasHot Water Heater Temperature Thermostat Setting
The majority of gas water heaters are straightforward due to the presence of a clearly readable dial at the bottom of the tank’s bottom section. If you follow the methods outlined below, it is simple and straightforward to alter this dial.
- First, adjust the temperature by turning the knob to the hotter or cooler position, depending on the situation. After that, let it sit for a few hours (around three or four) and then check the temperature again. If the temperature is still incorrect, make another adjustment and repeat the process until the problem is resolved. Do you require assistance? Call Hackler Plumbing for a free estimate. If you want the services of aMcKinney plumber, we can assist you
Adjusting anElectricHot Water Heater Temperature Thermostat Setting
The process of adjusting the temperature thermostat setting on an electric hot water heater is a little more difficult, but still pretty simple. The vast majority of electric water heaters are equipped with two thermostats: an upper and a lower thermostat, both of which are placed beneath two control panels. Setting both thermostats to the same temperature can help to guarantee that your electric water heater operates as effectively as possible. One thing to keep in mind is that some tiny electric hot water heaters only have one thermostat.
Here’s how to adjust the temperature on your electric hot water heater thermostat:
Please keep in mind that you will want a screwdriver to execute the following procedures in order to alter the temperature of your water heater.
- Make sure your water heater is off by turning off the electricity. This may be accomplished by locating your circuit breaker and shutting off the electricity in the area surrounding your water heater
- Then, locate the thermostat(s) on your water heater and turn them on. Typically, they are located behind a control panel that is secured with screws. Remove the cover from the access panel using your screwdriver (s). To access the thermostat, you may need to remove the insulation from your heater if it is properly insulated. The thermostats will be controlled by a dial, and the dials will have a varying reading depending on the manufacturer of the heater. Once the control panel has been removed, you may change the temperature knobs to make the room hotter or colder according on your preferences in terms of temperature. Take care to set both thermostats to the same temperature setting if you have more than one. Replace the control panel covers and the screws with your screwdriver after they have been removed. After that, re-energize your water heater’s electrical system. After many hours, check the temperature of your hot water (about three to four). Continue to follow the above instructions until the water temperature reaches the required setting
- If it still does not, repeat them until the temperature reaches the ideal setting for your needs.
Other Considerations: Water Heater Thermostat Setting Safety
There is one thing you should be aware of: your water heater is fitted with something known as a temperature and pressure relief valve, abbreviated “T P valve.” These can become worn out over time, and one sign that they should be replaced is the presence of water leaking through. This is a very crucial safety feature. If your unit is old, or if your hot water heater pressure relief valve is leaking after it has been replaced, get it examined by a competent plumbing professional.
Test & Replace a Water Heater Thermostat: DIY Guide
We shall almost certainly all be confronted with the situation of a water heater that is not producing any hot water at some point in our lives. We have two options: either contact a qualified plumber or do it ourselves. Fortunately, most water heaters can be repaired reasonably quickly and inexpensively. There are two primary reasons for a water heater not working: If you’ve never checked or changed a water heater thermostat before, it might seem like a difficult process at first glance. It’s not too difficult.
When bathing or cleaning, no one enjoys using cold water.
If you are experiencing no hot water, we will need to examine the water heater thermostat and, if necessary, replace it. In this post, we will look at how to diagnose your electric water heaterthermostat and how to replace it if it becomes damaged or malfunctioning.
How Electric Water Heater Thermostats Work
When you begin to realize that your water heater isn’t operating as efficiently as it should, the thermostat is more than likely the source of the problem, or at the very least a contributing factor. No need to repair the entire electric heater when you can save yourself both time and money by just replacing the thermostat instead. Once you’ve gone over the following instructions, it will only take a few minutes. Electric water heater thermostats function by opening and shutting connections, which allow electricity to pass to the heating components of the water heater.
- Modern home water heaters are equipped with two heating components as well as two thermostats.
- The higher thermostat differs from the lower thermostat in several ways.
- It is quite rare for both thermostats to fail at the same time (although I do recommend replacing both when one fails).
- Whenever a lower heating element or thermostat fails, the top thermostat and heating element will take over and continue to heat water in the upper part of the hot water storage tank.
Are Electric Water Heater Thermostats Universal?
No, not all water heater thermostats are designed to be interchangeable. It is important to note that there are certain differences in thermostats between single-element and dual-element water heaters. Additionally, with dual-element water heaters, there is a differential between the top and bottom thermostats. In order to properly select a water heater thermostat, you must first determine the number of elements and the voltage of the water heater in question. It is possible to obtain this information from the data tag located on the side of the water heater.
The voltage is inscribed on the end of the heating element, and it may be read with a magnifying glass.
There are more than 50 different household tank-style electric water heaters available on the market, and the thermostats on the majority of them are designed to be interchangeable.
Typical household water heater thermostats are seen in this photo, which includes an upper and lower thermostat for each. Because it is located above the lower thermostat, the thermostat on the left has a high limit switch, which can be identified by the red reset button. The upper thermostat is in charge of controlling both the upper element and the lower thermostat, respectively. When you look at it from this angle, you can see the bottom thermostat, which regulates the lower element. For a replacement kit that includes two heating elements, upper and lower thermostats, and seals, we offer theRheem SP20060 Electric Water Heater Tune-Up Kit, which can be purchased on Amazon.com for about $30.
A universal upperthermostat produced by Rheem is what we’re looking at here. If you merely require a lower thermostat, the Rheem SP11695 Electric Thermostat is a good choice. It is a Rheem lower thermostat that is universal in use.
The thermostat seen here is for a water heater with a single heating element. The thermostat is very similar to an upper dual-element thermostat, with the only variation being the amount of wire terminals on the thermostat. In this case, the single element thermostat has just two terminals on the right side and four on the left side, as you can see in the illustration. If you require a single-element thermostat, the Camco 07843 Single Element Water Heater Thermostat with HLC is a good option to consider purchasing.
The following is a list of the supplies you’ll require:
- In addition, you’ll need a 1/4-inch nut driver or a flathead screwdriver, two Phillips screwdrivers, an analog or digital multimeter/voltmeter, and a new thermostat.
How to Test a Water Heater Thermostat for Continuity – Step-By-Step
We must examine the thermostats for continuity in order to identify whether or not the thermostat has failed. You’ll need an analog or digital multimeter for this, which you can get here. WARNING: Working with electricity is extremely hazardous and can result in death. Before dealing with wiring or electrical connections, be certain that the power is turned off. Follow these procedures to determine which thermostat is malfunctioning.
Step 1: Turn the power off
Make your go to your circuit board and locate the water heater breaker to switch off the power supply. Discover and switch off the breaker that is labeled “water heater” or “hot water” in the electrical panel box where the water heater is located.
Step 2: Remove the outside access covers
To remove the access cover from the upper and lower thermostats, use a 1/4-inch nut driver or flathead screwdriver to pry them off. Fold the insulation back over the thermostat to prevent it from being damaged. To keep the insulation out of the way, use tape to hold it in place. Remove the plastic cover that covers the thermostat on the inside of the house.
Step 3: Confirm power is off to the water heater
Make sure the water heater is not receiving electricity before working on it with a multimeter before doing anything on the thermostat. If you have a voltage stick, you may also use it to measure the voltage. Connect the top and legs of the multimeter at the same time, using the multimeter connectors. The meter should be set to zero. Touch each leg of the water heater while the black connector is in contact with it to ensure there is no electricity.
Step 4: Check the high limit reset button
If the manual reset switch, also known as the high limit reset button, has been tripped, it should be replaced. This button will trip on occasion if any of the following conditions are met:
- There is a short circuit between the thermostat contacts
- The thermostat is out of tune
- The heating element has failed
Step 5: Disconnect the wiring
Take a photo with your phone or a digital camera to use as a reference if it becomes necessary to identify which cables are connected to which terminal in the future. To detach the wiring from the thermostat terminals, unscrew the terminal screws using a Phillips #2 screwdriver and pull the wiring away from the terminals.
Step 6: Check the thermostat with a multimeter
Set the resistance of the multimeter to the lowest ohms possible (typically x10). Using your fingers, squeeze the probes together and adjust the needle to zero to calibrate your meter. To check the resistance of a digital multimeter, set it to the lowest possible value of resistance (usually 200), or, if your multimeter has an option for resistance with tone, choose it. Take one of the black probes from your multimeter and insert it into the screw terminal on the left side of the instrument. Take the red probe and connect it to the other left-side terminal on the other side.
This means that the thermostat is not functioning properly and must be replaced.
For a demonstration, please see the video above.
As soon as you have finished testing your water heater thermostat, you may either reconnect the wire and close the access cover, or you can proceed to the next step, which is replacing the thermostat.
Assuming you have decided that your thermostats do not require replacement, you may proceed to inspect your heating components. How to Test and Replace a Faulty Water Heating Element is a step-by-step guide that explains how to accomplish this in further detail.
How to Replace a Faulty Water Heater Thermostat – Step-By-Step
Once you’ve discovered which thermostat is faulty, it’s time to begin the process of removing and replacing it. Insider’s Tip: As previously said, it is typically a good idea to change both thermostats and heating components on a yearly or biannual basis. The reason for this is that if one of the heating components is beginning to fail, it has the potential to short out the replacement thermostat shortly after it has been placed, causing it to fail. Some of the stages will be repeated in this section.
For those who have not yet tested their thermostats, we will first go through the preparatory processes.
Step 1: Turn the power off
Make your way to the circuit breaker box and look for the switch labeled ‘Water Heater’ or anything along those lines. It should be turned off, making sure to turn off both switches if it is a 220v switch. If you’re not sure which water heater is causing the problem because of outdated stickers or labels, get a professional to turn them off for you.
Step 2: Remove the outside access covers
Remove the cover panel that corresponds to the thermostat that has to be replaced and set the cover panel aside. The coverings for water heater tanks are often located on the side of the tank. Ensure that you do not loose any of the little screws by using the 1/4-inch nut driver or a flathead screwdriver for this section. Remove the insulation from the thermostat as well as the plastic protective cover that covers it.
Step 3: Confirm power is off to the water heater
Each wire should be tested with your multimeter/voltmeter. This may be accomplished by grounding one of the lines and checking each terminal one at a time until the problem is resolved. Even if you have shut off the power at the circuit breaker, you should always double-check your work using one of these meters to ensure that you have not electrocuted yourself. Connect the top and legs of the multimeter at the same time, using the multimeter connectors. The meter should read 0 at this point. Touch each leg of the water heater while the black connector is in contact with it to ensure there is no electricity.
Step 4: Disconnect the wiring
Take a photo with your phone or a digital camera to use as a reference if it becomes necessary to identify which cables are connected to which terminal in the future. Disconnect the wiring from each terminal on the thermostat with a Phillips screwdriver #2. Remove the thermostat from the wall.
Step 5: Remove the defective thermostat
Gently remove the old thermostat by pulling outward on the clips and raising the thermostat up and out of the retaining bracket with your finger or a flathead screwdriver. Caution should be exercised to avoid breaking the retainer bracket. It is possible that breaking this retaining clip will result in the need to replace your water heater.
Step 6: Insert the new thermostat
Inserting the new thermostat into the retaining bracket that holds the old thermostat in place will allow you to precisely position the new thermostat. Reconnect the wires to the relevant terminals by twisting them together. If necessary, you can refer to the photograph you took previously for guidance. Check to see that each wire is securely linked to the next. Check to see that the thermostat is securely attached to the water heater, otherwise the thermostat may not operate correctly. After that, adjust the thermostat to the temperature you like for the water.
These modifications may be accomplished with the use of a flathead screwdriver.
The following is an insider’s tip: If you intend to replace your heating element with your new thermostat, you will need to empty the water heater first.
Some people propose doing a quick change without draining the storage tank; however, I do not encourage this because any mistakes might cause harm to the interior of your house. Check out our post on how to empty your water heater, as well as additional water heater care advice.
Step 7: Reattach the cover panels
Now that you’ve completed the replacement, it’s time to seal everything up and double-check your work for mistakes. Remove the plastic protective cover and insulation and replace them with new ones. Reattach the outside access panels if they have been removed.
Step 8: Turn the power back on
Following the completion of the installation, return to the electrical box and re-energize the circuit breaker (if necessary). Hot water recovery will take around one hour to complete, but you should be able to use hot water within 15 minutes after turning on the faucet. Over the next several days, make sure to check on the water heater on a regular basis.
Water Heater Thermostat FAQs
Electric water heater thermostats are typically pre-set by the manufacturer to 110 or 120 degrees Fahrenheit, depending on the model. You have the option of increasing the temperature to the maximum setting, which is typically 150 degrees Fahrenheit, if necessary (65 degrees Celsius). The maximum water temperature setting should be no greater than 120 degrees Fahrenheit (48 degrees Celsius), since a higher setting might provide a scorching threat to small children and the elderly.
Should water heater thermostats be set to the same temperature?
In fact, the top and lower thermostats should both be set at the same temperature. The dip tube is responsible for delivering cold water to the bottom of the tank. Having consistent settings across the tank helps to keep the temperature consistent throughout the tank.
What would cause a water heater thermostat to burn up?
A malfunctioning heating element, a power surge, or just the passage of time can cause a water heater thermostat to burn up. When internal components of water heater thermostats wear out, they become faulty and fail. Even with regular electric currents, an older thermostat may experience failure. If the manual reset switch on your water heater thermostat does not work, the thermostat will need to be repaired or replaced. Replacement of both thermostats and heating elements should be done at the same time because if one of the heating elements is beginning to fail, it may cause the new thermostat to short out shortly after it is installed, which is not recommended.
Simply said, that’s the whole story! Water heaters aren’t too difficult to maintain, and replacing a thermostat can be completed in a matter of minutes if you know what you’re doing and have the right tools. The most important thing to remember while working with electrical equipment is to avoid taking shortcuts. Although it is possible to change your water heater thermostat in a short period of time utilizing the correct skills and tools, doing so is not recommended. DISCLAIMER: The information provided on HomeInspectionInsider.com is not intended to be professional guidance.
It is owned and operated by Hubert Miles who is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by placing advertisements and links on their websites that direct traffic to Amazon.com (hereinafter referred to as “Amazon.com” or “Amazon.com Associates Program”).
As an affiliate, HomeInspectionInsider.com participates in a variety of affiliate programs with other websites. Hubert Miles receives a commission for recommending visitors and commerce to these businesses.
How to select and replace thermostat on electric water heater
|Replacement steps start here|
|Power if OFFDo not empty water out of heater||Turn power OFF Turn off 20 or 30 Amp circuit breaker to 240V water heaterSee basic water heater wiring diagram Or 20 Amp circuit breaker to 120V water heaterCheck label on side of water heater for appliance voltageFigure volts amps watts Wattage is stamped on end of elementsee example|
|Never assume power is OFF/ Use non-contact voltage tester Use non-contact voltage tester on timer, on wire, on outlet to see if power is present.Press button on tester, if single beep then no power is present. If continuous beep then power is present.Never stand on bare ground, always stand on dry boards, do not hold or touch anything metal when working on timer or water heater that has power, tape tester leads to wood sticks, never touch wet water heater, or flooded water heater, or timer that had a short or fire without turning power OFF.Buy:Multimeters at AmazonBuy non-contact voltage tester at AmazonElectric testers at AmazonShop Amazon – Industrial and scientificShop Amazon – Industrial Electric Products|
|How to find age of water heater||How to use ordinary tester/ 120, 208, or 240V:Stand on dry boardsNever touch wet water heater unless power is OFFTape tester leads to wood sticks1. Test black wire to ground wire2. Test black wire to white wire3. Test white wire to ground wireIf indicator lights up, then electricity is present.|
|Newer tanks have foam insulation that may need to be cut back. Insulation must be re-installed.||Do not empty water out of heater Not necessary to wait for water to cool. Can be done with hot water inside tank.Power must be OFF.Use screwdriver to remove covers and insulation from tankSome 240Volt tanks have single access door and single thermostatBuy new parts that match oldBuy parts at hardware storeThermostats and elements are generally interchangeable between brands of electric water heaterException is Whirlpool energy-smart shown lower on page.Thermostats usually covered with plastic protector shield.New protector shield packaged with some new thermostatsPurpose of protector is to protect homeowner from electrocution when pushing reset button or adjusting temperature when power is ON.Older heaters may not have plastic shield.Buy:Upper element terminal protectorLower element terminal protector|
|Take photo of wires. before startingTake photo of wires or draw picture showing location of each wire|
|Larger imageSee large image of overall wiring diagram Wire colors can varyTake photo of wiring before starting.See upper thermostats showing numbers||Steps to replace thermostat Instructions are same for both upper and lower thermostatsPower is OFF, and tested that power is off using steps aboveUse digital camera and take photo of wires or draw picture showing location of each wireRemove wires from thermostatThermostat is held in place by metal spring that snaps over ears on thermostatPull back metal spring on both sides (make a tool using piece of coat hanger wire)Slide out old thermostatPut new thermostat in place, wiggle thermostat around to make sure it is held flat and tight against tank by metal spring Thermostat reads temperature through surface of metal tankUse screwdriver to adjust temperatureSee images showing how to adjust temperature to 120�(or higher if hot water runs short)Re-connect wirestighten screws very firm against copper wireImportant. Push-in red reset button firmly to make sure it is engagedAfter thermostat is replaced, put factory insulation back over thermostat Insulation must cover thermostat to avoid higher water temperatures than desired set point Tank must be full of water or elements will instantly burn outTurn power ONPut ear against water heater to hear bubbly fizzing sound that says water heater is ‘on’If tank is fully heated, water heater will not turn on. If tank is partially heated, then lower element will turn on. If tank is cold, then upper element will turn on.How it works Put access doors back on tank Access doors and insulation are required for thermostat to read correct temperatureIf water heater is still not working,see troubleshooting|
|Burned thermostatWhat caused it?Electricity found path from terminals on thermostat to bare metal tank. But fire did not spread because tank factory-installed covers and insulation were on side of tankAlways connect ground wire to water heaterAlways keep insulation and cover installed on tank.||Inspection finds Burned thermostat or melted wire Turn power OFFReplace partTest wiresTest wires with MultimeterBuy:Multimeters at AmazonResourceHow to test water heater wires|
|Fire safety||Fire safetyAll wires must be same gauge (same diameter). Or connect different gauge wires using push-on wire connectorsOnly copper wire used.Solid wire only. Never use stranded wire.Only copper under screw plate, no insulation under screw plate.Maximum 2 wires under screw plate.Wires must be fully inserted under screw plate. And screw plate very tight against wires.Wires cannot run over top of thermostat or elements, and must be pushed aside.Wires can run over top of other wires, but not at point where wires are making connection to either element or thermostat.|
|Use push-on wire connectors when wires are too shortBuy:Push on wire connectors at AmazonRed 3P connector (shown) for 10-14 gauge wireYellow 4P for 12-18 gauge wire|
|Thermostat must sit flat against tank Wiggle thermostat to make sure it sits flat against tankThermostat sits flat against tank wall so temperature reading is accurate and water heater is protected from overheatingAccess doors and insulation must be put back over thermostat to avoid higher water temperatures than desired set point, which leads to overheating, which will trip ECO reset.|
|See larger||Double-check thermostat wiringCompare wiring with illustrationResources:How to wire thermostatsHow water heater thermostats workRed reset button:ECO energy cut off turns off power to water heater when temperature reaches 150�-170�|
|Adjust temperature on thermostat using screwdriver. Recommended temperature is 120 degrees F for efficiency and to avoid scalding water.If home is running short of hot water, turn temperature up.Thermostat settings are approximate. Calibration is different for each thermostat. Use cooking thermometer to measure water temperature when exact temperature is needed.Problems from high temperature setting include higher bill, faster sediment build-up. Minerals can distill out of water when water is above 140 degrees.Water expands with higher heat. TP valve releases water. Pressure should not exceed 80 psi.Resources:How to adjust water heater temperature9 ways to save with water heaterTest and replace TP valve.Install expansion tank.Inspect for leaks once per year.Test for high water pressure over 80psi that can damage tank and pipesFormulas and terminology|
|Insulation and cover must be over thermostat. Exposing thermostat to cool room temperature will cause tank to overheat.Thermostat cannot read correct temperature unless covered correctly.Buy:Upper element terminal protectorLower element terminal protectorResourceTroubleshoot electric water heater|
|Inspection finds leak/ rust around elementResources:Replace element and gasketInspect anode rodLeaking water heater resourcesHow to install electric water heater|
|Circuit breakers/ push fully OFF / and then fully ONWater heater is tripping breakerHow to replace circuit breakerHow to wire gfciCan AC breaker be used for DC breakerHow to reset circuit breakerNot enough space for circuit breakersCircuit breakersHow to install subpanelWhy you need ground wireMatch breaker and wire sizeHow to wire subpanelSee inside breaker boxHow to wire safety switchHow to wire whole house surge protectorFigure volts amps and wattsFigure correct wire and breaker|
|Add another thermostat to water heaterFor example turn off power to recirculation pump that pumps water from solar panel or secondary tank.or control electric water heater from the gas water heater. or turn off solenoid valve that turns off gas line. or connect to indicator light to notify when tank reaches set point. or connect to solenoid water valve that turns on hot water. Thermostat is mechanical and will work with 12-12 Volt AC-DC, 120-208-240, 277 volt AC electricity.ResourceAdd another thermostat to gas or electric water heater|
|Bi-metal thermostat with magnet for all kinds of DIY projects||Bi-metal thermostats/ fireplace, furnace, cooling fan etc Magnetic. no bracket needed.ON at 120F / OFF at 90 F. use relay if you want OFF at 120F and ON at 90FRated 15 amps @ 120 Volt. Works with any voltage 12-24-28-120-208-240-277Mechanical switch requires no voltage to operate switchBuy90-120 degree F thermostat:Magnetic thermostat kit at AmazonThermostat switches at AmazonAdjustable thermostat 90-120Oven thermostatResources:Bi-metal thermostat switch limitsT36 therm-o-disc|
How to replace an electric water heater thermostat
Replacement of the thermostat in an electric water heater is covered in detail in this do-it-yourself repair guide. The thermostat regulates the temperature of the water by turning on and off the heating element on and off. If the thermostat stops operating, the element will either not turn on at all, resulting in cold water, or it will stay on for an excessive amount of time, resulting in scorching water. Replace a faulty thermostat with a replacement part that has been approved by the manufacturer.
- How to replace the thermostat on an electric water heater with this video repair instruction.
- Warning: It might be dangerous to do repairs or maintenance on appliances or power equipment without proper training.
- In an effort to decrease the danger, make use of the right tools and safety equipment as specified in the applicable handbook and adhere to all of the guidelines.
- A qualified technician, on the other hand, should be called in for some repairs or maintenance.
How to Test a Water Heater Thermostat and Replace it if Needed
Check the thermostat if your hot water isn’t getting hot enough, according to the instructions. Do you, on the other hand, know how to test a water heater thermostat? And, if it turns out to be problematic, do you know how to repair the thermostat on your water heating system? All excellent questions, all of which will be addressed in this essay! There are two possible explanations for why your electric water heater isn’t heating the water. Perhaps the heating element or the thermostat is not functioning properly.
It’s actually not as difficult as it appears!
Water Heater Thermostat Basics
The electric water heater thermostat is positioned on the front of the water heater tank, beneath an access panel that provides access to the tank. The thermostat is in charge of maintaining the temperature of the water in the tank. It does this by opening and closing connections in order to switch on and off the flow of electricity to the heating elements, which are immersed in the tank and are responsible for heating the water in the tank. There is a bi-metal switch that is flush with the wall of the water heater’s tank and operates the water heater.
The bi-metal switch on your water heater will open when the temperature of the thermostat reaches 120°F, preventing electricity from flowing to the heating element.
When the temperature falls below the 120°F set point, the polar opposite occurs. The bi-metal switch is closed, and power is permitted to flow to the heating element through the breaker circuit. This video will demonstrate how the thermostat on your water heater operates. Take a look at the video
Identifying Which Thermostat is Faulty
With a capacity of 30 gallons or more, the vast majority of water heaters employ two heating elements, each with its own thermostat. It is hooked into the thermostats so that only one heating element is activated at a time. The upper thermostat is responsible for bringing the top third of the water in the tank to the desired temperature. After that, it shuts off and switches the electricity to the lowest thermostat setting. The two thermostats are not identical, and if one fails, the water heater will react in a different way than if the other fails.
How to Identify Which Thermostat Failed
- Water heater will cease heating water completely if your higher thermostat (or heating element) is faulty. Because the top thermostat is in charge of the lower thermostat, if the upper thermostat fails, the lower thermostat will never turn on. Theft of the Lower Thermostat- If your lower thermostat (or heating element) fails, you will either notice that the hot water is tepid or that the hot water is quickly depleted. Due to the fact that the higher thermostat will signal the heating element to heat just the top third of the water in the tank, but the lower thermostat is defective and is unable to switch on the bottom heating element, this occurs.
How to Test a Water Heater Thermostat
First and foremost, you must ensure that there is no discontinuity. You’ll need a Phillips and a flat head screwdriver, as well as a multimeter, to complete this task. Always switch off the electricity to your electric water heater before starting any work on it. Then double-check that the power has been turned off. Here’s how it’s done:
Shut Off the Power to Your Water Heater
- At the main electrical panel, turn the breaker to the OFF position. Remove the thermostat’s access cover and set it aside. Removing the insulation and plastic protective cover is the first step. Touch one of the multimeter’s probes to a grounded metal object (such as the tank casing, which is unpainted metal)
- Connect the second probe to each thermostat terminal as well as the terminals of both heating elements. At all times, the multimeter should display zero voltage (Zero). To visually see how to switch off the electricity to your water heater, watch the video below.
How to Test a Water Heater Thermostat for Continuity
It’s time to check the thermostat on your water heater now that the electricity has been turned off at the main electrical panel. First and foremost, you must understand what you are doing.
- Check to see if the reset button has been pressed. If it has, go ahead and reset it
- Otherwise, wait. Remove the wires from the thermostat and set them aside. Pay close attention to how they are linked together.
- By pressing the reset button, one of the multimeter leads will be connected to the left side terminal. The other multimeter lead to the other terminal on the left side of the reset button should be touched as well. If the thermostat has continuity, the multimeter should show a reading close to one hundred percent. This indicates that the thermostat is malfunctioning and must be changed
- Otherwise, this indicates that the thermostat is working properly. Rerun the test on the right-side terminals by pressing the reset button one again.
Step number three.
- Test the lower area of the thermostat by connecting one lead to the common terminal (located next to the temperature setting) and the other lead to the left heating element terminal
- This will reveal whether the thermostat is functioning properly. If the temperature of the water in the tank is lower than the thermostat’s set temperature, the resistance reading on the multimeter should be near to 0 ohms. Move the lower lead from the left heating element terminal to the right heating element terminal by pulling it up and out. The continuity indicator on the multimeter should indicate “NO continuity.” If the temperature of the water in the tank is higher than the thermostat’s set setting, you should observe the polar opposite of what you want. If the upper thermostat is functioning properly, you’ll need to check the lower thermostat as well.
- Disconnect the power cables from the lower thermostat and turn off the electricity. Using the first lead, connect it to a single terminal and the second lead to the other terminal
- If the water temperature is lower than the thermostat’s set temperature, the resistance shown by the multimeter should be near to 0 ohms. If the water temperature is higher than the thermostat’s programmed temperature setting, the multimeter should show no continuity
- Otherwise, it should. A thermostat with the opposite reading indicates a defective thermostat.
Watch the Video
Generally speaking, if you’ve decided that one of your water heater’s thermostats is malfunctioning and must be changed, it’s preferable to repair them both at the same time. Thermostats are available for purchase singly or as part of a set.
Buying a Tune-up Kit
Perhaps you might consider getting a tune-up package, which will contain both the upper and lower thermostats, as well as two new heating elements for your furnace. It may cost a few dollars extra, but you’ll notice a significant improvement in the way your water heater functions in most circumstances. This is especially beneficial if your water heater has at least a few more years of useful life left in it. Tune-up Kit for Any Vehicle The ZERO EWH-01 Tune-up Kit is designed to work with the majority of electric water heaters.
An OEMtune-up kit for electric water heaters is also available from Rheem.
Make sure the heating elements are the suitable size and type for your water heater.
Buying Upper or Lower Thermostats
Although it is usually a good idea to repair both thermostats at the same time, there are situations when it is just more convenient to replace only the malfunctioning one. This is especially true if you have plans to acquire a new water heater in the near future and are only attempting to get your present water heater up and running until you can make the purchase. Camco Thermostat, Upper Thermostat This upper thermostat from Camco offers a built-in reset button, changeable temperature settings, and a one-year guarantee on the mechanical components.
If you choose, Rheem also has an OEM upper thermostat that you may use. If you want a lower thermostat, theCamco 8123is a decent, low-cost choice, and of course,Rheem also sells one in this configuration.
Single Element Water Heaters
Although we’ve concentrated on double-element water heaters, certain models, particularly those with tanks of 20 gallons or less, may heat water with a single heating element. These water heaters are connected in a different way and require a single element thermostat to function properly. They may appear to be very similar to an upper dual element thermostat, however they have fewer wire terminals than an upper dual element thermostat. Camco Thermostat with a Single Element The Camco 07843 Single Element Thermostat is equipped with a built-in safety switch, changeable temperature settings, and a protective cover for further protection.
How to Replace a Water Heater Thermostat
Water heater thermostat replacement is a simple process that you should be able to complete on your own without any difficulties. Although many homeowners are comfortable doing the work themselves, many choose to employ the services of a professional plumber. You’ll need a Phillips and a flathead screwdriver, as well as a multimeter and your new thermostat to complete this project. Make certain that the thermostat you select is compatible with your water heater.
Shut Off the Power to Your Water Heater
- At the main electrical panel, turn the breaker to the OFF position. Remove the thermostat’s access cover and set it aside. Removing the insulation and plastic protective cover is the first step. Touch one of the multimeter’s probes to a grounded metal object (such as the tank casing, which is unpainted metal)
- Connect the second probe to each thermostat terminal as well as the terminals of both heating elements. At all times, the multimeter should display zero voltage (Zero).
- Disconnect the cables from the thermostat. Pay attention to how they’ll be reconnected
- This is important. To remove the thermostat from the retaining bracket, carefully lift it out.
- The old thermostat should be replaced with a new one. Check to see that it is the proper thermostat for your heater. Check to see that the rear of the thermostat is snugly pressed against the tank’s inside. The cables to the thermostat should be reconnected. Replace the protective cover with a new one.
Step number three.
- Check and make necessary adjustments to the temperature setting to 120°F. Remove the insulation and access cover and replace them. Activate the water heater’s power supply
Watch the Video
Some frequently asked questions about water heater thermostats have been included below for your convenience:
Are Electric Water Heater Thermostats Universal?
No. Some water heaters employ two heating elements, while others only use a single heating element to heat the water. These are not the same, so you’ll want to make sure you get the right one for your water heater before buying it. Aside from that, in dual-element water heaters, the lower and top thermostats are not the same and cannot be used in combination. Because the top thermostat is bigger and contains more terminals than the lower thermostat, it is preferred. As a recommended practice, always check the information tag on your water heater to ensure that you are purchasing the suitable thermostat for your system.
How to Reset a Water Heater Thermostat?
If your thermostat has tripped, you can remove the insulation from the tank by opening the access cover on the front of the tank. On the thermostat, there should be a red button to press. To reset the device, simply press it in. If it trips again, you may be dealing with a more significant issue (see below).
What Causes a Thermostat to Trip?
There are a variety of reasons why a thermostat may malfunction. A defective thermostat or heating element are the most typical causes, but it can also be caused by a poor electrical connection or even a malfunctioning reset button. If you are having trouble determining the source of the problem, you should consult with a professional plumber.