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.
- The lower thermostat should be adjusted to the lowest setting. Make sure the lower thermostat is set to the highest possible level. Inspect the lower part to ensure that it is properly charged with voltage (see below). Allow a few minutes for the water to boil up if the multimeter indicates power at the element.
- 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.
Step 2
Before working on a water heater, be sure the electricity is turned off or the breaker has been turned off. The access panel and safety cover must be removed in order to replace the thermostats (do this for both upper and lower access panels on dual element units). Use a voltage meter to ensure that the power is turned off for your own safety. Using a simple graphic, show how the wires are linked to the schematic diagram. Remove the wires from the thermostat and put them somewhere safe for now.
Step 3
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.
Step 4
To purchase a replacement thermostat, bring the old one(s) with you. In spite of the fact that most thermostats may be swapped out, the greatest results are obtained by precisely matching the components.
Step 5
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. Do you need to change a water heater thermocouple or a water heater element? Refer to this page. Take a look at our articles on the subject!
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.
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. When making a purchase, it is important to thoroughly read the product description.
Dual-ElementThermostats
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.
It is a Rheem lower thermostat that is universal in use.
Single-Element Thermostats
Typical home water heater thermostats are seen in this shot, which includes an upper and lower thermostat for each unit. Because it is located above the lower thermostat, the thermostat on the left has a high limit switch, which can be distinguished by the red reset button. It is controlled by the higher thermostat, which also regulates the lower thermostat. On the right is the lower thermostat, which is in charge of controlling the lower element. When looking for a replacement kit that includes two heating elements, upper and lower thermostats, and seals, we propose theRheem SP20060 Electric Water Heater Tune-Up Kit, which can be found on the Amazon website.
It is a Rheem upperthermostat that is ubiquitous in use.
In this case, it’s a Rheem lower thermostat that’s universal.
- 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
Make sure the water heater is not receiving power before working on it with a voltmeter before doing anything else. A voltage stick can also be utilized in this situation. Apply pressure to the top and legs simultaneously with the multimeter connections. When the meter should read 0, it should be considered accurate. Touch each leg of the water heater when the black connection is in contact with it to ensure there is no electricity flowing through the water heater system.
- 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.
- 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. Following the testing methods provided above, you should be able to skip to Step 5. For those who have not yet tested their thermostats, we will first go through the preparatory processes. We’re going to start from the beginning.
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 replacement, it’s time to seal everything up and double-check your workmanship. The protective cover and insulation made of plastic should be replaced. Reattach the external access panels if they have been taken off before.
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.
Final Thoughts
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.
5 Easy Steps For a DIY Water Heater Thermostat Repair
Hot water is a luxury that most of us can’t imagine not having at our disposal. Consider all of the numerous ways you use hot water in your daily life – for dishes, for clothing, for bathing, for mopping, and so forth. Having a malfunctioning water heater in your home will give you a sense of how critical and vital your water heater is to your daily routine and way of life. Water heaters are available in a variety of configurations, including electric, propane, and natural gas. Each operates in a slightly different way, but they both provide the same purposes, which include heating water and storing it until it is needed again.
When the thermostat in your water heater malfunctions, you will be unable to monitor or control the temperature of your hot water.
When Should You Repair Your Water Heater Thermostat?
When it comes to your water heater, there are a few tell-tale indicators that you should be aware of and pay attention to. Some of the indicators listed below may indicate that your water heater needs to be serviced or repaired.
Your Water is Too Hot
The presence of very hot water is a strong sign that your thermostat is set too high. Other external variables, such as the changing of the seasons, may also contribute to this problem, and you should adjust the suggested setting when the weather changes from cold to warm. If you are unable to reduce the temperature of your water, you may need to replace the entire thermostat or do a thorough inspection for any wiring problems. Find a professional to assist you in resolving thermostat wiring difficulties in order to avoid injury or more harm.
There’s Not Enough Hot Water
Cold weather conditions can also contribute to a lack of hot water availability. It’s possible that you have chilly pipes that aren’t properly insulated, or that your thermostat has failed. There are a variety of additional concerns that might arise, including loose wiring, broken equipment, and a hot water tank that is too small for your needs.
Water Takes Too Long to Reheat
Electric water heaters are notorious for taking a long time to heat up. Heater reheating time is approximately twice as long as it takes for a gas heater to heat up. If you notice that it is taking even longer to heat, it is possible that there is an issue with the heating components or thermostat.
A Step-by-Step Guide to Repair a Water Heater Thermostat
A water heater’s thermostat is responsible for regulating the temperature of the water. It is possible that if the temperature is adjusted too low, the water will cool before it is sent to the faucet. Furthermore, if the temperature is set too high, you run the danger of being burned or scalded by the water temperature that is emitted from the faucet. In the event that you do not have hot water, here is how to fix a thermostat:
- Figure out where the upper and lower thermostats are
- The power supply of both thermostats should be checked. To establish whether the thermostat will or will not function, press the button to reset it one more. If there is no power to the upper system, the thermostat should be replaced. The top heating element should be replaced if your upper system is getting electricity but there is no hot water coming out of it.
If the temperature of your water isn’t just correct, you may easily adjust the thermostat by yourself.
Here are three simple things that Sacramento people may do to protect themselves.
1. Locate Your Water Heater’s Temperature Control Knob.
When the temperature control knob is turned, it is connected to the heater’s heat source, which is normally red and positioned on the front, lower center area of the heater’s body.
2. Look for the Small Black Line or Arrow above the Knob.
A temperature setting may be labeled “warm” or “hot” in this area, depending on the current temperature setting. This can alternatively be shown by a black line (120 degrees Fahrenheit) or a white line (140 degrees Fahrenheit) (105-110 degrees Fahrenheit).
3. Adjust the Temperature Somewhere Between 105 and 120 DegreesFahrenheit.
What factors should you consider before deciding whether to repair or replace your water heater? In most cases, if there isn’t a leak, the damage is minimal and can usually be fixed quickly and simply. For example, tank wear and rust are two of the most prevalent types of problems you’ll observe with your water heating system. These are often minor concerns that may be resolved with minimal effort. If your tank is leaking, it is preferable for you to replace it rather than attempt to fix it.
Additionally, leaking tanks can result in hazardous water damage to your personal belongings, and if the water isn’t cleaned up immediately, mold-breeding fungus can form.
- The drain valve
- The cold water inlet
- And the hot water inlet. In addition to the anode rod, the dip tube and the pressure release valve are also included.
Water inlet for cold water; The drain valve; Water inlet for hot water; In addition to the anode rod, the dip tube and the pressure release valve are also included in the package.
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.
- O.
- 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 Replace a Water Heater Thermostat
Depending on why your water heater has stopped operating, it may have failed to obtain a temperature measurement. If this is the case, do you know how to change the water heater thermostat? If this is the case, you’ve come to the correct spot. Before purchasing a new replacement component, you should ensure that your old thermostats have been thoroughly tested.
The replacement of thermostats is a waste of time and money if the thermostats are not the source of the problem. These are the operating instructions for electric water heaters. Replacement of the thermostat on a gas water heater entails replacing the complete gas control valve.
How to Test a Water Heater Thermostat
Most electric water heaters have two thermostats, and it is possible that one or both of them are malfunctioning. Keep in mind that the upper thermostat is responsible for supplying voltage to the lower thermostat. Here’s how to figure out what has to be replaced:
- One or both of the two thermostats found in most electric water heaters may be malfunctioning. Remember that the top thermostat is responsible for supplying voltage to the lower thermostat. Here’s how to figure out what has to be replaced: 1.
- The majority of electric water heaters have two thermostats, and one or both of them may be malfunctioning. It’s important to remember that the higher thermostat is responsible for supplying voltage to the lower. Here’s how you figure out what has to be replaced:
Replacing a Water Heater Thermostat in 8 Steps
Keep in mind that this is for electric water heaters only:
- First and foremost, turn off the electricity at the breaker
- Remove the access panel(s) and insulation so that you may gain access to the thermostat and adjust it (s). You may have one or two access panels on your property. The majority of water heaters contain two heating elements/thermostats. Make use of the voltage meter to ensure that the power is entirely turned off. Photocopy the wiring within each panel so that you can refer to it later when you’re putting everything back together again. Remove the thermostat’s wire from the wall
- To remove the thermostat, you must first remove the complete bracket that keeps it in place. Pry out each side one at a time with a twisting motion, being careful not to damage the skin. Don’t try to force it, or you’ll end up breaking it. It’s important that you don’t have to replace that part as well, so take your time with this step and do it correctly. Replace the wire after inserting the new thermostat into the bracket and securing the bracket in place. Reconnect the electricity and let your tank a few minutes to warm up before using it.
Enjoy Your Newly Working Water Heater
This job is doable by even the most inexperienced home repair beginner, but that doesn’t mean you should. If this appears to be too much for you, get professional assistance. If you found this post useful, please spread the word about it among your social media contacts. Bradford White and other well-known brands are available at PlumbersStock. If you are looking for a new water heater, you have come to the correct spot. If you require further information on water heaters, please refer to our assistance resources or thisWiki page on the subject.
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 a Water Heater Thermostat (Ultimate Guide)
You’ve turned on your hot faucet, but the water is suddenly too hot. Have you tried altering the temperature but found that nothing worked? After that, it’s most likely time to replace the thermostat on the water heater. If your water heater has a thermostat, changing it shouldn’t be a major undertaking. We’re here to lead you through the process and teach you a little bit about what to look out for along the way.
How to Replace a Water Heater Thermostat
Replacing a thermostat is a very simple task, albeit the technique varies depending on how many heating components are present in your tank. The majority of electric water heaters on the market today have two heating components. Smaller units or older versions are more likely to have only one. Your tank is equipped with a thermostat that corresponds to each of those heating sources. If your unit has a dual element system, it most likely does, and it will require two thermostats that are similar.
We’ll concentrate on the twin element system because it’s the most common type of water heater.
Because the top thermostat is responsible for supplying electricity to the lower thermostat, replacing both saves time.
- A multimeter or a voltmeter is required. Screwdriver
- A screwdriver with a flat blade
- Various colored tapes or bandages are used. A new thermostat, which should be as close to the old one as feasible
- And
1.Turn the Power Off
Multimeter or voltmeter are both examples of measurement instruments. Screwdriver; Screwdriver with a flat blade; tapes or bandages in a variety of hues When possible, a replacement thermostat that is similar to the old one;
2.Check Upper and Lower Thermostats
First and foremost, it is critical to thoroughly inspect the thermostats before they are replaced. This will necessitate the use of the multimeter and a screwdriver. Begin by removing the access panels and the insulation that has been placed in front of the elements. Next, using the screwdriver, raise the top thermostat to its maximum setting. Then reduce the temperature on the bottom thermostat to its lowest level. Reconnect the electricity to the water heater if it has been disconnected. Check for voltage with your multimeter or voltmeter to see if it is coming through.
Following that, attach the multimeter to the upper element using the terminal screws.
Whether there is electricity, check the lower thermostat to see if it is working.
To remedy this, crank up the lower thermostat to the maximum setting and down the higher thermostat to the lowest setting on the thermostat.
After that, look for voltage. If there is voltage, it is just a matter of replacing the higher thermostat. However, if there are no evidence of power, they should be replaced together.
3.Turn the Power off Again
After you’ve determined that one or both of the thermostats in the unit need to be replaced, turn the power back off to the unit. Do not proceed if the water heater is still connected to the circuit. To check for voltage, use a voltmeter or a multimeter to measure the current.
4.Remove Bracket
Turn off the electricity to the device once again once you’ve determined that one or both thermostats need to be changed. If the water heater is still connected, do not continue. To check for voltage, use a voltmeter or a digital multimeter.
5.Disconnect the Wires
After you’ve determined that one or both of your thermostats need to be replaced, turn the power off to the device once again. If the water heater is still connected, do not proceed. Check for any voltage with a voltmeter or multimeter.
6.Remove the Thermostat
After you’ve determined that one or both thermostats need to be replaced, turn the power off to the device once more. Do not proceed if the water heater is still connected. To check for voltage, use a voltmeter or a multimeter.
7.Install New Thermostat
Keep in mind that the replacement thermostat must be an exact replica of the one that was replaced. If this is not the case, it may not function properly or at all. Take your new thermostat and secure it in place with the retention clips on either side. Adjust its position so that it is flush with the tank wall. Reconnect the circuit wires to the appropriate screw terminals on the circuit board. Check to ensure that they are the same as the original wiring. Color-coded tape comes in helpful at this point; simply recall where each color should go and remove the tape.
8.Set the Temperature
Set the temperature on the thermostat once it has been installed. Use the flat-bladed screwdriver to carefully adjust the thermostat to the temperature you want it to be. It’s important to remember that the optimal temperature for a water heater is 120 degrees Fahrenheit. This is beneficial for a variety of reasons, including efficiency and safety (1).
9.Replace Insulation and Cover
You’re nearly finished! Replace the insulation so that it completely encircles the thermostat and its electrical components. Replace the compartment lid and tighten the screws to keep it in place. Reconnect the electricity at the breaker box and allow the device to warm up for at least two hours before using it. Turning on the faucet after two hours will allow you to check the temperature of the water.
Are All Thermostats the Same?
Congratulations, you are nearly finished! In order to protect the thermostat and electrical components, the insulation must be replaced. Insert two screws into the compartment cover to hold it in place. Allow for at least two hours of heating time after re-entering the power through the breaker box. Turning on the faucet after two hours will allow you to check the water temperature.
Gas Water Heater Thermostats
Replace the thermostat on an agas water heater since it is not as simple as it may appear. For starters, the thermostat on a gas unit is a part of the gas control valve, rather than being separate. Consequently, if the thermostat is not functioning correctly, you would need to replace the entire gas valve. Despite the fact that you might be able to accomplish it if you have prior experience, we strongly advise against it. Working with a number of different gas connections is required while changing the gas control valve.
As a result, we recommend that you call a heating contractor or a plumber in your area.
Furthermore, in certain situations, a malfunctioning gas valve is so expensive that you may use it as a warranty for a completely new machine. This is especially true if the equipment is nearing the end of its warranty period or has suffered significant damage.
Not a Faulty Thermostat?
If your water is suddenly overheating and you know it isn’t due to the thermostat, check your water pressure and temperature. One of the most prevalent causes of scorching hot water is water that has a high concentration of minerals. If you reside in a region where the inlet water is hard, this is something you should certainly look into. Hard water is defined as groundwater that has a high concentration of minerals such as magnesium and calcium. These minerals gravitate toward the heating components, where they eventually produce corrosion and a crust.
They gradually become more demanding, finally overheating and succumbing to exhaustion (2).
Fortunately, changing the heating components and flushing your device on a regular basis can correct the problem.
Get It Done
Replace a water heater thermostat if you have an electric one because it is reasonably simple to do. Simply turn off the power, detach the wires, and carefully remove the thermostat before replacing and reconnecting them. If you have a gas unit, on the other hand, you should consult with an expert since working with gas is extremely dangerous and there is no room for error. If you’re replacing your electric thermostat, make sure you get one that’s exactly like it. Nonetheless, if your intake water is very hard, be sure to inspect the heating components.
Are you eager to put your skills to the test and replace your thermostat?
Alternatively, if you have any further questions or remarks, please post them in the comments section below.
Electric Water Heater Thermostat Replacement Guide
Replace the thermostat on your electric water heater by following the step-by-step instructions provided below. Thermostats for domestic water heaters are almost universally interchangeable. A single element water heater thermostat, on the other hand, will not function on a double element water heater.
Replacing an Electric Water Heater Thermostat
Turn off the electricity to the water heater. The access panel, insulation, and plastic safety cover should all be taken off. Check with your multimeter to ensure that the electricity is turned off. The top thermostat on aduel element home water heater is seen in the photo on the left side of this page. The thermostat for the hot water heater is kept tightly against the tank by a racket constructed of spring steel. To remove the thermostat, use a screwdriver to pull one side of the bracket out just far enough to release the thermostat from the bracket.
- Pull thethermostat out of the bracket by prying it out of the opposite side of the bracket.
- If either side of the bracket is wrenched out too much, the thermostat will not be held tightly against the tank any more (very important).
- This may be sufficient to return it to its original position and maintain the thermostat.
- Screwdriver the lock clips up (bottom of image), then take the bracket off.
- It will be held in place by the lockclips.
- It should be positioned tightly against the tank.
- The thermostat for the lower electric water heater is replaced in the same manner.
- If you have a single element water heater, make sure you get a thermostat.
Activate the power source. Top thermostats are sometimes referred to as higher or principal thermostats in some circles. Lower thermostats, sometimes known as secondary thermostats, are located at the bottom of the thermostat.
Related pages
Turn off the electricity to the water heater. In order to do this operation you must first remove the accesspanel, insulation, and plastic safety cover. Make sure the power is turned off using your multimeter. The top thermostat on aduel element domestic water heater is seen in the photo on the left side of the screen. By using a spring steel racket, it is possible to keep the hot water heater thermostat securely attached to the tank. To remove the thermostat, use a screwdriver to pull one side of the bracket out just far enough to release the thermostat from its mounting.
Pull thethermostat out by prying it out from the other side of the bracket.
Even if one or both sides of the bracket are pryed out too much, the thermostat will not be held tightly against the tank (very important).
As a result, the thermostat may be held in place for a longer period of time.
Pry the lock clips up (at the bottom of the photo) using a screwdriver, and then take the bracket out.
It will be secured in place by the lockclips.
It should be pressed up against the tank tightly.
This method is also used to replace the lower electric water heater thermostat.
For a single element water heater, be sure you get a thermostat.
Activate the electricity.
Lower thermostats, sometimes known as secondary thermostats, are located at the bottom of a thermostat’s housing.