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.
Step 2
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.
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
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.
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
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.
- 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.
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.
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.
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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.
You should call a local specialist if you are experiencing problems with your water heater in the Sacramento region to decide whether it needs to be replaced or repaired.
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 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
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:
- Turn off the electricity to the water heater
- Remove the access panels and insulation to gain access to the thermostats and heating/cooling elements. By rotating the dial in the middle of the higher thermostat to high and the lower thermostat to low using a screwdriver, you may set the top thermostat to high and the lower thermostat to low. For greater temperatures, turn the knob clockwise
- For lower temperatures, turn the knob counterclockwise
- Restore power to the system
- Check the wires above the reset button on the thermostat with a multimeter (we recommend theUEI UTL33T digital multimeter) to ensure that they are reading 240v. Inspect the higher element for power by checking the terminal screws on the upper element. If there is no electricity, it is necessary to replace this thermostat. If you do discover that there is electricity, then check the lower thermostat setting. Set the lower thermostat to high while keeping the upper thermostat at low temperature. As before, check certain that there is voltage, this time to the bottom element.
- If there is electricity and the water begins to heat up, the lower thermostat is most likely in excellent working order. When you lower the temperature of your water heater, you should hear a clicking sound. That’s the sound of your thermostat turning on. If there is no voltage, then check the lower thermostat by putting one probe of the multimeter to the top contact screw and the other probe to the metal of the tank. If there is no voltage, then check the upper thermostat. Unless you receive a reading, you will need to have the higher thermostat repaired or replaced. If you obtain 120 volts, you know that the higher thermostat is working properly. Remove the probe from the top contact screw and touch it to the bottom contact screw while still contacting the tank with the other probe. Repeat this process with the other probe. If you only receive 120v, that’s ok. If you receive nothing, it is necessary to replace it.
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 additional information on water heaters, please refer to our help resources or thisWiki article on the subject.
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
The first step is to switch off the power to the water heater. By flipping the breaker to the “Off” position at the breaker box, you may complete this task.
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
The thermostats are held in place by specific brackets that ensure that they remain in close contact with the tank at all times. This is done in order for them to be able to detect the temperature of the water. Make use of the screwdriver’s shaft to gently but firmly push out one side at a time, starting with the left side. To remove the bracket, pry one side of it apart while carefully twisting the thermostat upward. If you do this, the bracket will not be able to lock. Don’t be concerned if you break the bracket by mistake; it will be replaced.
5.Disconnect the Wires
Disconnect the wires one by one, starting with the ground. When you are through with one wire, apply a little piece of colorful tape or a band-aid to the wire and the terminal it is connected to. Each wire and terminal set should be labeled with a different color. When you’re finished, you’ll be able to easily reinstall them in the proper location.
6.Remove the Thermostat
This is arguably the most difficult portion, and you should proceed with caution. To begin, unscrew the screw terminals that are holding the thermostat in place using a screwdriver. Each wire should be disconnected from its termination. When you look at the thermostat, you’ll notice that it is held in place by retaining clips. Remove it from the clamps with care, and set it to the side for now. Keep an eye out for danger. Make sure you are careful because if the clips break or bend, you may not be able to repair or replace them.
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?
Thermostats for electric water heaters are very straightforward equipment. They operate on the basis of a bi-metal switch located at the rear of the thermostat, which detects the temperature of the water tank. When the temperature of the water inside the tank reaches the desired level, the bi-metal switch is activated or deactivated. This either connects or disconnects the unit in order to prevent the water from overheating while in use. Normal temperature adjustments are accompanied by a clicking sound, which is caused by the metal switch altering the temperature.
- If you are unable to locate a thermostat that is comparable to the previous one, count the number of components in your device and the voltage they operate at before searching for a replacement.
- If all else fails, the majority of domestic water heaters operate at 240 volts.
- The right side of the thermostats used in single-element water heaters has just two screws, which are on the left side.
- It is possible that a dual element thermostat will still function on a single element tank.
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.
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). This will also cause the water within the tank to become too hot to drink. 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.
How to Test, Troubleshoot & Repair an Electric Water Heater Thermostat: DIY Guide
Every year in the United States, around 1.5 million water heaters are replaced. That’s a significant amount of money. However, not all water heater issues are severe enough to warrant the purchase of a new heater. Some electric water heater thermostat problems might be resolved by doing a DIY repair at home. And that is exactly what this tutorial is all about. Let’s have a look at how to test and repair an electric water heaterthermostat now, shall we? Before we go any further, what exactly is the purpose of an electric water heater thermostat, and how does it function?
What Is The Purpose of an Electric Water Heater Thermostat?
We wash our clothes, do the dishes, and take a nice shower every day. However, the amount of hot water we consume for these tasks is not the same. Furthermore, the thermostat is essential since it regulates the temperature of the electric heater. An electric water heater is, at its most basic level, a piece of electrical equipment that consists of three components: a heating element, a thermostat, and a switch. Electric water heaters are used to heat water for various purposes. As a result, the thermostat functions as a switch that is actuated when the temperature of the water changes.
- When it senses a drop in water temperature, it will activate the elements, causing them to generate heat.
- So, how does it determine if the water is cold or hot to drink?
- Furthermore, there is no insulator at the point where the tank meets the thermostat.
- Having stated that, when electricity is introduced into the device, the heating element becomes extremely hot and begins to convert the power into heat.
This then transforms your cold water into hot water, at a temperature of around 120°F. Finally, the high limit switch keeps the hot water from becoming scorching hot while it is running.
How Does An Electric Water Heater Thermostat Work?
Electric water heaters are classified into two categories:
- In addition to the single element water heater, there is also a twin element water heater.
The single element type is comprised of a single element thermostat as well as a single element heating element. Tanks are often lower in size since only a single thermostat is required to regulate the temperature. Two thermostats and two heating elements are found in the dual element water heater, on the other hand. The majority of water heaters are dual-element water heaters, which is what we’ll be focusing on throughout the remainder of this article. A single element heater, on the other hand, may be checked and changed in the same manner.
- The thermostats for electric water heaters generate heat in the tank by enabling energy to flow into the elements of the water heater.
- The top thermostat, which is also the principal thermostat, regulates the heating element in the top part of the unit, as well as having a high limit switch.
- Keep in mind that the high limit switch, which is placed in the same region as the higher thermostat, includes a reset button that activates when the water temperature becomes too warm (over 170F).
- A 240-volt power supply is used to heat the water, which is subsequently heated by the higher heating element.
- The problem is that only the water in the upper part of the tub becomes heated, while the water in the lower half is either chilly or lukewarm at best.
- As the bottom heating element gets 240 V, it warms the water in the bottom region to the temperature that has been specified before the process is completed and turned off.
Problems with Electric Water Heaters
Sometimes, when your heating elements or water heater thermostats fail, you will notice a difference in the performance of your device. If the upper element or thermostat in your water heater breaks, the water heater may be unable to provide hot water. And whether it’s the bottom element or the thermostat that’s defective, you’ll find that you’re running out of hot water quite soon as well. These, on the other hand, might be a result of the cold weather or pipes that are not properly insulated.
However, it is possible that this is due to the thermostat being set too high or the changing of the seasons.
A defective electric water heater may also take an excessive amount of time to reheat the water in your water heater. Other issues might arise as a result of improper tank maintenance or excessive water pressure at home.
How to Test an Electric Hot Water Heater Thermostat and Fix it: Step by Step Guide
We’re going to test both the thermostats and the heating components in our unit to be certain that we’re not dealing with a false alarm. It’s important to note that if your elements are open and grounded, the algorithm may produce a misleading result, which is why we’re also evaluating them. It is necessary to have a Flathead and Philips screwdriver, as well as a digital multimeter, in order to carry out the test described in this section. Let’s get this party started.
Step 1: Turn the power source off
Locate the water heater breaker panel on your circuit breaker panel and switch off the water heater or the hot water supply.
Step 2: Remove the outer access panels
With a flathead screwdriver or 1/4-inch nut driver, pry up the top and lower thermostat access panels on the unit’s left and right sides.
Step 3: Remove the insulation
You have two options for removing the insulation: either entirely remove it or fold it over the thermostat. As well as removing the plastic safety barrier that was covering the thermostat and heating element, Also, use tape to hold the insulator in place as you work on this step, and be careful not to yank the wiring out as you work.
Step 4: Check the high limit switch button
Check to see whether the red high limit reset button has been triggered by accident. If it has, you should push it. The red switch button may trip on occasion if the heating components fail, if the connections on the thermostat have fused closed, or if the thermostat is not calibrated properly.
Step 5: Disconnect the wires
Using your Philips screwdriver, disconnect the wires that are entering each terminal on your computer.
Step 6: Turn the temperature setting to the highest
Make sure that the temperature on the top thermostat is set to its maximum level, and that the scale on your multimeter is set to RX1.
Step 7: Check the thermostat and heating element with a multimeter
Set the resistance of your analog or digital meter to the lowest possible value, which should be 200 ohms. You should hear a click sound at this point. Then attach the black probe to the screw terminal on the left side of the screw terminal. In addition, connect the second red probe to the other terminal, which is still on the left side of the board. Then, using your reading, check to see if the thermostat is still operational. As long as the meter shows zero or a reading that is very near to zero, your thermostat is in proper operating order.
Credits:
Step 8: Repeat the process for the right side
In addition, lower the top thermostat on the right side to its lowest setting and connect the probes to the screw terminals on the left side. This should also return a zero as a result of the condition.
Step 9: Take the meter reading on the lower thermostat
After confirming that the upper thermostat is in proper operating order, repeat the process to ensure that the lower thermostat is in proper working order. Take note that there are only two connections on the bottom thermostat, which is a little number. Check to ensure that the reading is zero before continuing. Assuming that the thermostats are in good working order, you may check the heating components to make sure they are working properly. However, if one or more of the thermostats needs to be replaced, continue reading.
How to Replace A Faulty Thermostat on an Electric Water Heater
It is rather simple to replace a malfunctioning thermostat. Furthermore, purchasing a new one is inexpensive. As a result, even if the problem is with a single thermostat, we’re going to replace both of the thermostats.
Prior to doing so, you’ll need to make sure that all of your thermostats are from the same brand. If you are unable to obtain this product, another one from a reputable brand would suffice. You’ll need a few tools.
- A flathead screwdriver, a Philips screwdriver, a digital multimeter or a voltmeter, and a replacement thermostat are all necessary tools.
Now it’s time to get started.
Step 1: Turn off the power supply to the heater
You don’t want to be working with the electricity turned on. So go to the circuit breaker panel and turn off the electricity to the water heater that is currently attached to it.
Step 2: Remove the outer access panel and insulation
Electric water heaters feature access panels on the outside that protect the thermostat and heating components. Remove the insulating pad and plastic covering by unscrewing the nut, taking care not to contact the wires in the process.
Step 3: Take out the Thermostat
Take a photo of the wiring before you remove the malfunctioning old thermostat so that you can remember which wire goes into which terminal while you’re attaching the new thermostat. Alternatively, you can label the wire. Using your multimeter, you should also check to see if it is turned off. Then, using a Philips screwdriver, remove the screw terminals and separate the wire from the terminals. After that, you may peel the thermostat away from its attachment clamps and bracket. However, proceed with caution so as not to harm the clips.
Step 4: Install the new thermostat
After you’ve successfully removed the broken thermostat from the water heater, you’ll need to fix the new thermostat installed in the water heater. Position it appropriately so that it rests comfortably on the surface of the storage tank, and attach the appropriate clips by referring to the image you captured in the preceding step. In addition, connect the circuit wires to their corresponding screw terminals and tighten the screws on the terminals. In addition, it may be a good idea to examine the heating components, clean them, and replace them.
Step 5: Set the temperature of your new thermostat
When you’re certain that the wires are correctly connected and you’re through setting up your thermostat, use your flathead screwdriver to adjust the temperature to the ideal setting for you. The optimal temperature is 120 degrees Fahrenheit.
Step 6: Replace every other thing you took out
Having completed your setup, it is now time to reinstall your insulators as well as the chamber access panel. After that, reconnect the power supply by turning on the water heater breaker on the circuit breaker panel to the water heater.
Step 7: Cycle test your electric water heater
If you want to test if your water heater heated your water sufficiently, you may turn on the hot water faucet for two hours and observe if the heater did a good job. Troubleshooting Other Water Heater Issues and How to Resolve Them Leaks of water: The majority of the time, faulty valves and plumbing connections are to blame for water leaks in the home. However, corrosion in the water heater tank or loose components in the water heater tank might be the source of the problem. If your tank has rusted beyond repair, you will have no choice except to replace it.
- Noises coming from the tank: If your tank is making noises such as rumbling, popping, or high-pitched sounds, it might be due to boiling water.
- Things’s a simple matter of putting it back together.
- If it does not function, the tank should be replaced.
- It’s also possible that the corrosion is occurring in your pipes.
- If the water flowing through your home smells like rotten eggs, it’s possible that bacteria has accumulated in your hot water tank over time.
It is possible that you may need to replace the anode rod in order to correct this. You, on the other hand, cannot achieve this on your own. In addition, hire the services of a skilled plumber to help you.
Wrapping up
You should now be aware of the measures to take in order to simply test and replace your faulty water heater thermostat. Working with electricity, on the other hand, may be quite dangerous, therefore take steps to ensure that the power supply to your water heater is always turned off. Another thing to keep in mind is that silt that accumulates at the bottom of water heater tanks is the most significant factor in lowering the performance of water heaters over time. It might also lead to the overheating of your heater.
Other options include installing a sediment filter and/or a water softener in your water supply.