Water Leaking from Thermostat on Wall? -Let’s Fix the Issue!

There is nothing more frustrating than seeing a puddle of water around your thermostat or soaking wet walls around it. The thermostat was not supposed to ‘leak’ at all!

So, why do you have water leaking from thermostat on wall?

Water leakage is most commonly seen in the water heater thermostats. A cracked or damaged rubber gasket that seals the opening of the heating element can be the cause. As it ends up the heating element as well which leads to the water leak. And failing to apply accurate temperature settings on the thermostat can cause the water to leak on the wall.

That was just the preview of the whole thing. If you want more info on this matter, keep reading this article.

Water Leaking from Thermostat on Wall: 2 of the Most Common Reasons and Solutions

why is water leaking from my wall
Source: riskplumbing.com

Along with providing many functions to make your life a bit easier, thermostats can cause you trouble with certain issues. For example, issues like flame icon blinking, fan delay or the water leaking issue.

The problem of water leaking from the thermostat on the wall is most often seen in water heaters. There can be many causes for why it happens. Here I have included the possible reasons and provided their solutions as well.

Reason Solution
Cracked or damaged gasketReplacing the heating element
Inaccurate temperature settingTurn down the heater’s thermostat

Reason 1: Cracked or Damaged Rubber Gasket

Many users complain about water leaking just below their thermostat. When observed, it actually seems like the water is leaking from the thermostat. 

However, it’s not actually the case because a thermostat on any water heater never leaks. The water that is dribbling out of your thermostat is most probably from the heating element. 

The heating element is sealed at the tank opening using a rubber gasket. If, by any chance, the rubber gasket breaks, cracks, or gets damaged, the water would start leaking from that place. And it ends up drenching the thermostat area which many people mistake as thermostat leaking.

Solution: Repair Gasket or Replace the Heating Element

When the rubber gasket of a heating element gets damaged or cracked, the heating elements can break or become misshapen as well. You can call an expert to get it repaired.

However, most heating elements cannot be fixed, so getting them replaced is the only way. Here are steps for how to replace the heating element to stop water leaking. 

Step 1: Turn Off the Power

First of all, find the circuit breaker in the main electrical panel. Then turn it off. In case you use fuses, remove them. Now inspect the hot water faucet and see whether the water is cool enough. If yes, move on to the next step.

Step 2: Access the Heating Element

Pull out the access cover panel that you will find on the water heater. Now, move the insulation from your element. It will expose the circuit wires and the screw terminals.

With a circuit tester, test if there is any power flow to the wires. If not, take out the screws and also disconnect those wires.

Step 3: Drain the Water Heater

Now you need to turn off the line that provides cool water to your heater. Attaching the hose, drain it. Then put the hose over the floor drain and just drain the water from the water heater. Keep draining til the water line goes below the element.

Step 4: Remove the Heating Element

Water heaters usually have two types of heating elements. So, your heater can have a screw-in heating element or it can have a flange-type heating element. 

For the screw-in elements, grab a socket wrench that has a 1 ½-inch socket. Then turn the element counterclockwise. 

For the flange-type element, take out the screws and gasket first and then remove them from the water heater.

Step 5: Installation of New Heating Element

Confer your instruction manual for the appropriate heating element. By doing this, you are also ensuring that you have the accurate voltage and wattage.

Before installing the element, thoroughly clean where the rubber gasket conforms to the tank. Place the gasket over your new heating element and then place it in the tank.

If yours is a screw-in element, use a socket wrench and turn it clockwise. If it is a flange-type element, the process is to screw in the mounting screws.

Step 6: Refill Water Heater

After installation, close your heater’s drain and refill the water heater. Now run the hot water faucet for about 3-4 minutes as the water starts flowing.

Step 7: Reconnect Wires

Finally, hold the black and white wires, and wrap these around your screw terminals. Do it in a clockwise pattern. Make sure to wrap them nicely and tightly. Then go ahead and start reassembling that cover plate. 

Now you can turn the power back on to run your water heater. And the water should not leak this time.

Reason 2: Inaccurate Temperature Setting

Another reason for thermostat leaking can be the thermostat’s inaccurate temperature setting. Most possibly, it is set too high.

Because that is when the temperature as well as the pressure relief valve automatically opens and starts discharging water. And it results in a leak in the thermostat. 


You can try and turn down your heater’s thermostat. It will lessen the temperature. 

According to OSHA, the ideal temperature is 140° Fahrenheit. 

And the CPSC recommends a thermostat setting of 120° Fahrenheit.

So, setting your thermostat to 130° Fahrenheit would provide you with the most sufficient results. It would be the best choice. 

However, If the leak still persists or you notice water dripping shortly after turning it back on, you need professional help. Consider calling a plumber to get the thermostat issue fixed.

What Are the Risks of Having a Leaking Thermostat?

A leaking thermostat can be dangerous and can have many risk factors.

So, if you leave your leaking thermostat untreated, it can lead to various potential damages. Here I have discussed a few.

Fire Hazard Due to Malfunctioning Pressure Valve:

If the thermostat is leaking, that means your pressure valve is not functioning well. This can also mean that other parts are also not working properly. And this can lead to a disastrous fire hazard. 

Risk of Getting Burned:

Another risk that comes without saying is the scalding risk. The main job of a water heater is to heat the water. So, when you see water leaking from the thermostat housing, there are chances that it may leak scalding hot water. Thus, it is a better idea to be careful when dealing with these leaks to avoid getting burned.

Leaking Thermostat can Cause Overheating:

Now you may also wonder: can a leaking thermostat housing cause overheating?

Well, the answer is yes, it can overheat if the thermostat housing continuously keeps leaking. Because it is the thermostat that controls the coolant flow through the engine and radiator. Hence, it is better if you get the issue fixed right away.

Repairing Cost is High:

Well, thermostat housing leak repair cost can range between $180 to $420 including the parts and labor cost. Which is close to a smart thermostat installation cost. But it is worth every penny to get the leakage issue fixed to avoid any unwanted disaster.

Frequently Asked Questions (FAQs): 

How long do thermostats last?

The regular modern home thermostats will last about 10 years. However, thermostats usually become outdated and replaced sooner as there are new innovations in the market. For example, non-programmable ones are now becoming outdated and being replaced by programmable ones.

What happens when a water heater thermostat goes out?

The main job of a thermostat is controlling the heating element that heats the water. So, as the water attains a certain temperature, the thermostat shuts the element off. So, when a thermostat goes bad, it will cause the heating element to operate continually. As a result, it will end up overheating the water.

What causes a thermostat to fail?

The main reason for a thermostat failure can be contaminated fluid. Or if the thermostat has gone old with weakened springs, it can fail. Fluid contamination usually occurs if discordant coolants are mixed. Also, if you have neglected to change the old coolant or the particulate matter from the gaskets breaks off, the thermostat can fail. 

Wrapping Up 

Hopefully now you have a sound idea about water leaking from thermostat on wall

For any confusion, you have this guide handy. You can fix thermostat leaking issues following the steps I provided.

One more tip before you go, try to keep an eye on your thermostat and check it at least once a week to see if there is any leakage. By doing this, you can save yourself any unwanted damage.
That was it as of now. Have a great day.

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