Informational Guide

Water Heater Keeps Turning Off?

Whatever water heater you own, if you find yourself wondering, “why does my water heater keep turning off,” then read this complete guide!

by Josh Mitchell

Have you ever found yourself waiting at the faucet or shower for warm water just to realize it's not coming?  

Luckily, many of these problems can be addressed quickly; therefore, you don't have to pay a professional plumber for repairs. However, some issues require calling a professional as doing it yourself may put you in danger or damage your water heater 

Whether it's an electric water heater, tankless water heater, or gas water heater, if you find yourself wondering, "why does my water heater keep turning off," then read on! 

Most households in the US have electric water heaters, primarily because they don't break down as frequently as gas water heaters. However, malfunctions may still occur.  

So, if your water heater shuts off suddenly, here are a few things you should know that may come in handy. All electric heaters share a similar system that is composed of the following parts:  

  • Thermostat 
  • Heating element 
  • An electrical receptacle 

Any of the above parts of your electric water heater can break down, causing it to turn off repeatedly. Here are a few symptoms of faulty electric water heaters and how you can fix them: 

Problem 1: Faulty Electric Supply 

The electrical receptacle is the central part of your unit's electrical system. It's what directs the power towards the device.  

So, if your unit keeps tripping, chances are the problem lies with the electric supply. And bear in mind even a broken wall socket can be a severe issue. 

How To Fix  

If there's a cracking or a buzzing sound as you turn on the water heater, shut it off right away. This is primarily to prevent an explosion or a short circuit.  

Next, call a professional electrician as this can cause serious damage.    

Problem 2: Bad Thermostat 

A thermostat manages both the lower and upper heating elements of your water heater. As the water gets cold, it signals back to heating elements, causing water to reheat.  

Moreover, if you've got a hybrid or HVAC system, you'll see similarities with the thermostat on an AC unit. 

Most electric heaters come with two thermostats — lower and upper. That's because the unit has two pilot lights (heating elements), and both need a thermostat.  

How To Fix 

  • Find the lower and upper thermostats (look at manual if need be) 
  • Ensure that they're both connected to power 
  • Look for the reset button and press it to ascertain if it works 
  • If the upper thermostat doesn't show power reception, replace the thermostat 
  • However, if it shows power reception but doesn't provide warm water, you have to buy a new heating element 

Problem 3: Heating Element Malfunction 

Heating elements are what warms the water when the thermostat requires it. Unfortunately, it's among the most common causes of a heater that keeps shutting off.   

If there's a heating element malfunction, chances are you won't get warm water. This is because if the heat source is down, the tank water will remain cold, even if everything else keeps operating.  

How To Fix 

Call a plumber to change the heating elements and avoid doing it yourself, mainly because it may cause an electrical short circuit if it's placed incorrectly.  

Problem 4: Bad Reset Button 

If the reset button of your unit keeps tripping, there's a good chance the fault lies with internal circuitry. The reset key on electric water heaters is designed to cut electricity to the unit if the temperature surpasses 180°F.  

However, with daily use, the switch can wear down, making it difficult for you to read the temperature of the water accurately.  

When it happens, the reset key switch may cut electricity to the device even though the water temperature is extremely low.  

How To Fix

With wear-downs, there is no other solution than to replace the reset button. This is a common request and can be quickly looked at by a professional. 

Problem 5: Bad Wiring Or Breaker 

Your problem might be electrical such as bad wiring. As a result, it may pose a severe safety hazard. Luckily, the heater is well-equipped to counter any electrical accident.  

When you have a loose wire, excessive heat is generated. Since the reset key can sense this excess heat, it trips automatically.  

Other wiring problems can arise if you've copper wiring (in the water heater) and aluminum wiring (in the house).  

How To Fix

In such a case, a lug compression connector needs to be positioned precisely where the wires meet.   

Without an appropriate lug connector, the two different metal connections may cause the breaker to trip. Another possibility is that your home's internal breaker has worn out, causing the reset key to trip.  

water heater leak

Tankless Water Heater Keeps Shutting Off: Common Causes & Fixes 

Tankless heaters are arguably one of the best investments you can make for your office or home.  

Not only are they highly efficient, but they also help you save money by warming water on-demand. But like any other appliance, a tankless heater also faces many issues.  

So, here are some potential reasons why your tankless heater keeps tripping:  

Problem 1: Mineral Build-Up 

Whether you use tankless water heaters or other conventional options, you should always track any potential mineral build-up in the system.  

This is because hard water, unlike soft water, contains an extremely high amount of minerals. 

Hence, the harder the water, the more chances for mineral build-up! 

Magnesium and calcium are two of the most common minerals that lead to scaly build-up, which in turn can negatively affect the performance of tankless water heaters.  

Why Does My Water Heater Keep Turning Off

How To Fix

Here is how you can descale mineral build up in your tankless water heater: 

  • Switch off and disconnect the device 
  • Shut off cold water valves 
  • Block the valve that connects the device to the house 
  • Leak the internal pressure by opening the purge valve 
  • Connect the correct hose lines 
  • Reopen the purge 
  • Run natural (non-synthetic) vinegar through the heater 
  • Next, run warm water through the system and drain it all 
  • Shut the purge 
  • Remove the hose lines 
  • Reinstall the device to the home water lines 
  • Switch it on 

Problem 2: No Ignition And Flame Failure Message 

Ignition issues can be a hassle. Based on the water heater model, it must show a message that reads "no ignition." There can be many reasons for this, such as: 

  • Inadequate gas supply 
  • Blocked water or gas valves   

Moreover, the flame failure message is quite similar to the ignition problem. Some causes that may lead to flame failure problems include: 

  • Small or narrow gas lines, unable to create a steady flame 
  • Inadequate ventilation 
  • Regulator failures

How To Fix

Here is how you can fix this issue: 

  • Shut off the device 
  • Attempt to restart it 
  • Now, try to function it normally 

If it begins heating again, the problem can be attributed to the switch, and you should get a professional to replace it. 

Problem 3: System Overload  

Another common reason for tankless water heater's to shut off is system overloading.  

Your heater comes with a particular capacity and size. And if you're heating a significant amount of water than required, you're overloading the entire system.  

Still wondering how?  

You can burden the heater if you're opening multiple warm water faucets or operating several warm water systems simultaneously. Moreover, overloading of the unit is damaging because: 

  • You won't have enough warm water 
  • The unit can overheat and overwork  
  • The unit can turn off 

How To Fix

Unfortunately, there are no inexpensive fixes for this, especially if the overload capacity is your general daily requirement. Therefore, consider these options: 

  • Conserve simultaneous water usage 
  • Buy one more water heater 
  • Enhance the heater's capacity 

Problem 4: Minimum Flow Rate 

The minimum flow rate details the amount of water required for a tankless heater to work correctly; in other terms, to achieve the "heating signal." 

This issue occurs when you've got an old-school tankless heater merged with the newly installed eco-friendly showerhead.  

The showerheads are excellent for the environment and water-saving; however, they won't use sufficient water to fire the tankless heater up.  

So, as a precautionary measure, tankless heaters turn off when they don't have enough water.  

How To Fix

There is no fix for this per se; however, there are things you can do to maintain an adequate water flow: 

  • Consider home occupancy and usage before purchasing 
  • Consider flow rate permitted by the tank inlet 
  • Consider the peak flow rate 

Gas Hot Water Heater Keeps Turning Off: Main Reasons & Fixes 

Compared to tankless and electric water heaters, gas heaters are new; however, they've become increasingly popular over the past few years.  

That's because these tankless gas heaters are affordable and energy-efficient. Nevertheless, here are some common reasons for gas heater malfunctions: 

Problem 1: The Pilot Burner Is In Bad Shape 

One of the more fragile parts of any gas heater is the pilot light. And there's a strong chance that the problem of tripping rests with its dirty pilot burner.  

Here's how it happens: When there's dirt or dust on a pilot light, it will shut off, which as a result, will halt the entire gas heater. That's because dust/dirt will obstruct airflow.   

How To Fix

Since the cleanup process isn't too straightforward, it's best to call the plumber and let them do the cleaning.  

And even though you can rekindle the pilot light on your own, the problem will reappear. And ultimately, it may cause your entire gas heater to malfunction, leaving you with additional expenses.  

Problem 2: Faulty Thermopile 

A thermopile is a component that reacts to the pilot burner and starts producing gas. Just as the pilot burner, a thermopile can malfunction as well if it's dirty or worn out.   

If the thermopile can't signal appropriately, the gas heater won't operate, even though the pilot burner is working.  

How To Fix 

Fortunately, it can be replaced easily, and a replacement thermopile is comparatively inexpensive. But as was the case with the dirty pilot burner, it's best to call your plumber to perform this task.  

Problem 3: Dirty Or Clogged Air Inlet 

The air inlet is also a crucial part of a gas heater, and like the last two, it is also sensitive to dust and dirt. Its primary responsibility is to ensure that the air flows to the prime burners.  

If it's clogged or dirty, oxygen won't reach the light, and it will shut off.  

How To Fix

The perfect way to avoid this problem once and for all is by having your gas heater checked and maintained regularly.  

If it gets clogged or dirty, the plumber can wash it without any hassle. Or better yet, you can attempt to do this on your own. 

Problem 4: Blocked Gas Supply 

Another possible reason why your water heater keeps shutting off is the blocked gas supplyAn uninterrupted gas flow to a pilot burner is essential for gas heaters to work effectively and properly.

However, if the gas supply is blocked entirely or the amount reaching is inadequate, the pilot burner will turn off.  

How To Fix

Ensure the gas valves don't have any blockages within them. It's the only viable method to make sure that the gas reaches the pilot burner.  

reliance water heater parts

People Also Ask (FAQs)

Why does my rheem water heater keep shutting off?  

If your Rheem water heater continually shuts off, chances are the thermocouple is damaged, bent, or dirty. So, check the thermocouple, and in case it's damaged, change it. However, if it's dirty, just wash it up. 

Do all hot water heaters have a reset button?  

Yes, all water heaters come with reset buttons; you just have to pat around the device to find it. It's usually a bright red color and is often placed around the thermostat. Moreover, it can also be found hidden behind a detachable metal panel or insulation.  

Is it dangerous if the pilot light goes out on the water heater? 

In many instances, this situation doesn't represent a significant risk. That's because contemporary gas water heaters come with valves that naturally close the gas supply when a pilot burner goes out.  

What is the average cost to repair a water heater that keeps shutting off? 

The repair of water heaters that keep shutting off will cost you anywhere around $355 to $1750. Therefore, the average repair cost will be approximately $655.

However, the repair cost of water heaters varies based on several factors, such as your unit's age, type, warranty, and the contractor you choose.   


Whether you've got a tankless water heater, electric water heater, or gas water heater, all are vulnerable to wear and tear.  

There are many reasons why your water heater keeps shutting off, and if you face any of the ones we have mentioned, use this guide and fix the problem! 

Josh enjoys researching, testing and diving into home improvement & DIY products. He has a passion for tools, learning new skills and fixing the everyday problems that arise around the house.