Should I Turn Off Water Heater If Water Is Off?

Water heaters are a significant appliance that supplies hot water for every necessity in the home. But there is no need for the heater to function when you are on vacation or when there is a water outage. Should you turn it off or leave it turned on? Let’s discuss this in detail.  

Generally, If the water is off for a short duration (say a few hours), you do not need to turn off your water heater. However, if the water is off for a longer period, then turning off the heater will protect it from the damage of excessive heat buildup as the water tank is empty.

In this article, you will know when to turn off and how to protect your water heater during a water outage. So, keep reading. 

How does the water heater work? 

There are two common types of water heaters. 

Tankless heaters and those that use a tank. 

Due to this difference, the configuration of the heater differs. 

These two common heaters use gas or electricity to heat the water in the tank. 

The main components of heaters that use tanks involve the tank, heater, inlet water supply, and outlet water supply lines. 

A water heater with a tank contains three pipes. 

The first is to carry cold water from the tank to the heater. 

The second one is to carry the hot water out of the heater. 

And the third one is a safety valve near the tank to control the water pressure released from the tank. 

A water tank contains cold water in it. Whenever there is a need for hot water, cold water travels through the pipe to fill the water heater. 

A water heater fills the cold water and begins heating. 

It is coated with a corrosion-resistant cover to protect the inner lining of the water heater from damage. 

As soon as the water starts filling in the heater, a heating element located at the bottom will be activated and raises the heated water above the heater to be carried by the hot water pipe whenever there is a demand for hot water in your home. 

Suppose the water heater continues to run even during the water outage. 

In that case, the inner lining of the heater will be damaged. 

When the hot water is not used, it will stay at the bottom of the heater and continue to heat. 

Let’s see how tankless water heaters work. 

Tankless water hearts are gaining popularity as they are more energy efficient than a standard water heater. 

As tankless water heaters don’t want to keep running to keep the water hot, the energy consumption is low. 

Tankless water heaters are of two types. Boiler-mounted and standalone water heaters. 

Tankless water heaters work by heating a coil to boil cold water when there is a demand for hot water. 

Boiler-mounted water heaters use boilers to produce heat to turn cold water into hot water. 

At the same time, standalone water heaters use a coil, heat exchanger, and gas to heat the water. 

Tankless water heaters have low flow compared to standard water heaters. 

In the case of using a tankless water heater, turning it on won’t cause serious issues. 

However, when you are away from the house for a long time, turning off all the electrical appliances is best.  

Also read: Why Is My Hot Water Tank Constantly Filling?

Why Turning Off Your Water Heater Matters?

I have a real incident regarding the importance of turning off the water heater during a water outage. 

I went on a two-month-long vacation a year ago, leaving the house completely dormant. 

I left the water heart turned on even after turning off the water supply. 

Even after turning off the water supply, there was still water standing in the water heater as I didn’t drain the water. 

It was being heated continuously without being used. It seems that it kept expanding, creating pressure on pipes. 

At some point, due to the persistent pressure, pipes, and valves burst. 

When I returned, it was such a shock to me. 

I hired a professional to repair the damage. 

It was such an expensive repair as I had to pay the professionals and buy damaged parts. 

So, turning off the water heater is important, especially if you have a water heater using a tank. 

Sometimes, when you leave the water heater turning on when it is completely dry, it damages the inner lining of the heater. 

It reduces the heating efficiency of the water heater. 

In the long run, you will have to replace the unit completely. 

The Pros and Cons of Turning Off Your Water Heater During Water Outages

Before turning off the water heater, you must know its pros and cons. Here are the pros and cons of turning off the water heater: 

Pros of turning off the water heater

• Turning off the water heater when not using it will save you more energy. If there is a water outage in your locality or you are going on a vacation, turning off the water heater will save electricity or gas bills. 
• If you turn off the water supply or there is a water outage in your locality, turning off the water heater will prevent internal damage. When the water heater continues to work without the water supply, its heating element will be damaged. It will also cause overheating in the water heater. 
• Turning off the water heater will ensure safety from electric hazards when not at home. 

Cons of turning off the water heater

• Suppose you have turned off the water heater while on a long vacation; you will not get hot water immediately when you return home. After you turn it on, it will take time for the water heater to supply hot water. 
• There is a risk of bacterial and mold growth while keeping the water heater turned off for a long time. The water tank of the heater will be wet, and heat will not be produced as the heater will be switched off. This forms a suitable environment for bacterial and mold growth. 

Overall, it is safe to turn off all the water heaters when there is no water supply available to prevent them from damage. 

Tips for Turning Off Your Water Heater Properly

Follow the step below to turn off the water heater: 

Turn off the gas or the electric supply

Locate the gas switch near the water heater. 

You will find a valve near the water heater to turn off the gas supply. 

Flip the switch to turn it off. If you fear a carbon monoxide gas leak, disconnect the gas supply from your home. 

You can also seek advice from a professional in turning off the gas supply to the water heater. 

If you use an electric water heater, locate the main circuit breaker, you can see a separate breaker for the water heater. 

Flip the breaker to turn off the electric supply to the water heater. 

Cut the water supply.

If the water supply is already discontinued in your water heater, you can skip this step. 

Or else, you can locate the valve near the water tank, facilitating continuous water supply to the heater. 

Close the valve to block the water supply to the heater. 

Closing the water supply wall ensures your water heater is safe while on a long vacation. 

Drain the remaining water in the water heater

The last step is to drain the remaining water in the water heater. 

To do so, locate the spout at the bottom of the water heater. 

Direct the spout to the floor drain to expel standing water in the heater. 

How to Protect Your Water Heater During Water Outages? 

During water outages, it is important to prevent the water heater from being damaged. 

Follow the steps below to protect your water heater during a water outage: 

• If you use an electric water heater, turn off the power to the unit by flipping the circuit breaker to the off position. In case of using an electric gas heater, please turn off the gas valve near it to block the gas supply. It helps to prevent the water heater from internal damage. 
• The next step is to turn off the water inlet valve near the tank. Turning off the water inlet valve will block the entry of dirt and debris. 
• If the water outage lasts a few weeks, draining it from the tank is better. If the water is left in the tank, there are more chances of bacterial growth, including corrosion. You can prevent this by draining the water into the bucket. 
• After draining the tank, please protect it from debris and dirt accumulation by wrapping the blanket.
• When the water supply is restored, turn on the valve and let the water heater fill completely. Check if there are any leaks and cracks in the system. Repair it immediately to prevent water damage. 

The Impact of Water Outages on Your Water Heater’s Lifespan

A frequent water outage will have a serious impact on the efficiency of the water heater. 

It will also reduce the lifespan of the water heater. 

Here are the major impacts and how to prevent them: 

• When frequent water outages in your area cause sediment accumulation issues in your water heater, sedimentation causes corrosion and also causes cracks in the water heater. It is best to clean the sedimentation regularly to prevent the issue. 
• Switching the water heater during the water outage will cause overheating issues. A heating element in the water heater will continue to produce heat, resulting in internal damage to the water heater. 
• The water flow pressure will change when the water supply is restored after the water outage. This change in the water flow pressure will damage the water heater. It will cause cracks and damage the inner lining of the tank. 
• A frequent water outage causes corrosion in the water supply pipes. It results in the entry of debris particles into the heater. 

Steps you need to follow to prevent damage to the water heater

• To prevent damage to the water heater from occurring due to pressure fluctuation, you can install a pressure regulator to handle the pressure fluctuations of the water after the restoration of the water supply. 
• After the water outage, flush the water heater’s interior and tank to remove the sedimentation and other debris accumulation. 
• Mineral build-up in the water heater can be controlled by installing a water softener in the water tank. 
• Schedule professional water heater cleaning services to inspect its working condition. Clean the water heater regularly to prevent dust and debris accumulation during the water outage. 

The Importance of Conserving Energy and Saving Money by Turning Off Your Water Heater During Water Outages

When I talked about water outages and their impact on energy bills with my neighbor, he shared how he dealt with this situation efficiently. 

He said that during the last month, there were three water outages. 

It was terrible for him to deal with them as there would be a limited water supply. 

He was also worried about the water heater, which would get damaged due to frequent water outages. 

He also realized that continuous running of the water heater without the water supply would increase the energy bills. 

So, he turned off the water heater during every water outage last month.  

He said he noticed a significant fall in the energy bills at the month’s end. 

Due to this interaction with my neighbor, I understood the importance of turning off the water heater during a water outage. 

I decided to follow the same to conserve energy and prevent the water heater from getting damaged. 

You can also do the same to reduce your energy bills during water outages. 

Alternatives to Turning Off Your Water Heater During Water Outages

Many people hesitate to turn off the water heater as it may take time to heat it after restoring the water supply. 

If you feel the same, you can lower the temperature settings on your water heater. 

Or you can turn on the vacation mode on your water heater to prevent it from damage. 

Final thoughts

It is best to turn off the water heater if the water is off for the longest period. If there is a water outage in your locality or you are going on a vacation, in these two instances, leaving the water heater turned on will cause damage to it. 

There are chances of overheating, resulting in damage to the heating element. If the water is off only for a few hours, you don’t want to turn off the water heater. If you use a water heater with a tank, it is important to turn it off as there will be a steady flow of water from the tank. 

It is not the same in tankless water heaters. They are not prone to more damage like standard water heaters. I hope you would have got a clear answer to your question. 

 Reference:  Water heating Wikipedia

Sharing is caring!