Action Furnace installs and services water heaters in Calgary, Red Deer, and Edmonton. Let us show you how these systems work and whether you can turn your water heater off to save money during periods when you’re away from home.
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Hot water plays a crucial role in your comfort and convenience at home. Still, there are times when you might need to turn off your water heater—for routine maintenance, safety, or energy-saving purposes. So how can you do it, and when should you?
We install new water heaters throughout Calgary, Edmonton, and Red Deer—so our team knows all about these critical systems and how to make the most of them. Read on and learn all about turning off your water heater so you can keep using it as efficiently as possible.

How Your Water Heater Works
In a tank-type water heater, cold water enters through a dip tube and is heated by a gas flame or an electric element inside the tank. The heated water rises to the top of the tank and is released through a heat-out pipe when you need hot water in your household. A pressure relief valve ensures safe pressure levels, preventing tank bursts and potential flooding.
Tankless hot water heaters work differently—heating water on demand as it passes through your plumbing system on the way to various water fixtures. Because tankless water heaters are only activated when you draw hot water from a fixture, we’re going to focus on hot water tanks here.
What Happens When You Turn Off Your Water Heater?
When you turn off your water heater, the water inside the tank cools, and turning off the water intake prevents the tank from refilling. As a result, you’ll eventually run out of hot water, impacting your daily routines, such as hot showers, dishwashing, and laundry.
Still, there are a few reasons why you might want or need to turn your water heater off temporarily. We’ll dive into those next.
Reasons You Might Turn Off Your Water Heater

You’re Going On Vacation
You might consider turning off the main water supply when going on vacation to reduce the risk of flooding if there’s a plumbing emergency. Some people also believe this is an effective way to save money.
While turning your water heater off during trips might seem like a smart move, it may not actually be necessary. Here’s why:
- Most modern water heaters have a vacation or “VAC” setting on them for this exact purpose. This setting allows you to lower the water heater’s temperature during your absence, reducing energy consumption without fully turning it off.
- You may save a tiny amount on your gas or electric bill, but the cost of reheating the water will likely make up the difference. The energy required to reheat the water to your desired temperature upon your return often offsets any money saved by turning it off.
- Having hot water on demand helps prevent your pipes from freezing. Be wary of turning off your hot water tank in very cold weather. Keeping the water heater running at a lower temperature while you’re away can protect your pipes from freezing and prevent potential damage.
Your Tank is Empty
If your hot water tank is empty and will not be refilled immediately, you actually should turn off your water heater. Leaving the water heater on when the tank is empty can lead to excessive heat buildup, potentially damaging the tank.
Several factors can cause your hot water tank to be empty:
- Leaks: If you notice a puddle of water around the water heater, it indicates a leak in the tank or its connections. In these cases, you’ll want to turn the water heater off immediately to avoid flooding and damage (see more on this below).
- Main Water Supply Shut-Off: If the main water supply is shut off for any reason, your water heater will not receive any water, and the tank will be empty. This can occur due to road work or construction happening in your area.

Your Hot Water Tank is Leaking
Leaking hot water tanks need to be addressed right away. Not only does a leaking tank pose a risk of flooding, but it can also indicate an underlying issue with the pressure regulation or the relief valve in your water heater. If too much pressure builds up inside the tank without proper relief, it can eventually burst, causing catastrophic damage.
If you ever notice a leak in your water heater, turn it off and call Action Furnace for water heater repairs. One of our qualified HVAC technicians will inspect your water heater, diagnose the issue, and carry out necessary repairs or replacement.
How to Turn Off Your Water Heater
If a situation arises where you need to turn off your water heater, make sure to follow the proper steps. This will help you turn off your water heater safely.
1. Disconnect the Power
For electric water heaters, locate the circuit breaker connected to the water heater and turn it off to cut the power supply.
For gas water heaters, turn the temperature dial all the way down to the “off” position. You will also need to ensure that the pilot light is no longer lit.

2. Turn Off the Water Supply
Locate the valve on the water supply pipe leading to your water heater. It should be labeled clearly with “on/off” positions. Turn the valve to the “off” position, which typically involves a clockwise turn to shut off the water supply.
For gas water heaters, the gas supply must also be shut off by turning the gas valve to the “off” position. However, only a professional should ever touch your home’s natural gas supply—call us for help with this instead of trying it on your own.
3. Drain the Tank
At the bottom of your water heater’s tank, there will be a drain valve. To avoid potential scalding, ensure you are wearing protective gloves or using appropriate tools to open the valve.
Attach a hose to the drain valve and direct the other end of the hose to a floor drain, tub, sink, or a bucket. If you choose to use a bucket, be prepared for multiple trips as the tank empties.
To facilitate the draining process, open a hot water faucet elsewhere in the house, which helps relieve pressure and allows the water to drain more effectively.
4. Turn Off the Relief Valve
The relief valve, also known as the pressure relief valve, is typically located close to the top of the water heater. Refer to your owner’s manual to pinpoint its exact location.
Turn the relief valve to the “off” position, allowing air to enter the tank as the water drains.
5. Try a Practice Run
It’s a good idea to go through a practice run of turning off your water heater before an emergency arises. Familiarize yourself with the location of valves and water/gas supply lines so that you know what to do in case of a leak, strange noises, or regular maintenance.
Bonus Tip: Avoid Frequent On/Off Cycles
In general, it’s best to keep your water heater full and heated throughout the year, avoiding frequent on-off cycles. Maintaining your water heater is the best way to keep it running smoothly and prevent untimely issues.
Annual water heater maintenance by our professionals ensures that your water heater is firing on all cylinders and helps detect potential problems before they become emergencies. You can also call us for help with any of the steps above if you feel uncomfortable tackling them on your own.

Getting Water Heater Help from Experts
Your water heater is an essential part of your home’s comfort and functionality. Understanding when and how to turn it off safely is vital for proper maintenance, safety, and energy efficiency.
When you need professional assistance or annual maintenance for your water heater, simply contact our experts at Action Furnace. We’re available 24/7 for any emergencies or questions you may have.
Frequently Asked Questions About Turning Off Water Heaters
Will Turning Off My Water Heater Save Money?
While turning off the water heater during extended absences can lead to slight energy savings, constant on-off cycles are not energy-efficient and might even incur higher costs. Consider using a water heater timer to ensure hot water is ready during peak usage times and track your usage for better optimization.
How Does a Water Heater Timer Save Energy?
A water heater timer can be used to optimize energy usage by ensuring hot water is available during peak times. Tracking your usage with data comparisons can help you understand the savings.
Should I Turn Off My Water Heater While on Vacation?
You may want to turn off your water heater while on vacation to reduce flooding risks. However, most modern water heaters have a vacation setting designed for this purpose, which prevents you from needing to turn the system off completely.
What Should I Do If My Hot Water Tank Is Leaking?
If your hot water tank is leaking, turn off the water heater immediately and contact our professional technicians to inspect and repair the issue.
Do I Have to Drain the Tank Before Turning My Water Heater Off?
Yes. Draining the tank is necessary if the water heater won’t be used for an extended period or if the tank is empty. This helps prevent heat buildup and potential damage.