No, it is not okay to leave the heating elements or gas burner of a hot water heater on while the water supply is shut off. If the tank empties and the heater engages, it can rapidly overheat, destroy the heating elements, melt components, and cause extreme pressure buildups.
Without water flowing through the system, the heater risks overheating, leading to repairs water issues, melted parts, or even damage to your tank. Whether you own a gas water heater, an electric water heater, or a tankless water heater, the risks are real.
Potential Risks of Leaving It On
Leaving your water heater on during a winter vacation can pose several risks, including leaks and unnecessary energy consumption. Water heaters, especially older models, can develop leaks over time, which may go unnoticed if you're away. This can lead to water damage and costly repairs.
If you are leaving the house empty for more than a few days, it should be safe to leave your heating on, however, even if you do turn off the water. It can be useful to have your central heating ticking over on a low temperature while you're not there with the help of a smart thermostat.
So, the heater might not break right away. But this isn't always safe. If the tank runs dry and the heater keeps running, it can still overheat or break. That's why manufacturers recommend turning off heaters when the water is off.
Typically, if I turn off the water to my water heater, I would also turn off the power to the water heater. Water turned off won't prevent issues. The pipes would have to be DRAINED to avoid an issue. Otherwise it's just water sitting in the pipes that is going to freeze.
Shut Off The Water Heater
If you have a gas water heater, you can turn the heater off at the source and shut off the gas valve. If you have an electric heater, it can be turned off at the breaker. Once off, you can open the valve or spigot on the water heater to drain the water into a pail or bucket.
It takes time for your home to warm up and cool down. If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it.
Only heat the hot water twice a day
Try heating the water for an hour in the morning and an hour in the evening. Start the water heating about an hour before you need it. For example, if you shower at 08:30, start heating the water at 07:30. If you wash up in the evening at 19:30, then start the water heating at 18:30.
The good news is that no, it won't and this concern is based on a misunderstanding. The water that circulates through your boiler is not the same as the water coming out of your taps. The water heated by your boiler is part of a closed-loop system.
You can turn off the water at the water heater and still have cold water to use. When turning off cold water to the entire house, power to an electric water heater should be turned off, as well.
Yes, it is generally a good idea to turn off your water supply when you go on vacation, especially for extended periods. Before leaving, close your main water shut-off valve. Drain any residual water from the pipes by briefly turning on faucets after shutting off the main valve.
📌 Turning Off Your Water Heater Does Not Provide Significant Energy Savings For an average week-long vacation, turning off your water heater will not provide any significant energy savings. In fact, you're likely only to see a savings of a few cents a day depending on the make and model of your unit.
Electric tank water heaters hold hot water in a large insulated tank. In the event of a power outage: The preheated water remains hot for 1–2 hours if not used. If the tank is well-insulated and full, it can hold usable hot water for 6–12 hours, depending on ambient temperature and demand.
Over time, the constant operation can cause wear and tear on the heating element and other components. Additionally, the risks of geyser overheating become more pronounced, potentially causing damage to internal parts and impacting the overall lifespan of your appliance.
Look for the breaker labeled “Water Heater” to switch it off. This will help prevent any damage during the outage. For gas water heaters, locate the gas valve near the bottom of the unit and set it to “pilot mode” or the lowest temperature setting.
The average shower water usage is calculated by multiplying that average flow rate of 2.1 gallons per minute by the average shower length of 8.2 minutes. So, 17.2 gallons is, on average, how much water is used. In a 10-minute shower, you'll go through 21 gallons. Water used in the shower can add up.
For most customers, we recommend turning on your furnace when the weather is consistently below 18° Celsius, which usually happens to be around the end of September, or early October. Some homeowners try to put off turning on their furnace as long as they can to save money, which is okay if you're healthy adults.
Signs a Water Heater is Going Bad
To compensate for heat loss, you may need to slightly increase the water heater's thermostat setting during winter. The recommended temperature is between 120–140°F for most households.
Let's keep this short and simple: nothing ruins a home quite like water or fire. Water damage can result from frozen pipes, leaking supply lines, dripping water heaters, or other causes. Any damage will be greatly reduced by turning off the water before you go on vacation.
Q: Can a water heater freeze in a cold garage? A: It's possible, especially in very cold climates. To prevent freezing, ensure proper insulation on pipes, choose a model rated for cold environments, and consider installing a unit with built-in freeze protection.
When a cold snap hovers around or below 32 degrees Fahrenheit for a couple days in a row it's time to let at least one faucet drip. Pay close attention to water pipes that are in attics, garages, basements or crawl spaces because temperatures in these unheated interior spaces usually mimic outdoor temperatures.
Pipes can freeze in as little as six to eight hours, meaning they can freeze overnight. If the outside temperature is below 32F degrees and your pipes are unprotected, your chances for a frozen pipe increase.