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A hot water heater’s elements will get too hot and burn up or dry fire without water. If this happens for a long period, the elements will stop working.

What Happens If I Turn On A Water Heater Without Water?

Water heater elements work well when submerged in water. If you turn on a water heater without water, you risk exposing your water heater elements. They will heat up and get dry fired. Dry-fired heating elements will need replacement as they will stop working immediately or within a few days.

Furthermore, the heating elements can crack under heat pressure, and worst-case scenario, your tank may explode. Dry-firing can happen to both tank and tankless water heaters.

If there is a plumbing issue, like a leaking water heater, and you need to empty the tank, ensure you switch off the water heater to be safe.

How Long Can A Water Heater Go Without Water?

The recommended time your water heater should go without water is 24 hours. If there is a water outage, or for some reason, your water heater tank cannot get full, then you are required to turn off your water heater to avoid damage.

Once water is restored and your tank is full, you can switch the heater back on. This also applies to pressure levels for your tankless water heaters. Do not switch on your water heater until trapped air is expelled from the faucets and the water is back to full pressure.

How Does My Water Line Work With My Water Heater?

The water that flows through your home through the mainline has high pressure. This pressure allows it to travel at high speed and against gravity through the pipes to your home. One of the pipes is connected to your water heater.

Your water heater then connects to hot water lines that deliver water through pipes to appliances and facilities that need hot water.

When Is It Okay To Shut Off Water From Water Heater?

It is okay to shut off your main water supply in case of a plumbing emergency. You can also turn it off if you just plan to make fixtures in your home plumbing system for a short time.

If your water heater tank is leaking or a pipe connected to it is leaking, you may need to shut off the water until the problem is resolved to avoid energy wastage. You can do this through the shut-off valves at your water heater.

You will see two shut-off valves on your water heater, the cold water inlet, and the hot water outlet. The cold water inlet brings water from your main supply to your heater, while the hot water outlet expels hot water to your faucets. You need to shut off the cold water valve if you need to repair or replace your water heater.

If you have a hot water leak, you need to shut off the hot water valve so that no hot water leaves the water heater. This valve controls all the hot water in your home, so if there are multiple leaks, for example, from your showerheads, you will save energy wastage.

You can tell the two valves apart by color coding, blue for the cold water valve and red for the hot water valve.

When Should I Shut Off My Water Heater?

Your water heater does not only get damaged when the tank is empty. Some instances require you to turn off your water heater even when the tank is full.

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When There Is A Leak

When your water heater leaks, not only will you waste water, you will waste electricity as well. As the water heats, the portion that leaks is part of energy consumption. It is best to switch off your water heater until you address the hot water leaks.

When You Travel

If you plan to travel for an extended time, it would be best to leave your appliances in the best energy-efficient conditions. While shutting off the water heater is not as beneficial in power saving, some water heater owners may choose to do so.

If you have an older water heater model, it may not have some features that save on energy while you are away. In this case, you can either lower the temperature to about 50 degrees or turn off the water heater. Turning off your water heater could be beneficial in areas where power outages are an issue to avoid power surges that might damage your heater.

How Can I Tell If My Water Heater Has A Problem?

While shutting off your water supply or turning off your water heater are measures that most homeowners take to prevent water heater damage, it is best to note down some other problems. These problems are not related to your tank being empty or your water heater being off.

No Hot Water

If your water heater tank is full (or if you have a steady supply of water for tankless heaters), and you have no water, there might be a problem with your water heater’s heating elements.

The first thing to do is to check the electrical connection in your heater and ensure that the power is connected correctly and there are no loose wires. Call a plumber to check the heating elements if all the connections are okay and there is still no hot water.

If you are using a gas water heater, your pilot light is on, and no hot water is produced, you may have an issue with the burner or the gas flow and connection.

Extreme Water Temperatures

Sometimes water temperatures might be inconsistent and extreme, either too hot or too cold. In this case, the problem is with your thermostat. Even if you adjust your thermostat, the temperatures are still not adjustable.

You should have the thermostat just in case debris is interfering with its sensing power. If it still does not work, you may want to replace it.

Long Water Heating Time

Water heaters take 30 mins to one hour to heat water. However, if yours takes too long to heat, above three hours or so, there is a problem with the heating elements.

First, check your thermostat and ensure it is not set too low. If it is, then your heating elements will not output enough energy to heat your water quickly. For gas water heaters, it could indicate a poor gas connection or low gas pressure. A dirty burner or vent flue may also obstruct gas flow leading to a delay in heating water.

In some cases, your water heater has nothing to do with the delay in heating water. Instead, the problem is your household is too large for the water heater capacity you are using. Once it empties and refills, it is used up again before heating up again, so you can troubleshoot this to diagnose your water heater properly.

Discolored Water

You may notice that the water coming out of your faucet is brown or orange. Discolored water indicates corrosion in your water tank, and you should address it immediately. Corrosion occurs when the metals in your tank react to water in the presence of oxygen, and the by-product is rust that mixes with water.