Can Water Heaters Freeze?

Based on your location, mild weather or extreme cold may be the norm this winter. Either way, your water heater must work harder when the temperature drops outside. This begs the question — can water heaters freeze?  

Although very rare, it’s certainly not impossible for a water heater to freeze. The biggest concern is that any standing water inside the tank or tankless unit will freeze and expand, destroying the appliance along the way. If this happens, you may have no choice but to replace the water heater. 

Rest assured that water heaters are built to remain operational regardless of how cold it gets outside. Still, it never hurts to take safeguards if a deep freeze is in the forecast, especially if your water heater is installed outside. 

Drain the Water Heater 

Before leaving on an extended vacation this winter, consider draining the water heater to bypass a plumbing emergency while you’re away. You can also drain the tank if the power goes out to avoid potential freezing. For added protection, you might choose to install a freeze protection solenoid valve, which opens conveniently and drains the water heater during a power outage. 

Here’s how to accomplish this task yourself: 

1. Turn off the cold-water supply valve, gas supply valve, and temperature control knob. 

2. Flip the circuit breaker supplying power to the water heater. 

3. Fasten a hose to the drain valve or place a bucket under it to catch the water. 

4. Open the valve to start the flow of water. 

5. Keep draining until the tank is empty, then close the valve. 

Let the Water Run – A Little 

Consider leaving a trickle of hot water flowing from a faucet or two until the cold snap subsides. The resulting slight increase in your water bill is well worth avoiding a frozen water heater. This method also helps prevent frozen and burst pipes. 

Install Insulation 

Plumbing insulation comes in many forms. You can insulate your water heater tank with a specific blanket to help reduce standby heat loss and provide protection against cold weather.  

Of course, pipes are more inclined to freeze than water heaters. Along with running a trickle of hot water, you can protect exposed pipes found outside or along exterior walls by wrapping them in foam insulation. Another option is to install electric heat tape to keep the pipes just above freezing. Only a few types of heat tape are compatible with insulation, so read the instructions carefully if you plan to use them together. 

Put in a Hot Water Recirculation System 

The primary purpose of this system is to move hot water to the tap rapidly, shortening the wait time and reducing the amount of water that is wasted down the drain. A hot water recirculation system is convenient, water-wise and energy-efficient. It also keeps your pipes warm in the winter and makes your tankless water heater less likely to freeze. These combined benefits could justify the installation cost, especially in cold climates. 

Select a Suitable Installation Spot 

Almost all North American households have indoor water heaters. However, in mild southern climates, water heaters are occasionally installed in the garage or even outside. While this practice is perfectly safe most of the time, the unexpected deep freeze can have ruinous effects on outdoor water heaters. For this reason, you should demand that your next water heater be installed inside, or at the very least in a covered location sheltered from the wind. 

Choose a Water Heater with Built-In Freeze Protection 

Most tankless water heaters have built-in freeze protection that works in temperatures down to -22 degrees F. Don’t buy a tankless water heater without this feature, especially if the only option is to install it outside. 

Different brands use different freeze-prevention methods. Some have an electric element that yields just enough heat to prevent internal freezing. Others fire up the gas burners to raise the temperature of a small amount of water and, in turn, keep the tankless cabinet frost-free. 

No matter the method, water heater freeze protection is only effective when turned on. First, check the unit to make sure this feature is activated. Then, for protection during a power failure, consider investing in a small portable generator, whole-home standby generator, or battery backup power supply for your tankless water heater. 

Schedule Water Heater Services 

For answers to questions about your pipes or water heater potentially freezing this winter, turn to Service Experts Heating & Air Conditioning. Our well-trained plumbers can accomplish any water heater repair or replacement you need. We can also recommend steps to help your pipes and plumbing appliances last longer in any weather. For more information or to arrange a visit, please contact a Service Experts office near you today.