Can Water Heaters Freeze?

Based on your location, mild weather or severe cold may be typical during the winter months. Either way, your water heater has to work harder when the temperature drops outdoors. This prompts the question — can water heaters freeze?

While extremely rare, it's certainly not impossible for a water heater to freeze. The main 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 few options but to replace the water heater.

Rest assured that water heaters are built to be operational no matter how cold the temperature drops. Nonetheless, it never hurts to take safeguards if bitter cold temps are heading your way, especially if your water heater is placed outside.

Drain the Water Heater

Before leaving on an extended vacation this winter, give thought to draining the water heater to prevent a plumbing disaster while you’re away. You can also drain the tank if power is lost to avoid potential freezing. As an added precaution, you may want to install a freeze protection solenoid valve, which opens conveniently and drains the water heater during a power failure.

Here’s how to drain a water heater tank by hand:

Shut off the cold-water supply valve, gas supply valve, and temperature control knob.
Flip the circuit breaker providing electric service to the water heater.
Connect a hose to the drain valve or place a bucket underneath it to capture the water.
Open the valve to start the flow of water.
Keep draining until the tank is empty, then close the valve.

Leave the Water Running

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

Install Insulation

Plumbing insulation is very affordable and comes in a variety of forms. You can insulate your water heater tank with a unique blanket to help minimize standby heat loss and give protection against cold weather.

Not surprisingly, pipes are more prone 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 some types of heat tape are compatible with insulation, so read the directions for use 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 faster, decreasing 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 warms the pipes during the cold months and makes your tankless water heater less prone to freezing. These paired benefits could validate the installation cost, especially in cold climates.

Choose a Suitable Installation Spot

Almost all North American homes have indoor water heaters. However, in mild southern climates, water heaters are occasionally installed in the garage or even outside. While this approach is reasonably safe in those specific climates, the occasional deep freeze can have negative effects on outdoor water heaters. Because of this, you should demand that your next water heater be placed inside, or at minimum in a covered area sheltered from the wind.

Choose a Water Heater with Built-In Freeze Safeguards

A large number of tankless water heaters have built-in freeze protection that works in temperatures down to -22 degrees F. Make sure your next water heater has this feature, especially if the only option is to install it outside.

Different manufacturers use different freeze-prevention methods. Many have an electric element that provides an adequate amount of heat to avoid internal freezing. Others spark the gas burners to raise the temperature of a small amount of water and, in turn, keep the tankless cabinet frost-free.

Whatever the method, water heater freeze protection is only effective when utilized. First, check the unit to make sure this feature is activated. Then, for protection during a power outage, look into buying a small portable generator, whole-home standby generator, or battery backup power supply for your tankless water heater.

Schedule Water Heater Services

For more information about your pipes or water heater possibly 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 plan a visit, please contact a Service Experts office near you today.