Can Water Heaters Freeze?

Dependent upon where you live, mild weather or intense cold may be the norm this winter. Regardless, your water heater works harder when the temperature drops outside the house. This prompts the question — can water heaters freeze?

Although very rare, it's definitely not impossible for a water heater to freeze. The main concern is that any standing water within the tank or tankless unit will freeze and expand, permanently damaging the appliance along the way. If this happens, you may have few options but to replace the water heater.

Now, it’s worth mentioning that modern water heaters are built to stay operational no matter how cold it gets outside. Still, it is always prudent to take precautions if a deep freeze is in the forecast, particularly if your water heater is set up outside.

Drain the Water Heater

Before heading out on an extended trip this winter, give thought to draining the water heater to avoid a plumbing crisis while you’re away. You might also wish to drain the tank if there is a power blackout 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 disruption.

Here’s a step-by-step guide to walk you through it:

1. Shut off the cold-water supply valve, gas supply valve, and temperature control knob.
2. Flip the circuit breaker supplying electric service to the water heater.
3. Attach a hose to the drain valve or place a bucket under it to capture the water.
4. Open the valve to begin the flow of water.
5. Keep draining until the tank is empty, then close the valve.

Leave the Water Running

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

Install Insulation

There are many types of plumbing insulation that you can purchase. You can insulate your water heater tank with a specific blanket to help cut down on standby heat loss and give protection against cold weather.

Not surprisingly, pipes are more likely to freeze than water heaters. In addition to running a trickle of hot water, you can protect exposed pipes located outside or along exterior walls by wrapping them in foam insulation. It's also possible to install electric heat tape to keep the pipes just above freezing. Only certain 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 push hot water to the tap rapidly, decreasing the wait time and reducing the volume of water that pours down the drain. A hot water recirculation system is convenient, water-wise and energy-efficient. It also ensures your pipes are warmer and makes your tankless water heater less likely to freeze. These combined benefits could warrant the installation cost, especially in cold climates.

Pick a Suitable Installation Spot

The majority of 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 practice is fine for those climates, the unexpected deep freeze can have negative effects on outdoor water heaters. As such, you should insist that your next water heater be installed inside, or at the very least in a covered area sheltered from the wind.

Choose a Water Heater with Built-In Freeze Prevention

Most tankless water heaters have built-in freeze protection that works in temperatures down to -22 degrees F. The next tankless water heater that you buy should have this, especially if the only option is to install it outside.

Different products use different freeze-prevention methods. Many have an electric element that supplies an adequate amount of heat to protect against internal freezing. Others spark the gas burners to heat 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 activated. First, check the unit to make sure this feature is switched on. Then, for protection during a power failure, consider buying 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 possibly freezing this winter, turn to Service Experts Heating & Air Conditioning. Our well-trained plumbers can complete 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.