Can Water Heaters Freeze?

Depending on where you live, mild weather or intense cold may be the norm during the winter months. Either way, your water heater must work harder when the temperature drops outside the house. This begs the question — can water heaters freeze?

While extremely rare, it’s certainly not impossible for a water heater to freeze. The primary concern is that any standing water within the tank or tankless unit will freeze and expand, permanently damaging the appliance at the same time. If this happens, you may have few options but to replace the water heater.

Rest assured that water heaters are built to be operational despite how cold the temperature drops. Even so, it is always prudent to take safety measures if a deep freeze is in the forecast, particularly if your water heater is set up outside.

Drain the Water Heater

Before departing on an extended trip this winter, give thought to draining the water heater to bypass a plumbing crisis while you’re away. You might also wish to drain the tank if power is lost to avoid potential freezing. To provide greater comfort and security, you could install a freeze protection solenoid valve, which opens conveniently and drains the water heater during a power disruption.

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

    1. Shut off the cold-water supply valve, gas supply valve, and temperature control knob.
    1. Flip the circuit breaker providing power to the water heater.
    1. Connect a hose to the drain valve or place a bucket underneath it to catch the water.
    1. Open the valve to create the flow of water.
    1. Don’t stop draining until the tank is empty, then close the valve.

Let the Water Run – A Little

Think about keeping a trickle of hot water flowing from a faucet or two until the arctic cold weather subsides. The associated increase in your utility bill is well worth preventing a frozen water heater. This method also helps avoid frozen and burst pipes.

Install Insulation

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

Not surprisingly, pipes are more likely to freeze than water heaters. Beyond running a trickle of hot water, you can protect exposed pipes located outside or along exterior walls by wrapping them in foam insulation. Another option is to install electric heat tape to ensure the pipes don’t drop in temperature below 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 basic purpose of this system is to move hot water to the tap faster, decreasing the wait time and reducing the volume of water that flows down the drain. A hot water recirculation system is simple, water-wise and energy-efficient. It also warms the pipes during the cold months and makes your tankless water heater less susceptible to freezing. These paired benefits could warrant the installation cost, particularly in cold climates.

Pick a Suitable Installation Spot

The majority of North American households have indoor water heaters. Nevertheless, in mild southern climates, water heaters are sometimes installed in the garage or even outside. While this practice is fine for those climates, the unexpected deep freeze can have catastrophic effects on outdoor water heaters. Because of this, you should require that your next water heater be setup inside, or at minimum in a covered spot sheltered from the wind.

Choose a Water Heater with Built-In Freeze Protection

The majority 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 choice is to install it outside.

Different brands use different freeze-prevention methods. Many have an electric element that yields a sufficient amount of heat to avoid internal freezing. Others light up 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 successful when turned on. First, check the unit to make sure this feature is switched on. Then, for protection during a blackout, think about purchasing a small portable generator, whole-home standby generator, or battery backup power supply for your tankless water heater.

Schedule Water Heater Services

To learn more 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 suggest 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.

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