Dependent upon where you live, mild weather or harsh cold may be typical during the winter months. Regardless, your water heater must work harder when the temperature drops outside the house. This begs the question — can water heaters freeze?
Although very rare, it's definitely not impossible for a water heater to freeze. The primary concern is that any standing water inside the tank or tankless unit will freeze and expand, destroying the appliance in the process. If this happens, you may have no choice but to replace the water heater.
Today's water heaters are designed to remain operational no matter how cold it gets outside. Even so, it never hurts to take safeguards if a deep freeze is in the forecast, particularly if your water heater is installed outside.
Drain the Water Heater
Before leaving on an extended vacation this winter, give thought to bleeding out the water heater to prevent a plumbing crisis while you’re away. You may want to drain the tank if power is lost to avoid potential freezing. To provide greater comfort and security, you might choose to install a freeze protection solenoid valve, which opens automatically and drains the water heater during a power outage.
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 delivering power to the water heater.
- Fasten 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.
- Don't stop draining until the tank is empty, then close the valve.
Leave the Water Running
Think about letting a trickle of hot water flowing from a faucet or two until the cold snap subsides. The small increase you'll likely see on your next water bill is well worth avoiding a frozen water heater. This approach also helps avoid frozen and burst pipes.
Plumbing insulation is very affordable and comes in a variety of forms. You can insulate your water heater tank with a specific blanket to help reduce standby heat loss and deliver protection against cold weather.
Naturally, pipes are more likely to freeze than water heaters. In addition to running a trickle of hot water, you can cover exposed pipes situated outside or along exterior walls by wrapping them in foam insulation. Another option is to install electric heat tape to warm the pipes above freezing point. Only some 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 goal of this system is to transfer hot water to the tap faster, 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 warms the pipes during the cold months and makes your tankless water heater less likely to freeze. These bundled benefits could validate the installation cost, particularly in cold climates.
Select a Suitable Installation Spot
Most North American homes have indoor water heaters. However, in mild southern climates, water heaters are sometimes installed in the garage or even outside. While this approach is fine for those climates, the rare deep freeze can have ruinous effects on outdoor water heaters. As such, you should demand that your next water heater be placed inside, or at minimum in a covered spot 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. 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. Some have an electric element that yields a sufficient amount of heat to protect against internal freezing. Others light up the gas burners to heat a small amount of water and, in short, 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 switched on. Then, for protection during a power failure, look into purchasing 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.