All Your Questions About Tankless Water Heaters & Cold Weather, Explained
Tankless water heaters are a popular choice for energy-efficient and on-demand hot water. But if you live in a colder climate, you might wonder how well these systems hold up during freezing temperatures. Can they be installed outdoors? Will they freeze? Let’s break it all down.
Can Tankless Water Heaters Be Installed Outside in Cold Climates?
Yes, tankless water heaters can be installed outside, even in cold climates, but it requires proper preparation and installation. Modern tankless units are designed with freeze protection features, typically down to temperatures as low as -30°F. These features include built-in electric heaters and sensors that prevent the water in the system from freezing.
However, there are a few important factors to consider:
- Insulation: External pipes connected to the water heater must be insulated to prevent freezing. Heat tape or pipe wraps are great solutions for this.
- Shelter: Installing the unit in a covered or semi-enclosed space can shield it from direct exposure to wind and snow, enhancing its efficiency.
- Power Supply: Freeze protection systems rely on electricity, so it’s crucial to have a backup power source in case of outages during winter storms.
With these safeguards in place, outdoor installation is a viable option even in frigid conditions.
Do Tankless Water Heaters Freeze in Cold Weather?
While tankless water heaters are designed to resist freezing, extreme cold or improper installation can still pose risks. Here’s how to prevent freezing:
- Use the Freeze Protection System: Most tankless units have built-in protection, but this only works if the unit is plugged into a power source.
- Drain the System: If you expect prolonged periods of extreme cold and won’t be using the water heater, consider draining it. Many tankless models have a drain valve for this purpose.
- Maintain Flow: Allowing a small trickle of water to flow through the system can help prevent freezing. Moving water is less likely to freeze, even in cold weather.
- Regular Maintenance: Keep the unit free of debris, snow, and ice to ensure it operates efficiently and safely.
If a tankless water heater does freeze, never attempt to thaw it with an open flame. Instead, use a safe heating method, like a space heater or warm towels, and contact a professional plumber for assistance.
The Bottom Line
Tankless water heaters can absolutely handle cold weather when installed and maintained correctly. Whether installed indoors or outdoors, freeze protection systems, proper insulation, and proactive care are key to ensuring reliable performance in winter.
Need help choosing, installing, or maintaining your tankless water heater? Charlotte Plumbing’s experienced team is here to guide you every step of the way. Contact us today to learn more or schedule your service.









