Why Tankless Water Heaters Are Prone to Freezing

Before we jump into the prevention tips, let’s talk about why tankless water heaters tend to freeze more easily than traditional ones. Understanding this will help you see why it’s so important to take the right precautions.

What Makes Tankless Water Heaters Vulnerable

Tankless water heaters heat water as you need it, right as it flows through the unit. Unlike old-school heaters that store hot water in a big tank, these are smaller and hook directly into your water lines. Because they’re not storing water, they’re more exposed to the cold, which means the internal pipes and vents can freeze up if temperatures drop too low.

How to Spot a Freezing Issue Before It’s Too Late

Catching the signs that your heater is at risk of freezing early can make a big difference. If you notice that your water flow has slowed down significantly, it might be a sign that ice is forming inside the pipes or the unit. Another red flag is odd noises, like cracking or popping, which could mean ice is expanding inside the system. Many modern heaters also display error codes when something’s wrong, so if you see one during a cold snap, freezing could be the issue.

Steps You Can Take to Prevent Freezing

Keeping your tankless water heater from freezing is actually pretty straightforward. Just add some insulation, grab the right gear, and do a bit of regular maintenance. Follow these easy steps, and your heater will stay safe and sound through the cold weather.

Insulate Everything You Can

One of the simplest and most effective ways to avoid frozen pipes is to insulate both the inside and outside pipes linked to your heater. First, pick out the right insulation material—foam pipe insulation or heat tape made for outdoor use are great choices for most climates. Be sure to cover all exposed pipes, especially those outside or in unheated spots like basements or attics. If you’re in a really cold area, wrapping the whole unit in a thermal blanket can help keep the warmth in.

Get a Freeze Protection Kit Installed

If you live in an area where freezing temperatures are common, installing a freeze protection kit is a smart move. These kits usually include heating elements that keep the internal components of your heater warm enough to prevent freezing. Some even have sensors that automatically kick on the heating elements when it gets too cold. While it’s possible to install these kits yourself, we recommend getting a professional to do it. They’ll make sure everything’s installed correctly, and it’ll give you peace of mind knowing your heater is well-protected.

Keep the Power On

It’s crucial to keep your tankless water heater powered on during the winter, even if you’re not using it much. Most modern heaters have built-in freeze protection, but these features only work if the unit has power. If the electricity goes out, your heater is at risk of freezing. To avoid this, consider setting up a backup power source like a generator. This way, your heater will stay operational even during a power outage. Also, during periods of low usage, set your heater to a “vacation mode” or a low-temperature setting to keep water circulating without wasting energy.

Know When to Drain Your Unit

If you’re expecting extreme cold and can’t ensure your heater will stay powered or insulated, draining the unit might be the safest bet. This is especially important if you’re leaving home for a while during the winter or if a severe cold snap is on the way. To drain the unit, first turn off the water supply. Then open the unit’s drain valve and let all the water flow out. If you have access to compressed air, use it to blow out any remaining water in the lines. When the weather warms up again, carefully refill the unit and check for leaks before turning it back on.

Routine Maintenance to Keep Freezing at Bay

To keep your tankless water heater in top shape and prevent freezing problems, regular maintenance is key.

What to Check Regularly

Take a few minutes at the start of the cold season to inspect the insulation around your pipes and unit. Look for any gaps or spots where the insulation might have worn away. If you have a freeze protection kit installed, make sure it’s working properly—test it out if possible. Also, pay attention to the water flow and temperature during cold spells. If anything seems off, it’s worth investigating sooner rather than later.

Get Professional Help When Needed

It’s a good idea to have your tankless water heater inspected by a professional once a year, ideally before winter hits. They can spot potential issues and handle any maintenance that’s needed to prevent freezing. Some HVAC companies even offer winterization services, which include a thorough check and any adjustments necessary to keep your heater safe from the cold.

What to Do If Your Heater Freezes Anyway

Sometimes, despite your best efforts, your tankless water heater might still freeze. If this happens, quick action can help minimize the damage.

First Steps to Take

If you think your heater might be frozen, the first thing you want to do is cut off the power to it. This will help avoid any electrical issues or potential fire hazards. After that, turn off the water supply to prevent any leaks once the ice begins to melt. If the freeze doesn’t look too bad, you can let the unit thaw out on its own. Just steer clear of using open flames or other direct heat sources, as they could make things worse.

How to Safely Thaw Your Heater

To thaw your pipes, grab a hairdryer or a space heater. Start warming up the area closest to the heater and move outward. After the ice has melted, take a good look at the pipes and the unit for any leaks. If you spot any damage, it’s a good idea to call in a pro to check things out and handle the repairs.

When It’s Time to Call in the Pros

If your tankless water heater is still frozen after you’ve tried thawing it out, or if you notice significant damage, it’s time to call a professional. Trying to fix a frozen water heater on your own can lead to more problems and might even void your warranty.

Wrapping It Up

Taking the time to protect your tankless water heater from freezing can save you a lot of hassle and expense down the line. By insulating your pipes, installing a freeze protection kit, keeping the power on, and knowing when to drain the unit, you can keep your heater running smoothly through the coldest winter days. And don’t forget, regular maintenance is your best friend when it comes to preventing issues like freezing. Stay proactive, and you’ll enjoy a reliable supply of hot water all winter long.

FAQs

How often should I check the insulation on my pipes?

It’s a good idea to check the insulation on your pipes at the start of the cold season and then periodically throughout the winter to make sure it’s still in good shape.

Can I install a freeze protection kit myself?

While some people with plumbing experience might feel comfortable installing a freeze protection kit, we recommend having a professional do it to ensure it’s installed properly.

What should I do if my tankless water heater freezes while I’m away?

If you’re not home when your heater freezes, see if a neighbor or a professional can check it for you. They should turn off the power and water supply to prevent any further damage.

Are there specific brands of freeze protection kits that are better?

It’s best to use a freeze protection kit that’s recommended by the manufacturer of your tankless water heater, as it will be designed to work best with your specific model.

Can a frozen tankless water heater be repaired, or does it need to be replaced?

In many cases, a frozen tankless water heater can be repaired if the damage isn’t too severe. However, if there’s significant damage, especially to the internal components, you might need to replace the unit.