Imagine waking up on a chilly morning, turning on the tap, and being greeted by icy water. Did you know that during cold weather, tankless water heaters can freeze, especially if installed in unheated areas or outside your home?
But don’t worry; in this blog post, I’ll show you simple steps to keep your outdoor tankless water heater from freezing. Let’s ensure you have hot water all winter long.
Keynote: How to Keep Outdoor Tankless Water Heater from Freezing?
To prevent your outdoor tankless water heater from freezing, insulate exposed pipes with polyethylene foam. Ensure the unit’s freeze protection feature is active and maintain electrical power. During extreme cold, let a hot water tap run slightly to keep water moving.
Why Outdoor Tankless Water Heaters Freeze
Outdoor tankless water heaters are efficient but vulnerable to freezing. Unlike traditional tanks that store hot water, tankless units heat water on demand. This design means no hot water reserve to prevent freezing during cold spells.
Key Vulnerabilities
- Exposure to Cold Air and Lack of Insulation: Outdoor units are directly exposed to cold temperatures. Without proper insulation, they can freeze quickly.
- Power Outages Disable Built-in Freeze Protection: Many tankless heaters have electric freeze prevention features. During power outages, these protections fail, increasing freeze risk.
- Standing Water in Pipes Freezes and Expands: Water left in the pipes can freeze, expand, and cause damage.
Fact: Temperatures below 20°F significantly increase the risk of freezing.
Comparison of Freeze Risks:
| Aspect | Tankless Water Heaters | Traditional Tank Water Heaters |
|---|---|---|
| Design | Heats water on demand; no hot water reserve to prevent freezing. | Stores hot water, providing a buffer against freezing temperatures. |
| Freeze Protection | Relies on electric freeze prevention features; vulnerable during power outages. | Maintains water temperature, reducing the likelihood of freezing even during power outages. |
| Vulnerability | Higher risk due to exposure and lack of stored hot water. | Lower risk due to stored hot water and continuous heating. |
Signs Your Heater is Freezing (and How to Spot Them)
Recognizing the signs of a freezing tankless water heater is crucial to prevent damage. If you notice no hot water or a significant drop in water pressure, it could indicate that your heater is freezing. Additionally, unusual noises like gurgling or visible frost on the pipes are clear indicators of freezing issues.
Comparison of Issues: Freezing vs. Other Problems:
| Symptom | Possible Cause |
|---|---|
| No hot water | Frozen heater or other malfunctions |
| Low water pressure | Frozen pipes or leaks |
| Gurgling noises | Air in pipes due to freezing |
| Visible frost on pipes | Freezing |
| Damp walls or ceilings | Leaks |
Acting quickly is essential. Thawing your system within six hours can prevent permanent damage.
7 Proven Ways to Prevent Freezing
Protecting your outdoor tankless water heater from freezing is essential. Here are seven proven methods to ensure your unit remains operational during cold weather.
1. Insulate Pipes and the Unit
Use foam sleeves or heat tape to wrap exposed pipes. Cover the heater with an insulated jacket designed for tankless units.
Insulation Materials:
- Foam sleeves
- Fiberglass wraps
- Heat tape
2. Install a Freeze Protection Kit
These kits activate heating elements when temperatures drop, preventing internal components from freezing. For example, the Rinnai Freeze Protection Solenoid Kit automatically drains the heater during power outages to prevent freezing.
3. Keep Water Moving
Allow a small trickle of water (0.1–0.2 gallons per minute) to flow through the system. Alternatively, install a recirculation pump to maintain water movement.
4. Winterize Your Heater
Steps:
- Turn off power and water supply.
- Drain the unit and disconnect hoses.
- Use antifreeze only if approved by the manufacturer.
5. Ensure Power Backup
Maintain power during outages using generators, solar panels, or battery backups.
Backup Options:
| Option | Cost | Efficiency |
|---|---|---|
| Generator | High | High |
| Solar Panels | Moderate | Variable |
| Battery Backup | Moderate | Moderate |
6. Leverage Built-In Freeze Protection
Many modern units have self-heating elements or freeze-guard modes. However, during prolonged power outages, these systems can fail. Always have a backup plan.
7. Shelter the Unit
Place the heater under a patio, inside a shed, or build an insulated enclosure to shield it from harsh weather.
Shelter Ideas:
- DIY wooden enclosure with insulation
- Professional-grade covers
- Installing the unit in a garage or basement
Implementing these strategies will help keep your outdoor tankless water heater functioning efficiently throughout the winter months.
Emergency Thawing: What to Do If It Freezes
If your outdoor tankless water heater freezes, act quickly to prevent damage. Here’s what to do:
- Turn Off Power and Gas: Immediately shut off the power and gas supply to the unit to ensure safety.
- Gently Thaw the Pipes: Use a hairdryer or space heater to warm the pipes. Avoid open flames to prevent damage.
- Inspect for Leaks: After thawing, check the unit and surrounding pipes for any leaks or damage.
Remember, delayed action can double repair costs.
Long-Term Maintenance for Freeze Prevention
Regular maintenance is key to preventing your outdoor tankless water heater from freezing. Here’s a simple checklist to keep your system in top shape:
- Annual Professional Inspections: Schedule a yearly check-up with a qualified technician to ensure all components are functioning properly.
- Monthly Filter Cleaning: Clean the inlet water filter(s) monthly to prevent debris buildup that can impede water flow.
- Bi-Annual System Flushing: Flush the system every six months to remove mineral deposits and maintain efficiency.
- Replace Worn Insulation Every 2 Years: Check and replace any worn or damaged insulation around pipes and the unit to maintain proper thermal protection.
Pro Tip: Set reminders to perform these tasks before winter arrives. This proactive approach ensures your heater operates smoothly during the cold months.
Final Thoughts
As we embrace the convenience of tankless water heaters, it’s essential to recognize the delicate balance between technology and nature. While these systems offer on-demand hot water, their vulnerability to freezing temperatures reminds us of the importance of proactive maintenance.
Consider this: a simple act of insulating your heater today can prevent significant disruptions tomorrow. By taking preventive measures, you’re not just safeguarding a device but ensuring the comfort and well-being of your household. In the dance between innovation and the elements, a little foresight goes a long way.
Keep Outdoor Tankless Water Heater from Freezing (FAQs)
How do I keep my tankless water heater from freezing outside?
To prevent freezing, insulate exposed pipes and the unit. Use heat tape or foam sleeves for pipes, and an insulated cover for the heater. Ensure the built-in freeze protection is active by keeping the unit connected to power. In extreme cold, let a faucet trickle to maintain water flow.
Do outdoor tankless water heaters need to be covered?
Yes, covering outdoor tankless water heaters is recommended. An insulated enclosure or cover protects the unit from harsh weather and reduces freezing risk. Ensure proper ventilation to prevent overheating.
How to insulate an outside tankless water heater?
Wrap exposed pipes with foam sleeves or heat tape. Use an insulated cover designed for tankless units to protect the heater. Ensure all connections are sealed to prevent cold air infiltration.
How to winterize an outdoor tankless water heater?
Turn off the power and gas supply. Shut off the cold water supply and drain the unit completely. Disconnect and drain all connected pipes. Cover the vent termination and exhaust to prevent debris entry.
Can a tankless hot water heater freeze?
Yes, tankless water heaters can freeze in cold temperatures, especially if not properly insulated or maintained. Freezing can cause significant damage to the unit and connected pipes.
Can I use antifreeze?
Using antifreeze in a tankless water heater is generally not recommended unless specified by the manufacturer. Instead, drain the unit and pipes if anticipating extended periods of non-use during freezing conditions.
How often should I drain the heater?
Drain your tankless water heater before extended periods of non-use during freezing conditions. Regular maintenance, including draining, should be performed as recommended by the manufacturer.
Should I turn it off in winter?
Keep the tankless water heater on during winter to allow built-in freeze protection to function. If you must turn it off, ensure the unit and pipes are thoroughly drained to prevent freezing.
How can plumbing professionals prevent burst pipes during freezing temps?
Plumbers recommend using polyethylene insulation on water pipes to prevent freezing and potential burst pipes. This insulation helps maintain pipe temperature, reducing the risk of major damage and costly repairs.
Do tankless water heaters have freeze protection features?
Yes, many tankless water heaters include built-in freeze protection features. However, these features require electrical power to function effectively. In power outages, additional measures may be necessary to prevent freezing.
Should water valves be adjusted during cold weather?
Yes, during freezing temperatures, slightly opening a hot water tap can keep water moving through the pipes. This practice helps prevent freezing and reduces the risk of burst pipes.
Can HVAC systems help prevent frozen pipes?
Yes, maintaining a warm room temperature with your HVAC system can prevent water pipes from freezing. Ensuring consistent indoor warmth reduces the likelihood of major damage due to frozen pipes.
Mark Bittman is a public health expert and journalist who has written extensively on food, nutrition, and healthy living. He has a wealth of knowledge to share when it comes to solving problems with appliances. In addition, he can help you choose the right appliances for your needs, optimize their performance, and keep them running smoothly.