When considering the installation of a tankless water heater, a key concern often arises: Do these heaters function during power outages? Unfortunately, the short answer is NO.
The absence of electricity renders a tankless water heater inoperative. This limitation stands as a notable downside of opting for a tankless system. However, it’s not a situation devoid of solutions. This article presents various strategies to ensure hot water availability during power outages.
Traditional tank-style water heaters come with the inherent advantage of storing hot water. In the event of a power outage, these systems still have a large, insulated tank full of hot water ready for use. In contrast, tankless systems operate differently. They do not store hot water but instead heat water on demand, making them dependent on a continuous power supply.
Electric tankless water heaters are particularly energy-intensive. Their operation can be so demanding that some households may need to upgrade their electrical systems when switching to a tankless model. For instance, whole-house tankless units often have four 7,000-watt heating elements, drawing a staggering 28,000 watts during operation. This high energy requirement underscores their reliance on a stable electrical supply.
Even in the case of gas-fueled tankless water heaters, electricity plays a vital role. Critical components such as the control panel, fans, flow sensors, thermostat, and pilot light require electrical power. Without electricity, these heaters cannot regulate temperatures, control water flow, or ignite the burners. This dependency on electricity for essential functions means that, like their electric counterparts, gas-fueled tankless water heaters are also rendered non-functional during power outages.
How Tankless Water Heaters Operate
Tankless water heaters are designed to provide hot water instantaneously. When a tap is opened, cold water travels through a pipe into the heater, rapidly heated by either an electric element or a gas burner.
This process ensures a continuous hot water supply, using natural gas, propane, or electricity as the heating source. Gas-powered heaters often have a higher flow rate, making them favorable for larger households.
The Essential Role of Electricity in Tankless Water Heaters
A common misconception is that gas or propane tankless water heaters can operate independently of electricity. However, even these models typically require an electrical connection. They rely on a PC board and a digital remote for operation, which serve as the control system. This system detects water flow and activates the heating mechanism.
Most modern gas and propane heaters use direct electric ignition instead of a pilot light, necessitating a 120V AC power supply, standard in most U.S. homes.
Tankless water heaters are celebrated for their energy efficiency, being 8–50% more efficient than traditional tank heaters. Gas and propane variants use minimal electricity, ensuring cost-effective operation. Their installation is relatively straightforward, connecting easily to a home’s electrical system.
Solutions for Operating Tankless Water Heaters During Power Outages
Options include integrating tankless water heaters with alternative systems like solar water heaters or using battery backups for the control components. These backups can enable gas or propane heaters to function temporarily without an electricity supply.
If you’re contemplating a tankless system but are worried about frequent power disruptions, here are some effective solutions to ensure an uninterrupted hot water supply.
Water Heater Backup Battery
A backup battery specifically designed for tankless water heaters is one of the most practical solutions. These compact, easy-to-install units are plugged in and ready to power during outages. They can offer up to 14 hours of continuous hot water supply or up to 7 days of regular usage during extended power failures.
Before purchasing a backup battery, it’s crucial to consult with your water heater technician and the manufacturer to ensure compatibility with your specific tankless water heater model. Backup batteries are particularly suitable for gas-fueled tankless heaters as they require minimal electricity, primarily for the pilot light and control panel.
A backup battery might not be the most feasible solution for electric tankless water heaters, which demand a significant amount of electricity to heat the water. In such cases, considering a generator could be a more effective option.
Back-Up Generator
Generators offer a robust solution for ensuring power supply to your tankless water heater during outages.
There are various types, each suited to different needs:
- Whole-House Generators: These are powerful units capable of powering an entire home. They are ideal for remote locations or areas frequently experiencing power outages, especially in the northern hemisphere, where heating is critical. Although they deliver substantial power, they can be bulky and require considerable fuel.
- Point-of-Use Generators: A point-of-use generator can be a smart choice for less frequent power outages. This type of generator is designed to power single appliances. You can turn it on only when you need hot water, conserving fuel. These generators can also be used for dishwashers or washing machines.
When choosing a generator, ensure it can power your tankless water heater. Consulting with a professional before purchasing is advisable to match the generator’s output with the heater’s power requirements.
Solar Water Heaters
A solar water heater is another alternative to consider, particularly for those seeking a more sustainable solution. These systems harness solar energy to heat water. They can be an excellent backup or complementary to a tankless water heater. Solar water heaters can provide hot water during power outages, assuming adequate solar exposure.
Effective Management of Tankless Water Heaters During Power Outages
Power outages can challenge the functionality of tankless water heaters, especially when relying on backup batteries or generators. It’s crucial to adjust how the water heater is used to maximize its efficiency during such times. Here’s a checklist to help manage your tankless water heater effectively during a power outage:
Adjust the Temperature Setting
One of the simplest yet most effective steps is to adjust the temperature of your tankless water heater. Set the temperature to a level that’s just hot enough for comfort without mixing in cold water. This reduces the energy required to heat the water, allowing your backup power source to last longer.
Turn Off Recirculating Pumps
Many tankless water heaters are equipped with recirculating pumps as an external addition or a built-in feature. These pumps continuously circulate hot water through the pipes for instant access, which can be an unnecessary power drain during an outage. Ensure that any recirculating pump connected to your tankless water heater is turned off to conserve energy.
Optimize Usage of Multiple Units
In homes with multiple point-of-use tankless water heaters, it’s important to strategize their usage. Having all units operational simultaneously can overburden your backup power system. Instead, prioritize using one unit at a time – for example, the one connected to your shower or kitchen. You can switch between units based on immediate needs, like taking a hot shower, washing dishes, or doing laundry. This selective usage helps to optimize power consumption and extend the operational time of your backup system.
The journey through understanding and managing tankless water heaters during power outages culminates in a blend of preparation and adaptation. While it’s clear that these advanced systems do depend on electricity to function, this doesn’t mean you’re left without options when the lights go out.
Homeowners can ensure a continuous hot water supply, even when the power goes out, by exploring solutions like backup batteries, generators, and solar water heaters.
In conclusion, the transition to a tankless water heater system, despite its reliance on electricity, does not have to be a vulnerability in power outages. With the right preparation and understanding of managing these systems under different conditions, homeowners can enjoy the benefits of tankless water heaters — efficiency, space-saving, and on-demand hot water — without fearing being left in the cold during power outages.
