Point-of-use (POU) electric tankless water heaters are compact, energy-efficient appliances that heat water on demand, directly at the fixture where it's needed. Unlike traditional tank water heaters, they eliminate standby heat loss and provide a continuous supply of hot water as long as the tap is running. This makes them an increasingly popular choice for supplemental hot water in homes, apartments, or even RVs. This guide delves into the advantages, disadvantages, and considerations for choosing a POU electric tankless water heater.
What is a Point-of-Use Electric Tankless Water Heater?
A point-of-use electric tankless water heater is a small, self-contained unit installed near a single fixture, such as a kitchen sink, bathroom sink, or shower. It heats water instantly as it passes through the heating element, eliminating the need for a large storage tank. This "on-demand" heating offers several benefits, including significant energy savings and the elimination of standby energy loss.
How Does a Point-of-Use Electric Tankless Water Heater Work?
These heaters operate using electricity to rapidly heat water as it flows through an internal heating element. When you turn on the hot water tap, a flow sensor activates the heating element. Cold water passes through the element, which quickly heats it to your desired temperature. The heated water then flows directly to the faucet. Once the tap is turned off, the heating element shuts down, preventing any wasted energy.
Advantages of Point-of-Use Electric Tankless Water Heaters
- Energy Efficiency: Because they only heat water when needed, POU electric tankless water heaters are far more energy-efficient than traditional tank water heaters, reducing your energy bills and environmental impact.
- Endless Hot Water: Unlike tank heaters with limited capacity, POU units provide a continuous supply of hot water, perfect for situations with multiple users or high hot water demands.
- Space Saving: Their compact size makes them ideal for smaller spaces where a bulky tank heater wouldn't fit.
- Easy Installation: Generally easier to install than tank heaters, particularly for supplemental hot water needs, often requiring only basic plumbing and electrical connections.
- Reduced Standby Heat Loss: The absence of a storage tank eliminates the constant energy loss associated with keeping a large volume of water hot.
- Improved Water Quality: Because the water is heated instantly, there's less chance of sediment buildup or degradation of water quality within the unit.
Disadvantages of Point-of-Use Electric Tankless Water Heaters
- Limited Flow Rate: POU electric tankless heaters may have a lower maximum flow rate compared to larger tank heaters, meaning the hot water output might be limited during periods of high demand.
- Higher Initial Cost: While long-term energy savings are substantial, the upfront cost of a POU tankless heater is generally higher than a comparable tank heater.
- Electrical Requirements: These units require a dedicated electrical circuit with sufficient amperage, potentially requiring electrical upgrades.
- Potential for Scalding: The rapid heating can lead to scalding if not properly adjusted or used cautiously. Temperature controls are crucial for safety.
- Not Ideal for Whole-House Heating: POU heaters are best suited for supplementing existing hot water systems or providing hot water for a single fixture; they are not designed to replace a whole-house water heater.
What are the Different Types of Point-of-Use Electric Tankless Water Heaters?
While most are similar in function, POU electric tankless heaters might vary based on factors like:
- Flow Rate Capacity: This determines the volume of hot water the unit can deliver per minute. Higher flow rates are better for applications requiring more hot water, like showers.
- Power Requirements: Units come in various power ratings, measured in kilowatts (kW). Higher kW ratings provide faster heating and higher flow rates but require more powerful electrical circuits.
- Installation Type: Some units are designed for under-sink or wall-mounted installation, while others might be more versatile.
How Much Does a Point-of-Use Electric Tankless Water Heater Cost?
The cost varies significantly depending on the brand, flow rate capacity, power requirements, and features. You can expect prices to range from a few hundred dollars to over a thousand dollars.
How Long Do Point-of-Use Electric Tankless Water Heaters Last?
With proper maintenance and use, a point-of-use electric tankless water heater can last for 10 years or even longer. Regular descaling (removing mineral buildup) is crucial for extending its lifespan.
Is a Point-of-Use Electric Tankless Water Heater Right for Me?
Consider these factors:
- Your Hot Water Needs: Do you need hot water for a single fixture or multiple fixtures?
- Your Budget: Can you afford the higher initial cost, even with long-term energy savings?
- Your Electrical System: Does your electrical system have the capacity to handle the added load of a tankless heater?
- Your Plumbing System: Is your plumbing system adequately sized to handle the flow rate of a tankless heater?
Careful consideration of these factors will help you determine if a point-of-use electric tankless water heater is the right choice for your specific needs. Consulting with a qualified plumber or electrician is highly recommended before making a purchase and installation.
