Tankless Water Heaters Demystified: Everything You Need to Know
Choosing from all the tankless water heaters can be tough. With so many types and features, knowing which one fits your needs can be challenging. Tankless water heaters offer on-demand hot water without needing a storage tank.
This makes them more energy-efficient than traditional models.
These water heaters can save you up to 34% on energy costs compared to standard units. This blog will explain the different types of tankless water heaters, covering how they work and their pros and cons, and help you pick the best one for your home.
Ready to find your perfect water heater? Check out our top 10 recommendations for the best tankless water heaters!
Non-Condensing Tankless Water Heaters
Non-condensing tankless water heaters offer a simple way to heat water on demand. These units use a single heat exchanger to warm water quickly. They cost less upfront and are easier to install than other types.
Many homes and small businesses choose them for basic hot water needs. These heaters work well with natural gas or propane as fuel sources.
These water heaters have some drawbacks. They don’t reuse heat from exhaust gases, which lowers their efficiency. This can lead to higher energy bills over time. Regular upkeep is key to keeping them running well.
Users must clean vents and remove scale buildup often. When picking a non-condensing model, look at flow rates and energy input to match your needs.
How they work
Non-condensing tankless water heaters use a single heat exchanger to warm water. When you turn on a hot water tap, cold water flows into the unit. The flow sensor detects this and triggers the burner to ignite.
As water passes through the heat exchanger, it heats up quickly. The unit adjusts the flame to match the water demand, ensuring a steady hot water supply.
These units have a typical efficiency rating of 0.81 UEF. Due to high exhaust temperatures, they need metal venting. Navien offers several non-condensing models, such as the NHW-AI and NPN-U series.
These can provide up to 199,900 BTU/h of hot water output, meeting various household needs.
Pros: lower cost, simpler installation, reliable
Non-condensing tankless water heaters offer several benefits, including affordability, ease of setup, and dependable performance.
- Lower Cost: These units are cheaper than condensing models, making them a good choice for budget-conscious homeowners.
- Simpler Installation: They don’t need a drain, which makes setup easier. A plumber can install them quickly, saving time and money.
- Reliable Performance: These heaters have fewer parts, which means less can go wrong. They work well for years with little upkeep.
- Versatile Placement: The NHW-A and NPN series can be used indoors or outdoors, giving homeowners more options for where to put their water heaters.
- User-Friendly Features: Many models come with ComfortFlow® and NaviLink™, which make the heater easier to use and control.
- Energy-Efficient: While not as efficient as condensing models, they still use less energy than tank heaters, which can lead to lower utility bills over time.
Cons: lower efficiency, higher operating costs, limited temperature rise
Non-condensing tankless water heaters have drawbacks. These issues affect their performance and cost-effectiveness.
- Lower efficiency: These units waste heat through the exhaust, reducing efficiency. They typically operate at 80-85% efficiency, lower than condensing models.
- Higher operating costs: Lower efficiency leads to increased energy consumption, which results in higher utility bills over time, especially for households with high hot water usage.
- Limited temperature rise: Non-condensing units struggle to heat water quickly in colder climates. They may not provide enough hot water for multiple simultaneous uses, like running a shower and dishwasher at once.
- Increased energy consumption: These heaters use more fuel to maintain the desired water temperature, contributing to a larger carbon footprint.
- Less eco-friendly: The increased fuel use and lower efficiency make these units less environmentally friendly. They produce more greenhouse gas emissions compared to condensing models.
Condensing Tankless Water Heaters
Condensing tankless water heaters offer top-notch energy efficiency. They use exhaust gases to preheat incoming water, cutting energy use. These units work at lower temps, which boosts their thermal efficiency.
They can handle more hot water than standard electric models, making them great for busy homes.
Thanks to new technology and tough materials, these water heaters last longer and are kinder to the planet. By using waste heat, they cut down on greenhouse gases. The upfront cost is higher, but you can save money over time on energy bills.
Remember that you might need special venting due to the condensation they make.
How they heat water
Condensing tankless water heaters use two heat exchangers to warm water. The first exchanger heats incoming cold water with hot exhaust gases, and the second exchanger further warms the water to the desired temperature.
This two-step process boosts energy efficiency, allowing these heaters to achieve a Uniform Energy Factor (UEF) of up to 0.96. The high efficiency means less wasted energy and lower utility bills for homeowners.
These systems create condensation as they heat water, requiring a drainage setup. They offer flexible venting options, including PVC and polypropylene pipes. This makes installation easier in various home layouts.
The advanced technology in condensing tankless heaters provides hot water on demand while using less energy than traditional models.
Pros: higher efficiency (up to 98%), lower operating costs, eco-friendly
Condensing tankless water heaters offer big benefits. They stand out for their high efficiency, cost savings, and eco-friendly features.
- High Efficiency: These units can reach up to 98% efficiency, making the most of energy input.
- Lower Bills: Operating costs can be up to 50% less than standard hot water tanks.
- Energy Star Certified: Many models, like the NPE-2 series, have this stamp of approval for energy savings.
- Eco-Friendly: They use less energy, which means fewer carbon emissions and a smaller carbon footprint.
- Government Rebates: Installing these energy-efficient heaters may qualify you for money back from the government.
- User-Friendly Controls: Some models come with easy-to-use control panels for better management of hot water use.
- Reduced Energy Waste: They heat water on demand, reducing standby energy losses common in tank heaters.
Cons: higher initial cost, complex installation, requires maintenance
Condensing tankless water heaters come with some drawbacks. These cons may impact your decision to install one in your home.
- Higher upfront cost: Condensing units cost more than traditional water heaters, up to 1.5 to 2 times the price of standard models.
- Complex installation: Setting up these systems often requires expert help. You may need to upgrade gas lines or add new venting, which increases the cost.
- Regular maintenance: These units need yearly checkups to work well. You’ll have to clean the system and remove mineral buildup to keep it running smoothly.
- Special venting: Gas models often need extra venting, which can make the installation harder and more costly, especially in older homes.
- Possible retrofitting: Your home might need changes to accommodate the new system. This could mean updating pipes or electrical systems, increasing the overall cost.
Hybrid Tankless Water Heaters
Hybrid tankless water heaters mix the best of both worlds. They offer instant hot water, such as tankless units and a small backup tank. This setup works well for big homes with high water needs.
You won’t run out of hot water during peak times. The small tank keeps some hot water ready, while the tankless part heats more as needed.
These systems can save energy and money over time. They heat water fast and store some for later use, which means less wasted energy and lower bills. However, they cost more upfront and need more space than regular tankless heaters.
You’ll also need to clean them often to keep them working well. When picking a hybrid model, think about your home’s size, fuel type, and how much hot water you use.
Hot water generation
Hybrid tankless water heaters combine the best of both worlds. They use a small tank and a tankless unit to quickly make hot water. The tank holds some hot water ready to use, and when you need more, the tankless part kicks in.
This setup works well for homes that use a lot of hot water.
These systems often use heat pump tech to save energy. They can cut power use by up to 60% compared to standard tanks. But they cost more upfront and need more space. Still, their mix of instant and stored hot water suits many homes well.
Pros: combines tankless and storage tank benefits, suitable for high-demand
Hybrid tankless water heaters offer the best of both worlds and offer unique advantages for homes with high hot water needs.
- Unlimited hot water supply: These units can provide endless hot water like standard tankless heaters.
- Better for peak demand: The storage tank helps meet sudden spikes in hot water use, like running multiple showers at once.
- Energy savings: They use less energy than traditional tank heaters, which can lower monthly bills.
- Space-efficient: Hybrid models are more compact than full-sized storage tanks but offer similar capacity.
- Faster hot water delivery: The small tank allows quicker access to hot water than pure tankless systems.
- Suitable for large families: These heaters can handle the hot water needs of bigger households without strain.
- Reduced wear on components: The storage tank helps lessen the on-off cycling of the heating elements, potentially extending system life.
Cons: higher cost, requires more space, complex installation and maintenance
Hybrid tankless water heaters have some drawbacks. They are more expensive and require more attention than other options.
- More expensive: The initial price tag is often higher than standard tankless or tank models.
- Space requirements: They need extra room for the small storage tank and heating elements.
- Complex setup: Installation can be tricky, often needing changes to existing plumbing.
- Regular upkeep: These systems need more frequent checks and cleaning to work well.
- Skilled technicians: Repairs often require experts, which can add to long-term costs.
- Energy use: While efficient, they still use more power than pure tankless units.
- Water quality issues: Hard water can cause scale buildup, hurting performance over time.
Final Thoughts
Tankless water heaters offer many options for homeowners. Each type has its own strengths and weaknesses. Non-condensing units are simple and cheap but less efficient. Condensing models save energy but cost more upfront.
Hybrid systems blend the best of both worlds. Your choice depends on your needs and budget. Pick the right one, and you’ll enjoy hot water on demand for years to come.
FAQs
1. What are tankless water heaters?
Tankless water heaters, also called demand or instantaneous water heaters, heat water as needed without a storage tank. They offer reduced energy consumption compared to conventional tank water heaters.
2. How do electric tankless water heaters work?
Electric tankless water heaters use heating elements to warm water instantly. They’re efficient for small homes and don’t need venting like gas models.
3. What’s the difference between condensing and non-condensing gas tankless water heaters?
Condensing gas tankless water heaters recycle exhaust heat, making them more efficient. Non-condensing models vent hot exhaust directly outside, wasting some energy.
4. Can tankless water heaters handle high-demand situations?
Yes, but size matters. Larger units or multiple heaters can simultaneously supply hot water for dishwashers, clothes washers, and even hot tubs.
5. Do tankless water heaters need special installation?
Often, yes. They may require upgrades to gas lines, electrical systems, or venting. Professional installation ensures proper setup and safety.
6. How do tankless water heaters contribute to sustainability?
Tankless heaters reduce energy waste by heating water on demand. Some models work with solar water heating systems, further promoting clean energy use.
