
It can be difficult to find the right tankless water heater for you and your home, so we’ve created this guide and gathered some options for you to consider.
Buying Guide for Tankless Water Heaters

Why buy a tankless water heater?
Tankless water heaters have become a rather popular alternative to water heater tanks for a variety of reasons. For one, many tankless water heaters are incredibly energy efficient, especially when used in households that limit their hot water usage. They also tend to enjoy a longer lifespan than tank systems and take up a fraction of the space. Since they heat up much less water at any given time than tank systems, they can also provide you with hot water quicker than most water heater tanks on the market.
What should you look for in a tankless water heater?
- Output: Perhaps the most important factor to consider is a water heater’s hot water output, measured in GPM (gallons per minute). If you want to be able to take a hot shower while washing clothes as another family member is running the dishwasher, a high output will be necessary. Luckily, it’s not difficult to calculate the GPM requirements of various devices in your home to ensure that your new tankless water heater can keep up with the hot water demands of your household.
- Indoor vs. Outdoor: Indoor and outdoor units both come with advantages and disadvantages. If you’re using a gas-powered tankless water heater, housing the unit outdoors will eliminate the need for venting, which can be a costly installation when using an indoor unit. However, outdoor units can be exposed to extreme weather. While outdoor models are usually built durably so that they can endure all types of climates, if you live in an area that’s primarily freezing cold, an indoor tankless water heater might be a better option for you. However, outdoor systems are usually easier to install and less expensive than their indoor counterparts.
- Gas vs. Electric: Choosing between a gas or electric tankless water heater can also be tricky. Electric units score points for needing minimal maintenance to operate at their best. They also don’t need to be vented, which can greatly cut down your system’s installation cost. However, electric systems tend to consume more energy than gas-powered tankless water heaters. Natural gas or propane tankless water heaters are known for faster heat output but will have to be vented if housed indoors. Additionally, they tend to cost more than electric units and require more routine maintenance.
Is a tankless water heater ideal for your home?
There are plenty of factors to consider when considering whether your situation is ideal for a tankless water heater. One is the temperature of the water that enters your home. If your area is normally freezing cold, it will take much more energy for your tankless water heater to produce hot water, thereby minimizing your potential energy savings year after year. Another is the size of your family and your typical water usage. While some heavy-duty tankless water heaters out there work well for large households, the average (and inexpensive) tankless system is better suited for smaller households and one- to four-person families. One of the most attractive aspects of tankless systems is the energy savings over time. While large families with heavy hot water demands will likely see some energy savings year after year, it’s smaller families with moderate water usage that will really be able to take advantage of the savings that come from switching to a tankless water heater.
Our Picks for the Best Tankless Water Heaters
Rinnai V94iN
Thanks to its energy-efficient design and high-capacity flow rate, this is an ideal choice for large families who use a lot of hot water.
Pros: If you have a large family or high hot water demands, this is the system for you. The V94iN will allow you to run several showers simultaneously without breaking a sweat. It’s also a great choice for people who live in cold climates, as freezing temperatures will naturally lower the GPM of your tankless water heater. As a bonus, this model doesn’t take long to start working, so you won’t have to stand around waiting to enjoy your hot, relaxing shower.
Cons: Since this is a natural gas tankless water heater, you can definitely expect a pricey installation process. Additionally, there will be more routine maintenance to perform versus similar electronic units, which will affect the long-term cost-effectiveness of the unit.
Bottom Line: Tankless water heaters can be a risky proposition for large households with lots of family members and multiple bathrooms, but this one is really worth its weight in gold. While the elevated maintenance demands will likely turn some folks away, this is still the best choice available for people with heavy-duty hot water needs.
EcoSmart ECO 11
This budget-friendly electric tankless water heater is a reliable and cost-effective solution for singles and many couples.
Pros: This is an ideal unit for singles or for couples who tend to limit their hot water usage. While its low price tag might be its standout feature, this unit also impresses thanks to its intuitive digital temperature control interface and fast-working design. As a bonus, this tankless water heater will require very little in the way of maintenance after it’s installed.
Cons: Most families will have to look elsewhere for a hot water solution since this unit is unable to provide enough water for multiple appliances at once. If you live in a cold area, this is especially true, so you’ll likely need to make a larger investment in order to find a suitable product for your needs.
Bottom Line: Although this tankless water heater isn’t for everyone, it’s still a great choice, with a wide array of suitable applications. It’s also a thrifty option for people who live in warmer regions and are OK with modifying their hot water usage in order to save money over time.
Rheem RTEX-18
This easy-to-install electric tankless water heater provides a serviceable flow rate despite its lower power consumption.
Pros: The Rheem RTEX-18 stands out as one of the more convenient electric tankless water heaters you can purchase. For one thing, it’s much easier to install than similar units, and thanks to its low amperage, you can probably get it set up without needing to upgrade your home’s electrical grid. It also sports a respectable flow rate for its affordable price, making it a great choice for two- to three-person households.
Cons: Under ideal circumstances, this unit sports a 4.4-GPM flow rate, and larger families might find this to be less than ideal, especially when it gets frosty outside. If other people use water while you’re in the shower, you’ll likely notice some temperature fluctuation.
Bottom Line: This isn’t the most powerful electric tankless water heater out there, which can be a real positive or negative depending on how you look at it. On one hand, it’s a great cost-saving option for smaller households who don’t want to upgrade their electricity setup in order to install a new water heater. On the other hand, you can find similarly priced models with more power if you have more demanding hot water needs.
Rinnai V65iP
This high-efficiency system has the output necessary for multiple people to take showers at once, even when the temperature outside starts to drop.
Pros: Even when compared to other gas-powered options, the V65iP works quickly and efficiently so that you can turn on the shower and hop in almost immediately. It also sports an above-average water output that should exceed the needs of the average household. This unit also scores top marks in terms of energy efficiency, making it a great option for people who want to get the best bang for their buck.
Cons: While this unit’s price isn’t outrageous considering its above-average output, the hidden costs of installation and routine maintenance can be enough to cause some to reconsider its value. However, these costs will be somewhat counterbalanced by this unit’s impressive energy efficiency.
Bottom Line: Sporting a 6.5-GPM flow rate in ideal conditions, this tankless water heater is definitely suitable for people with elevated hot water needs. Even in near-freezing weather, you should be able to run several showers simultaneously without a hitch. While this unit will require a higher investment than others, this is to be expected for a high-output water heater.
RecPro RV Tankless Water Heater
This water heater is an excellent solution for RV and camper showers thanks to its straightforward installation process and frost-resistant design.
Pros: This reliable water heater is fairly straightforward to install, so if you’ve earned your DIY stripes by modifying your RV, you shouldn’t have too much trouble. It’s also easy to use thanks to the included remote control, and it sports frost prevention to keep your shower working in cold climates. Ultimately, people who are upgrading older, less-effective units will be amazed at how luxurious a hot RV shower can be.
Cons: As most would expect, this isn’t a device that will allow you to take a long, hot shower in your RV. However, for the needs of most RV enthusiasts, it should be more than adequate. It’s also important to note that the frost-prevention function requires both a 12V and a propane power connection, which somewhat limits its usability.
Bottom Line: Tankless water heaters could be incredibly difficult (and costly) to implement in your RV, so this unit is bound to save you time and money based on how easy it is to install. It’s also one of the more reliable options out there, even if it’s by no means a world-beater in terms of hot water output.
Final Thoughts
Tankless water heaters can be an amazing upgrade over your old water heater tank, but serious consideration should go into which model is right for you. If you fail to plan ahead and consider all of your needs, things can definitely go off the rails quickly. However, due to their longevity, energy efficiency, and space-saving designs, it’s no wonder that so many people choose to upgrade their water heaters.