Best Gas Tankless Water Heaters Reviews and Buyer Guide

Signs of A Busted Water Heater

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Gas tankless gas heaters are increasingly becoming popular. This is because they provide hot water on demand, so no time is spent waiting.

Even better, these heaters are more energy efficient when compared to conventional varieties.

In some cases, homeowners who install these tankless heaters quality for tax incentives of up to $300.

If you are looking to save on energy costs and get enough hot water whenever you want, below are the best gas tankless water heaters available.

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What is the Best Tankless Gas Water Heater?

The best gas tankless water heater is GASLAND Outdoors BS158 instant propane water heater.

Also Read: How To Test The Water Heater Thermostat in 10 Simple Steps

It’s a CSA approved water heater meeting both US and Canadian standards.

The unit is equipped with anti-freezing protection, flame failure device, and an overheating protection feature that ensures the safety of everyone in the house.

It’s lightweight and compact design makes it easy to carry. Thus, the heater is ideal for use at home, camping and at the beach.

With 41,000btu per hour, this unit provides endless on demand hot water without delays.

The manufacturer has incorporated 11.5% energy saving technology. This feature will save you on energy bills compared to traditional water heaters.

A-List of the Best Tankless Gas Water Heaters?

If GASLAND Outdoors BS158 doesn’t sound like the real deal to you, then there are other great alternatives to choose from. Below is a detailed review guide.

1. Rinnai RUC98iN

Rinnai RUC98iN

The Rinnai RUC98iN is perfect if yours is a large family. The heater is suitable for households where hot water is in high demand.

The fact that it uses natural gas in place of electricity means that it is a much cheaper option.

Thanks to the advanced technology, the heater is ultra-efficient, and you get hot water instantly with minimal, if any, energy wastage in the process.

The RUC98iN comes with a metallic finish making it perfect for appliances with the same color.

In addition, the heater has a sleek and compact design ideal for small spaces and indoor installation.

As far as performance is concerned, this natural gas heater delivers up to 0.96 Energy Factor, 199,000 BTU, AND 95% Thermal Efficiency.

The heater has extremely low emissions, which makes it environmentally friendly.

Click here to buy it on Amazon.

2. Rheem RTGH-95DVLN


Rheem is among the most trusted brands, and for a good reason too.

The manufacturer provides durable and efficient natural gas water heaters in the market.

The RTGH-95DVLN is not any different.

This water heater is designed to provide up to 9.4 gallons of hot water every minute.

Thanks to its stainless-steel condensing water exchanger, this water heater needs less energy to heat water to the desired temperature.

The intelligent electronic controls further enhance the heater’s efficiency and safety.

Like any other good gas tankless water heater, the RTGH-95DVLN is a fraction of the standard heater tank.

At 18.5 x 9.8 x 27.5 inches, this heater is compact enough to be squeezed in the tiniest of places.

You can hide it in a closet or any other small place in your house and still enjoy enough hot water to run your entire household.

The modern, clean design also makes it easy to blend the heater with your décor.

Click here to buy it on Amazon.

3. Takagi T-KJr2-IN-NG

Takagi T-KJr2-IN-NG

The Takagi T-KJr2-IN-NG is ideal for apartments and small homes where hot water demand is not as high. This is the smallest heater made by Takagi.

Despite its small size, this tankless water heater will provide enough water for a family of 3-5 effortlessly.

At its best, the heater can produce up to 6.6 gallons of water every minute.

The fact that it is reasonably priced compared to others on this list makes it a perfect buy if yours is a tight budget.

This Takagi heater is also energy efficient, making it environmentally friendly.

The manufacturer offers a ten-year warranty so you can exchange your heater if it doesn’t deliver as promised.

Also Read: How Does A Tankless Water Heater Work?

Parts are guaranteed for five years, so you can be sure that this is a quality piece that will provide exemplary service for many years to come.

Click here to buy it on Amazon.

4. Rinnai RUC98iP

Rinnai RUC98iP

This is yet another Rinnai creation that features in the list of best gas tankless water heaters. Unlike the RUC98iN that uses natural gas, this model runs on propane.

The heater comes in a metallic finish that will fit anywhere in your house.

Additionally, the heater comes without NOx emissions making it great for the environment.

Other notable features include an energy factor of up to 0.96, a maximum BTU of 199,000, sleek modern design.

The heater comes with both concentric and PVC venting options, so it will easily fit in your home, whichever your venting type.

The manufacturer offers a 12-year guarantee of the heat exchanger, so you can expect your heater to serve you well for many years.

In addition, there is a 5-year warranty on parts and a 1-year labor guarantee with the option of extending it to five years.

Click here to buy it on Amazon

5. Noritz NRC661-DV-NG

Noritz NRC661-DV-NG
Noritz NRC661-DV-NG

Noritz is another reputable brand known for its highly efficient water heaters.

The Noritz NRC661-DV-NG is among the most advanced tankless water heaters and the best value for your money.

This heater will effortlessly provide enough hot water in a two-bathroom home.

The fact that it is reasonably priced makes it ideal for those looking for budget natural gas tankless water heaters.

The Noritz NRC661-DV-NG is compact and measures 6.7″ x 13.8″ x 23.6″. The maximum capacity is 6.6 gallons every minute.

This means that you will get enough hot water to run two showers simultaneously, or take a hot shower as the washing machine runs.

This heater can be installed using a standard 40 PVC pipe for a vent. Installation steps are clear, and any handyman can have it up and running in no time at all.

The Noritz NRC661-DV-NG comes with a 12-year warranty.

Click here to buy it on Amazon.

Best Gas Tankless Water Heaters Buyer Guide

If you are looking to buy the best gas tankless water heater for your home, below are some features to consider.

Household size/Needs

A two bedroomed apartment will have a different GPM output when compared to a four-bedroom house.

If your home has only one bathroom, there is no need to invest in a heater that can simultaneously run multiple bathrooms.

The amount of hot water a heater produces depends on its power.

Your heater power of choice should be able to deliver enough hot water to match your expectations.

For a small house, 10,000 BTUs are adequate. Commercial establishments may require power of up to1,000,000 BTUs.

Flow Rate

While the power ensures that you get water at the right temperature, the flow rate will determine the amount of water you get in your hot water taps.

To determine the proper flow rate for your household, consider the number of devices you want to connect to the heater.

For example, if you want to supply all water-based appliances, you are better with a water heater with 9.0 GPM.

For a single hot water faucet, a 1 GPM flow rate is adequate.


Venting is essential for both tank and tankless water heaters.

A sound venting system ensures that hazardous gases are eliminated from your property.

With a proper venting system, you can also get additional intake from the outside whenever necessary.

The best gas tankless water heaters have two venting points that include:

Direct Venting – this Venting needs an exhaust and intake pipe.

The venting pipe eliminates carbon monoxide, among other hazardous gases, while the intake pipe ensures sufficient air intake for your gas tankless heater.

Power Venting – This Venting necessitates an exhaust pipe and a fresh air circuit.


The energy factor will help you calculate the heater’s energy efficiency and cost of operation. Most water heaters come with the energy factor listed.

A quick look at the product description will let you know how much energy is required to optimally run your unit.

Condensing vs. Non-Condensing

Condensing gas tankless heaters are more energy-efficient and easier to install when compared to the non-condensing varieties.

Also, you can use PVC in place of metal with the condensing water heaters.

The non-condensing varieties, on the other hand, are ideal for outdoor placement. They tend to be smaller, cheaper, and perfect for cabins, camping, and mobile homes.


The best tankless water heaters are not necessarily the most expensive. You can get the perfect unit for your home at a reasonable price.

A heater that is powerful enough to service multiple appliances at the same time will cost more than a small, less powerful unit.

Have your home needs in mind and then narrow your search to gas tankless water heaters within your budget.

How to Size Your Gas Tankless Water Heater?

As highlighted above, it is important to ensure that you get a water heater that will meet your home needs in the present and hear future. (Source)

To properly size your water heater, consider the temperature rise and flow rate.

Temperature Rise

Consider the normal water temperature and the output level you desire. On average, tap water gets to about 50F, and most homeowners are looking for water heaters that can raise this level to 115 degrees.

You need to ensure that the heater you choose is strong enough to heat your water to the additional 55 degrees. A less powerful heater will only slightly raise the temperature, and you will often not get the results that you are looking for.

When it comes to temperature rise, you should never compromise. Doing so will only mean that you have to endure lukewarm baths and water that is not hot enough for your other appliances.

Final Thoughts on Best Gas Tankless Water Heaters

Now you have an idea on the best gas tankless water heaters in the market and some of the features that make them stand out.

If you intend to buy one in the near future, you may want to consider any of the options listed above.

Do not forget to take your needs into account when selecting a unit for your home, as highlighted in the buying guide.

You may need to pay a little more for a powerful gas water heater, but considering these can last up to 30 years, you want a unit that will meet your present and future needs.

If you’re yet to decide the best option, then we’d recommend GASLAND Outdoors BS158