Best Propane Tankless Water Heater Reviews & Buying Guide (2019)


Best Propane Tankless Water Heater Reviews & Buying Guide (2019)

Propane Tankless Water Heater

Liquid propane or lp tankless water heaters are known to be the most powerful fuel type compared to electric and natural gas options.

If you want to get a propane tankless water heater, this is the right place. We have done the hard work for you and spared you hours of trying to figure out what is best option for you.

If you are still unsure whether propane is whats best for your household you should check out our buyers guide and frequently asked questions at the bottom of the page. You can quickly navigate to the questions that you want answers for by clicking on the table of contents.

We go through the benefits of propane tankless water heaters compared to the other fuel types, its disadvantages, how to select the right one for your household and more!

Top 10 Best Propane Tankless Water Heater

Our tech team invested countless hours in gathering customer feedback and assessing verified purchase reviews from some of the most trustworthy brands and models and have narrowed down what we believe are the top 10 best propane tankless water heaters.

No matter what size household you have and whether you need a propane tankless water heater located indoors or outdoors for either a single point of use, multi point of use or for your whole house we have endeavoured to provide options for everyone!

Name Rating Prices Application Location
Bosch 830 ES LP


4.8 out of 5 stars (4.8 / 5)

Read Reviews



Whole Indoor
Camplux Pro 26L 6.86 4 out of 5 stars (4 / 5)

Read Reviews

CHECK PRICE ON AMAZON Whole house Indoor
Rinnai V65IP 6.6 GPM 4 out of 5 stars (4 / 5)

Read Reviews

Rinnai RL94eP 4.1 out of 5 stars (4.1 / 5)

Read Reviews



Whole House Outdoor
Eccotemp i12-LP 4 out of 5 stars (4 / 5)

Read Reviews



Whole House Indoor
Takagi T-KJr2-IN-NG 4.2 out of 5 stars (4.2 / 5)

Read Reviews



Point of use Indoor
Camplux 5L 1.32 GPM 3.9 out of 5 stars (3.9 / 5)

Read Reviews



Single Point Outdoor
Rheem RTG-84DVP 5 out of 5 stars (5 / 5)

Read Reviews



Whole House Indoor
Rinnai RUC98iN 4.5 out of 5 stars (4.5 / 5)

Read Reviews



Multiple Points Indoor
Camplux 10L Outdoor 4 out of 5 stars (4 / 5)

Read Reviews



Multiple Points Outdoor

Propane Tankless Water Heater Reviews Top 10

In this section we break down the top 10 propane tankless water heater reviews and go through the specifications of each one as well as the pros and cons of each one.

We have also provided a link to Amazon to check current prices as well as read some of the customer reviews after purchasing and using these products.

We will go through the whole house application models first, then single point of use and then our multi point application choice of preference.

Here are our best propane gas water heater reviews.

Whole House Propane Tankless Water Heater Reviews 


Bosch 830 ES LP Therm Tankless Water Heater, Propane

  • Fuel Type: Liquid Propane
  • Application Type: Whole house
  • Location: Indoor
  • Btu: 175,000
  • Gpm: 8.3
  • Energy Efficiency: 83%
  • Size: 11.2 x 17.9 x 30.5 inches
  • Weight: 74pounds
  • Display:  Digital
  • Warranty: 15 years

If you need a powerful tankless water heater to handle various points in the house at the same time, try the Bosch 830 ES LP Therm Tankless. This unit stands out as one of the best propane tankless water heaters as it comes with a unique heat exchanger design, a modulating temperature sensor that limits propane consumption while maintaining the flow of hot water. This is a product of Bosch, one of the leading engineering companies in Germany.

With this water heater, you can get a temperature rise of 35F with an impressive flow rate of 8.3 Gallons per minute. This unit gives as much as 30% saving on propane; hence, more hot water with less propane. Besides, the energy star certification makes you qualify for a rebate from the government.

The unit is meant for indoor installation and can be installed vertically or horizontally. It works with stainless steel vent and pretty easy to install, anywhere in the house. It comes with a whooping warranty period of 15 years, making it one of the top propane tankless water heater brands available. The heat exchanger design of Bosch 830 ES LP Therm Tankless is also patented which gives the ability to get rid of cold water sandwich in the pipe, ensuring you have a pretty long lasting unit.

I am text block. Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

  • Impressive warranty period
  • Electronic ignition system
  • Rebate from the government
  • Antifreeze protection

  • The price is a little on the high side

User Rating:

4.8 out of 5 stars (4.8 / 5)


Camplux Pro 26L 6.86 GPM Outdoor Propane Tankless Water Heater

  • Fuel Type: Liquid Propane
  • Application Type: Whole
  • Location: Indoor
  • Btu: 180,000
  • Gpm: 6.86
  • Voltage: 120Volts
  • Energy Efficiency: 82%
  • Size: 15.6 x 6.5 x 22.6 inches
  • Weight: 49.9 pounds
  • Display:  Digital
  • Warranty: 1 year

If you need an outdoor tankless water heater that runs on propane, Camplux Pro 26L 6.86 GPM is the right choice. It comes with a compact design and an impressive flow rate of 6.86. It is a whole house unit with the ability to serve more than three points at a time. With an impressive power output of 180,000 BTU/hour, this is your ticket to a continuous supply of hot water without restriction.

There are much water heater available in town. However, what makes Camplux Pro 26L one of the best tankless gas heaters are the impressive safety features. Hence, you will have access to antifreeze protection, flame failure device, overhanging protection, etc., all to ensure that you are safe. There is a digital remote control with which you get to set your desired water output temperature. The device also stands out in that it is easy to use and convenient.

This unit is an output of the JAL group, one of the giant household industries noted for outstanding features. Hence, with this product, you are sure of getting portability, energy saving feature, and innovation. Also, camplux prides itself as a product with the most advanced technology in heating water. Hence, you can get up to 50% saving on water cost

  • Impressive safety features
  • Comes with a remote control
  • The capacity of 50% saving on your energy bills
  • Simple and compact design

  • Self-installation could void the warranty

User Rating:

4 out of 5 stars (4 / 5)


Rinnai V65IP 6.6 GPM Indoor Low NOx Tankless Propane Water Heater

  • Fuel Type: Propane
  • Application Type: Whole house
  • Location: Indoor
  • Btu: 150,000
  • Gpm: 6.6
  • Energy Efficiency:
  • Size: 13.9 x 8.8 x 23.6 inches
  • Weight: 49.6 pounds
  • Display: Digital
  • Warranty: 10-Year Warranty on Heat Exchanger, 5 Year Parts

This is a discrete and compact appliance that can be fitted anywhere in the house for a continuous supply of hot water. This is your ticket to constant supply of clean and reliable hot water. If you need a water heater for shower, dishwashing, and laundry, this is the ideal choice.

This is one of the top energy efficient indoor propane tankless water heaters with minimum demand on energy. It is pretty simple to operate and comes with an LCD screen with which you can set it to the desired temperature. This is an energy efficient unit that can allow you to save money in the long run. With this device, you can get an output water temperature of 98F to 140F.

There is also a temperature lock that prevents the unintended temperature shift. Hence, you get to a supply of water at the predetermined temperature. If you live in a place with hard water, this is the best option for you.

  • Does not take much space The LCD screen gives you control of the heater A constant supply of hot water Ease of use and installation

  • Some customer reported less than a minute delay before water flows

User Rating: 

4 out of 5 stars (4 / 5)


Rinnai RL94eP Outdoor Propane Tankless Water Heater

  • Fuel Type: Liquid Propane
  • Application Type: Whole house
  • Location: Outdoor
  • Btu: 199,000
  • Gpm: 9.4 gpm
  • Energy Efficiency: 83%
  • Size: 14 x 10 x 23 inches
  • Weight: 44 pounds
  • Display: Digital
  • Warranty: 12 years on heat exchanger, five years on parts

This tankless gas water heater can give you as much as 9.4 gallons of hot water per minute. It is one of the best propane tankless water heater configured to run on a minimal amount of propane to heat water. With this, you get impressive savings on propane year by year as you use the heater. Besides, these materials enjoy a pretty high-quality construction material hence, it will last years to come.

It stands out from other heaters as it has clean valves which other heaters does not have. Besides, it can deliver hot water to heights as high 185 feet. Since it is an outdoor model, it does not require venting hence, reduced overall cost. It is small, compact and configured for wall mounting.

There is a 24-hour programmable controller that gives extra convenience and diagnostics. With this, you get to monitor the temperature quickly and troubleshoot. Also, since this unit enjoys high-quality material, the heat exchanger is made of high-grade copper. This makes this tankless water heater qualify for residential and commercial use.

  • Less demand for energy
  • Suitable for residential and commercial house
  • An extensive warranty period
  • Little demand for propane

  • Installation is pretty technical

User Rating: 

4.1 out of 5 stars (4.1 / 5)


Eccotemp i12-LP Water heater 4 GPM Black

  • Fuel Type: Liquid Propane
  • Application Type: Whole house
  • Location: Indoor
  • Btu: 80,000
  • Gpm: 4 GPM
  • Energy Efficiency: 79%
  • Size: 15 * 24 * 4 inches
  • Weight: 29 pounds
  • Voltage: 120 volts
  • Display: LCD
  • Warranty: 2 years

This distinct tankless water heater comes in a sleek black acrylic glass casing. For everyone who needs a reliable tankless water heater to serve many points at a time, Eccotemp i12-LP is the right choice. It comes with exceptional features making it one of the top choices among users. It comes in a reasonable size which makes it easy to install, besides being user-friendly.

All you need to power this gas heater is a 120Volts power supply which ensures proper functioning. Besides, you can enjoy a sleek and appealing design with the black acrylic glass casing. With a flow rate of 3 GPM, you have enough water supply for the task of an average family. There are a touch screen and LCD feature where you can control and monitor the output water temperature.

The child lock technology gives peace of mind as this ensures that the unit is safe to curious kids. It also features an energy saving mode as well as a safe electronic ignition system. This unit comes with a horizontal stainless steel vent kit which is ready to install.

  • User-friendly manual and a quick installation process
  • Automatic temperature control,
  • Stainless steel construction ensures durability
  • Beautiful appearance

  • Might not produce enough water to serve the house

User Rating: 

4 out of 5 stars (4 / 5)

Single Point of Use Propane Tankless Water Heater Reviews


Takagi T-KJr2-IN-LP Indoor Tankless Water Heater

  • Fuel Type: Propane gas
  • Application Type: Point of Use
  • Location: Indoor
  • Btu: 140,000
  • Gpm: 6.6
  • Voltage: 120 Volts
  • Energy Efficiency: 81%
  • Size: 6.7 x 13.8 x 20.3 inches
  • Weight: 40 pounds
  • Display: Digital
  • Warranty: 10-year heat exchanger and 5 year parts

This is a small, efficient and straightforward tankless heater that runs on liquid propane. It is a silent unit that can handle many showers at a time. This is the best propane tankless water heater to buy if you don’t want to invest much effort into maintenance. This tankless water heater works the same way a natural gas works although, you will need stainless steel for the fumes.

With this tankless water heater, you can get a temperature of 150F and above. This is more than enough to handle showers, dishwashers, and co. There is a switch on the unit that can help you adjust the outlet water temperature on it. The unit also comes with a remote control which adds comfort.

Installation is easy and should only be handled by a trained electrician. There is a detailed guide that can guide you through the installation process if you want to do it yourself. You, however, risk voiding your warranty.

  • Price is pretty affordable
  • Small in size
  • Low noise
  • Temperature setting is easily adjustable with the presence of a remote control

  • Not recommended for large homes
  • There might be flow delays from extensive use.

User Rating: 

4.2 out of 5 stars (4.2 / 5)


Camplux 5L 1.32 GPM Outdoor Portable Propane Tankless Water Heater

  • Fuel Type: Propane
  • Application Type: Single point
  • Location: Outdoor
  • Btu: 340,000 BTU/hour
  • Gpm: 1.32
  • Energy Efficiency:
  • Voltage: 230 Volts
  • Size: 11.4 * 4.3 * 14.8 inches
  • Weight: 14.11 pounds
  • Display: Digital
  • Warranty: 1 year

If you need a portable propane tankless water heater for camping, vacation, cabins, beach house, etc., Camplux 5L 1.32 GPM is the right choice. While it is intended for outdoor installation, it can be installed indoors with oxygen depletion sensor protection. The sensors are powered by 2 D cell batteries where electricity is unavailable. It is an output of the JAGAL group, a brand well known for innovation portability and energy saving.

This unit employs an advanced saving technology that saves both water and gas. Hence, you can enjoy a considerable saving on your water bills with Camplux 5L 1.32 GPM. It is compact and capable of 114.8F temperature rise. With its small size, moving around is easy which enables it to fit for outdoor installation. The unit also comes with impressive safety features, making it one of the top outdoor tankless water heater. There is the oxygen depletion safety shut off valve, antifreeze protection, flame failure device and overheat protection, and all meant to keep you save and your device in top condition.

With this best propane water heater, you can wash your car, wash your dog or boat and many other things around the house. With the 2D cell ignition system, it is suitable for places without electricity

  • Battery powered, ideal for use in the absence of electricity
  • Impressive safety features
  • Compact and portable
  • Remarkable saving on fuel and water

  • Not suitable for drinking water

User Rating: 

4 out of 5 stars (4 / 5)


Rheem RTGH-84DVLP Indoor Direct Vent Liquid Propane Condensing Tankless Water Heater (h3)

  • Fuel Type: Liquid Propane
  • Application Type: Whole House
  • Location: Indoor
  • Btu: 157,000
  • Gpm: 8.4gpm
  • Energy Efficiency: 82%
  • Size: 9.8*18.5*27.5 inches
  • Weight: 76.9 pounds
  • Display: Digital
  • Warranty: 5 years on parts, 12 years on the heat exchanger.

The next on the series of our top-rated propane tankless water heater is Rheem RTGH-84DVLP. It is an indoor tankless water heater powered by liquid propane. It is one of the best rated tankless water heater powered by propane with many high-end features that make it stand out on the list. This gas heater is energy saving and can serve two bathrooms in cold climate and three bathrooms in warm climates.

It comes with an effective water-saving option in which homeowners get to save as much as 1100 gallons of water per year. This happens because the unit limits water to flow through the pipe until you have the preset temperature.  Everything you need for an easy and swift installation process comes with this unit. Besides, there is also a feature that alerts users on the need for maintenance, making it a pretty safe and sophisticated unit.

There is a remote control with which you can set the preferred water temperature within 10 feet of the unit. The impressive safety feature of Rheem RTGH-84DVLP guards against extreme temperature as well as freeze protection.

  • Good safety features such as the freeze protection
  • Environmentally friendly
  • Intelligent unit
  • Space saving

  • Extra installation accessory cost

User Rating: 

5 out of 5 stars (5 / 5)


Rinnai RUC98iP Ultra Series Tankless Water Heater

  • Fuel Type: Liquid Propane
  • Application Type: Multiple points
  • Location: Indoor
  • Btu: 199,000
  • Gpm: 9.8 GPM
  • Volts: 120 volts
  • Energy Efficiency: 96%
  • Size: 10*18.5*26 inches
  • Weight: 82 pounds
  • Display: Digital
  • Warranty: 12 years on heat exchanger, 5 years on part and 1 year on labor

If you need a reliable propane tankless water heater, Rinnai RUC98iP is a good one to consider. This is a product of Rinnai, one of the most trusted brands with almost a century of experience in the field of gas appliance. Hence, you can trust the quality of Rinnai RUC98aP, as many professional bodies also certify it. This unit works with a whopping power input of 199,000 BTU which is adjustable depending on your needs.

With an energy factor of 96%, you can be assured of an impressive saving on your energy bills. It is compact and sleek, but not light in weight. You can control the exit water temperature and also lock the temperature to the desired point. The unit comes with concentric or twin pipe PVC for the venting option. This is a big propane tankless water heater with a big water and gas supply inlet than the most tankless water heater. An electric ignition powers the system and only draws 64Watts of electricity while working.

Not only is this brand a bigger gas heater but a stronger one as well.  With an energy factor of 0.95, it is energy star certified. While it is a big tankless water heater, it can be installed anywhere without much demand on space.

  • Impressive energy saving
  • Energy star certified
  • Two venting options
  • Environmentally friendly
  • Occupies a small area

  • It is heavy
  • Suitable for indoor installation only

User Rating: 

4.7 out of 5 stars (4.7 / 5)

Multipoint Of Use Application Propane Tankless Water Heater Reviews


Camplux 10L Outdoor 2.64GPM Digital Display Portable Propane Gas Tankless Water Heater

  • Fuel Type: Liquid Propane
  • Application Type: Multipoint of Application
  • Location: Outdoor
  • Btu: 68,000
  • Volt: 110V
  • Gpm: 2.64 GPM
  • Energy Efficiency: 88.5%
  • Size: 12.8 * 5.9 * 20.3 inches
  • Weight: 23.8 pounds
  • Display: Digital
  • Warranty: 1

To everyone out there who needs an outdoor water heater that runs on propane, Camplux 10L Outdoor is a good choice. This is a portable outdoor tankless heater which is capable for both summer and winter use. It is a high-class tankless heater that can be adapted for use in both summer and winter, with a high tendency of saving more gas during summer time. It comes with user-friendly controls, superb functions and optimum water utilization efficiency.

This is an environmentally friendly unit with limited exhaust fumes. There are fantastic safety features that make this unit safe around the house. Hence, there will be no case of overheating, alongside an automatic 20 minutes safety device as well as anti-freezing security protection. There is also the energy saving feature which gives an 11.5% reduction in fuel. Also, the unit comes in a compact design, light and portable.

If you need an efficient outdoor tankless water heater for camping trips, vacations and all forms of outdoor activities, this is the best component. It is powered by 2D cell batteries which turn the system on automatically on ignition. This serves as an extra source of power that makes it possible to run the unit even with no propane gas

  • The instant flow of hot water within seconds
  • Users enjoy a reduction of 11.5% on energy
  • User-friendly setting
  • Portable and sleek in design
  • Capable of running on 2D batteries in the absence of propane gas

  • The unit does not come with fluid pipe

User Rating: 

4 out of 5 stars (4 / 5)

Propane Tankless Gas Water Heater Buying Guide & Frequently Asked Questions

Propane and natural gas water heater work with the same principle, the difference is in the source of fuel.

Propane, however, stands out in that it is more efficient in heating water. However, it is more expensive than natural gas — more on the pros and cons of lp on-demand water heater below.

Advantages of Propane gas tankless water heater compared to an electric and natural gas fuel type 

There are many ways that propane water heater stands out compared to the natural gas and electric powered tankless water heater. Some of the strong points of propane type are:

1. High BTU value 

Propane gas tankless water heater provides a high amount of BTU compared to the natural gas and the electric counterpart. For instance, a cubic foot of natural gas gives about 1,000 BTUs. This same value with natural gas gives 2,500 BTU. In other words, propane is 150% useful compared to natural gas. The literal interpretation of this is that you will use a lesser amount of propane to heat water compared to natural gas.

2. Higher Savings 

The primary source of fuel used in the lp gas water heater is propane. Besides, this unit does not store water and heat over and over again. This translates to reduced demands on energy. Hence, the saving on your energy bill is pretty significant.

3, Very Efficient

Besides the high BTU value that comes out from liquid propane gas tankless water heater, this unit heats water much faster than electricity and the natural gas. This makes them pretty efficient for use as whole house unit.

4. Special Rebate From the Government

Due to the efficiency of the gas tankless water heater, the demand for electricity is less. This makes the owner qualify for special financing from the government. With this, you get to offset the high cost of installation.

5. High Flow Rate

One of the strongest points of propane gas tankless water heater is that hot water flows at a pretty high flow rate. This makes it sturdy and capable enough to serve the many fixtures needed in the house.


What are the disadvantages of a propane water heater compared to electric and natural gas? 

Yes, there are many advantages to the propane water heater. However, this does not exclude it from some cons. Here are some of the disadvantages of liquid propane tankless water heater.

1.  It is Costly and Considered More Risky 

Yes, propane is pretty efficient as a source of energy. However, it is a bit more costly compared to other options especially the electric tankless water heaters.

Additionally the issue of safety is the main concern for most people. Propane is a pretty could trigger an explosion if there is leakage and the wrong combination occurs. However, as long as you follow the manufacturer’s guide, and get it installed by a professional, the risk of explosion is extremely low.

2. The Need for Constant Maintenance

Unlike the electric unit that hardly needs an inspection, a propane gas heater needs inspection and maintenance at least once a year. This is important to guard against leaks and also get rid of soot build up from the burner.

3. Setup cost is Costly 

Propane gas tankless water heater is pretty expensive in setting up compared to the electrical unit. This is because some installation requirements like venting make the overall cost build up. There is also the fact that propane is much costly compared to natural gas.

How Much Will a Liquid propane tankless water heater save you?

One of the strong points of tankless water heater is the absence of a tank. This removes the need to store water and to keep heating water to maintain the required temperature. The disadvantage of this is distinct – wasting energy which translates to substantial energy bills. Tankless water heater, on the other hand, does not store water. Instead, running water flows through the heat exchanger where it receives heat and is distributed to the points of usage. This process does not only save water but saves energy. The U.S. Department of Energy estimated that lp gas tankless water heater gives a saving of approximately $108 per year. This is much more than the electric counterpart which offers a saving of about $44 annually.

Another estimation by the Energy Gov website revealed that a typical household uses 64 gallons of water per day. A family will need an average of $500 to heat this amount of water in a year. However, a tankless water heater has an average efficiency of 29%. This means you get to save between $96 – $200 a year depending on the type, capacity, and frequency of use of your propane tankless water heater.


Different Application of Propane Tankless Water Heater

The best propane tankless water heater comes in various types. Hence, if you need something simple to serve multiple points or a unit that can take care of the entire house, this propane water heater review will shed light on it.

Based on the categorization above, we have the following:

1. Single Point of use Application

Are there various points in the house that needs its supply of hot water, a single point of use application is recommended. Hence, if you need hot water supply at a sink, a shower, or the laundry, you can have a single point propane tankless water heater fixed right near the point where it will be needed – under the sink or just behind the shower head.

Single point tankless heaters are usually small and pretty useful. Besides, they reduce heat loss since hot water doesn’t have to travel a very long distance to get to the point where it is needed.

2. Whole House Application 

Propane gas tankless water heater meant for the whole house is recommended if you have a few points in the house that needs a hot water supply. This type of tankless water heater supplies hot water to various points where it is required at the same time. Hence, someone might be having a shower and another person doing the dishes. They both get access to hot water without restriction.

These units are usually expensive but strong enough to handle several points at the same time.

3. Multipoint Application

Multipoint tankless water heaters are effective and recommended for people that use water in a remote location like cloakrooms and garage. They are an efficient unit that can handle showers, tap, and kitchen when needed.


How to Determine the Right Size of Your Liquid Propane Gas Tankless Water Heater 

Liquid propane Tankless water heater is a significant investment which comes in various types. Hence, it is necessary to get the sizing right to prevent having an oversized or undersized unit. Besides, gas fired tankless heater are more efficient than the electric counterpart. There is, however, need for venting to take care of the fuel needs.

Bear in mind that the mode of sizing a tankless water heater differs from how the tank type is done. However, the aim is the same – having your water heater give enough amount of hot water at the required temperature.

Getting a small or oversized unit will give birth to additional issues such as higher running cost, high cost of installation, wasted energy which does not pay you. We have the following guidelines in place to help you determine the right size and capacity of your tankless water heater.

Determine the Mounting Space 

One of the advantages of going to a tankless water heater is the size. Compared to the natural gas counterpart, they are pretty small hence can be installed on the wall. Propane gas tankless water heater must, however, have enough mounting vents to expel the combustion fumes.

Take the Cold Water temperature 

Your incoming water temperature is critical in sizing your tankless water heater. The incoming water temperature will be raised to the desired temperature by your propane heater, which will supply to the required outlet in the home. Hence, when you have an incoming water temperature at 30F and a laundry that uses 70F, your propane tankless heater should be capable of giving you at least 40F temperature rise.

Examine the Flow rates 

One of the factors that determine the efficiency of the propane tankless water heater is the flow rate. A typical low shower head usually uses about 1.5 GPM as well as a sink for doing the dishes. Many modern appliances do have a GPM rating which can be handy in sizing the GPM rating of your gas heater.

Regular propane gas-fired tankless water heater does give a temperature rise of 70F or more when five or more gallons of water is used per minute. Bear in mind that the lesser the amount of water demanded, the higher the temperature of water that can be achieved.

Determine the Tankless Water Heater Size 

Let us assume we have an incoming water temperature at 40F. We want to determine the maximum flow rate of water used. Let us also assume someone is having a shower with water at 1.5 GPM and desired temperature 105F. Another person is taking care of the dishes at 1.5GPM and desired temperature 110F. The laundry is also being used at 120F with a flow rate of 2 GPM.

The entire GPM during this period is 5.0. Hence, you need a propane tankless gas water heater that can maintain the temperature required by the various appliances at the same time. Therefore, your ideal tankless water heater, in this case, is a gas heater that can cause a 70F rise in temperature at 5 GPM.

In sizing your propane tankless water heater, use the following consumption rate with various elements:

  • Shower or bath requires around 20 gallons
  • Showers with the energy efficient shower head – 2.5-3 gal/min.
  • Automatic dishwasher requires around 14 gallons or 1.5 GPM.
  • Washing machine requires 32 gallons to wash the clothes or 2 GPM.
  • For a kitchen sink, you need 1.5 GPM.
  • To shave, you need 2 gallons of hot water.

To determine the size of your propane tankless heater, list all the devices you think you will use at a particular time and sum up the flow rates. For instance, we can assume that a tankless water heater will supply a shower with two sinks simultaneously. If we assume the demand for water at the shower as 2.7 gpm and 0.65 gpm each for the sink, the total peak demand will be 4.0 GPM.

For whole house propane gas unit gives a high-temperature rise and a high flow rate. Your best propane tankless water heater for you should have a flow rate and temperature closer to what you need.

Installing an On-demand propane Tankless Water Heater: How Much Does it Cost? 

On average, it cost around $1,500 to install a propane tankless water heater. This, however, is a factor of the model and labor involved s tankless water heater comes in various brands. A plumber will likely charge at a rate of $45 to $150 for installation.

Labor and the type of heating equipment are the most influential factors that determine the cost. When you hire a professional, you will likely be charged at a flat rate with a final labor cost of around $100 to $450.

You should also factor in the cost of materials for necessary parts. For a propane tankless gas heater, you will need accessories like termination vent kit, gas connector kit, fitting and mounting hardware, and two pieces lead-free brass valve set.


Investing in a propane tankless water heater is a wise investment for families that require high flow rates and extremely fast water heating. In regions where the natural temperature of water are colder then normal a propane tankless water heater should highly be considered.

If the costs are a bit too much to bear then you should check out the natural gas tankless water heater for more options.

Hopefully the above propane tankless water heater reviews with the buying guide has informed you on what decision to make for you and your household!