Best propane tankless water heater: finding the best choice
Tankless water heaters are a cost and energy effective alternative to traditional water heaters. They are versatile, compact, and powerful which provides both residential and commercial shoppers with plenty of options.
To help breakdown some of the best models on the market, here is a list of 10 tankless water heaters.
Outdoor tankless water heaters
Indoor tankless water heaters
Shot Descriptions
- Takagi T-KJr2-IN-LP – Takagi’s Smallest Unit
- Camplux 5L Outdoor Portable Propane Tankless Water Heater – Least Expensive Tankless Unit
- Rheem RTG-64XLP – Requires No Minimum Water Level
- Takagi T-KJr2-IN-NG Indoor Tankless Water Heater – Excellent at Maintaining Water Pressure
- Rinnai V65EP – Top Performance & Certified for Mobile Home Install
- CAMPLUX Enjoy Outdoor Life BD264 – Quickest Model to Assemble
- Rinnai RL94iP – Great Extension for Commercial Use
- Takagi T-H3-DV-P – Most Powerful GPM Flow with Ultra-Low NOx Flow
- Takagi T-KJr2-OS-NG – Remote Control for Easy Temperature Adjustment
- Rinnai RUC98iN Ultra Series – Largest Unit for both Commercial and Residential Use
Quick Comparison Table
Item model | Size, Weight, Usage | Voltage | Max flow | Warranty |
---|---|---|---|---|
Takagi T-KJr2-IN-LP![]() Check the price | 6.7" x 13.8" x 20.3", 38 lbs, Indoor | 115 volts | 6.6 GPM | 10 year heat exchanger and 5 year parts |
Camplux 5L![]() Check the price | 11.4 x 5.5 x 14.6", 10.8 lbs, Outdoor | 2 Lithium-ion batteries 3 volts | 1.32 GPM | No data |
Rheem RTG-64XLP![]() Check the price | 14" x 10" x 26", 54 lbs, Outdoor | 110 volts | 6.4 GPM | No data |
Takagi T-KJr2-IN-NG![]() Check the price | 6.7" x 13.8" x 20.3", 38 lbs, Indoor | 110 volts | 6.6 GPM | 10 year heat exchanger and 5 year parts |
Rinnai V65EP![]() Check the price | 9" x 14" x 23", 47.8 lbs, Outdoor | 120 volts | 6.6 GPM | 10-year limited |
CAMPLUX Enjoy Outdoor Life BD264 ![]() Check the price | 27.9" x 9.5" x 15.4", 23.2 lbs, Outdoor | 3 volts | 2.64 GPM | No data |
Rinnai RL94iP![]() Check the price | 9.3" x 14" x 23" 26.9 lbs, Indoor | 115 volts | 9.4 GPM | 12 year heat exchanger and 5 year parts |
Takagi T-H3-DV-P![]() Check the price | 11.2" x 17.8" x 24.9", 66 lbs, Indoor | 120 volts | 10 GPM | No data |
Takagi T-KJr2-OS-NG![]() Check the price | 6.7" x 13.8" x 20.5" 38 lbs, Indoor | 120 volts | 6.6 GPM | 12 year heat exchanger and 5 year parts |
Rinnai RUC98iN Ultra Series ![]() Check the price | 10" x 18.5" x 26" 82 lbs, Indoor | 120 volts | 9.8 GPM | 12 year heat exchanger and 5 year parts |
Best indoor tankless water heater
Takagi T-KJr2-IN-LP tankless water heater
A benefit of this unit is that it can use either propane or natural gas to heat water. The factory-default setting is natural gas. Changing it over to propane may require some change in lines, but it can be done by a professional plumber with minimal difficulty.
Many customer reviews assure potential buyers that this is more than adequate for a household. Comments even reference using multiple things at once (e.g. a dishwasher and a shower), without seeing a change in water heat or pressure. However, for those living at higher altitudes, there are certain pressure settings that may need to be adjusted in order to maintain a steady water flow and temperature.
- Small size
- Easy installation
- Maintain performance with multiple water outlets running simultaneously
- Different altitudes impact unit performance
- Venting and valves required for install, but not included in initial purchase
- Propane setting is not intuitive
- Noisy
Takagi T-KJr2-IN-NG Indoor Tankless Water Heater
This Takagi unit – unlike similar models on this list – is made for indoor installation. It weighs just 38lbs and is one of the lighter units in this selection. It runs off of natural gas and can maintain water at a 6.6 gallons/minute rate, a fairly standard water pressure.
One benefit to this unit is that the installation manual is highly detailed. There were a number of customers who were able to install this themselves and saved technician costs. However, it is important to note that many manufacturers will not honor a warranty unless a unit is installed by a factory-certified technician.
This unit is recommended for the impressive water flow. It maintains 6 gallons/minute and can support a number of things at once (e.g. dishwasher, sink and shower). Additionally, since it uses natural gas the cost for many users is noticeably less. Customers also recommend purchasing a Webstone Heater Service Valve Kit to help with self-servicing the machine down the road. This will increase the overall life of the unit.
- Excellent user manual
- Lowers average gas usage
- Supports an average family

This unit weighs just 27lbs and is the second lightest unit reviewed here. As a residential unit, the water temperature goes up to 140F. However, a commercial controller can be purchased separately which allows water temperatures to go up to 185F. With this addition, this unit is a cost-effective option that is perfect if you’re a small business owner in need of a water heater.
There are only a few reasons this unit is not highly recommended and none of them have anything to do with how the unit actually functions. The first reason this is not recommend is because of the awful customer service provided by Rinnai. The company sits with a B- rating from the BBB and most of the complaints registered are related to warranty issues which is the second reason why this is not recommended.
The warranty language is intentionally vague, and the company seems to take advantage of that at the loss of their customers. In addition, the unit must be registered for the warranty coverage within 30 days – a hard deadline that many customer comments said was adhered to without exception. Lastly, there are a number of customers who received a poorly packaged, often scratched or dented unit.
- Digital controller with error code readout
- Additional commercial controller and add temps up to 185F
- 12 year warranty
- Good Manual
- Quiet

Takagi T-H3-DV-P is an indoor unit and is perfect for small restaurants and businesses. It can run 5 water outlet sources simultaneously if the inlet water temperature is not too cold; colder inlet temps will decrease this to 3 sources, which is still more power than most units reviewed here!
Not only is this unit powerful, it also is a certified Ultra-low NOx performer. This makes it even more energy-efficient than other Low NOx units on this list. A standard NOx will reduce emission by .82. This Ultra-Low NOx unit reduces emissions by an impressive .92.
This unit is recommended for its performance and durability. It’s a quiet unit – perfect for a restaurant – and energy efficient. It is digital as well which means there is no pilot light to go out. The only detraction is that the unit sometimes arrives in poor condition due to cheap packaging and the inlet water temperatures will sometimes impact the output temperature and pressure. Overall though, this is reviewed as a top-performing unit.
- Highest GPM
- Certified Ultra-Low NOx flow
- No pilot light
- Computerized safety features

The most noticeable feature of this unit is the ability to adjust the base water temperature using a remote control. In regards to the rest of this, it is a fairly standard unit, both in size, GPM flow and cost.
There are a few quirks that keep this unit from being highly recommended. One of these is the 6.6 GPM flow is only in ratio to the inlet water temperature and flow; the colder the inlet water, the cooler the output water will be. Additionally, for being an outdoor unit, it does not function well in cold temperatures (New York was an example given by a customer). Additionally, it is not built to withstand weather as well as other units and must be protected from rain in order to prevent damage.
If properly installed with extra attention to the outdoor temperature and climate, this unit should run without a problem. It comes with a 12-year warranty coverage on the heat exchanger, 5-year warranty on parts, and a year warranty on labor.
- 12 year warranty
- Remote Control can adjust base water temp

Despite the heavy weight, the unit dimensions are relatively small. This unit is ideal for commercial use, but can also be used residentially if you’re willing to make a bit of an investment. A unique feature of this unit is the concentric piping. This is for ventilation purposes and also helps to decrease the overall space required by the unit.
Just a few things to note in regards to less-than-optimal performance: Water does take time to get hot and needs to run several seconds before temperatures go up.
For water-conscious users, this is a detraction. Also, replacement parts, if/when needed, are not always shipped correctly and are occasionally on backorder.
Overall this unit is well-worth the investment. It is recommended for efficiency and overall performance. In addition, the ability to extend the warranty coverage is ideal if it’s going to have above-average use (e.g. if purchased for commercial use). Useful links: Best golf laser rangefinder Best tire inflator with gauge
- Can be used residentially and commercially
- Ultra-Low NOx emission
- Extended warranty on labor (optional)
- Poor customer service
- Replacement parts – when needed – are often shipped incorrectly or are out of stock
- Water takes a noticeable time to get hot
Best outdoor tanklesswater heater
Camplux 5L Outdoor Portable Propane Tankless Water Heater
Not only is this unit portable, it has a detachable shower head much like certain residential showers. As an added bonus, this shower head can be removed entirely if you want to connect the water heater to a faucet. In addition, there is anti-freezing protection and a flame failure device built into the unit.
It is worth noting, that the water temperature cannot be adjusted. Also, if you remove the shower head and connect it to a faucet, the faucet cannot be an ‘energy saving’ model or the water pressure will be thrown off/stop. Overall, these are minor cons to this unit. As a whole, it is recommended for its ease of use, overall small size, and water-handling capability.
- Low water pressure start-up
- Anti-freezing protection
- Folding handles for easy transport
- Portable propane tankless water heater

One desirable feature is that there is no minimum water requirement. Other units have an auto-trigger that will turn the heater off if the water flow dips below a certain point. This can be very undesirable if you’re mid-shower and this happens. This Rheem unit ensures that doesn’t happen by keeping the heater on regardless of the water level. Additionally, this unit is a certified Low NOx emission.
While it has attractive features, there are a few things to weigh in the balance. The exterior install kit is not included in the purchase of the unit and costs an additional $200. Additionally, there is danger of scale buildup if you don’t have/use a water softener. Aside from that, the water filter requires yearly cleaning and the unit as a whole isn’t too durable.
- Doesn’t turn off heat when water level is low
- Low NOx emission
- Well-detailed instructions
- Low propane consumption

Not only is this unit certified for mobile home installation, it is also a certified low NOx unit. It releases a reduced rate of Nitrogen Oxides (NOx) and Carbon Dioxide which is safer for your home – especially if this unit is being purchased for installation in a smaller square footage area.
One of the best features of this propane tankless water heater is the enhanced scale detection system that is built into this model. It allows for earlier detection of possible scale buildup which protects the unit and allows it to function longer. Additionally, Rinnai provides a capacity calculation and confirms this will run two showers at the same time (assuming the shower heads allow for reasonable, not excessive, flow)
The warranty is another perk to this unit. There is a 10 year warranty on the heat exchanger, 5 year warranty on the parts, and a 1 year warranty on labor. Overall, the only negative feedback from customers (and there were hardly any) related to warranty and installation issues, but none were directed at the quality of the product.
- Auto Scale Detection
- Temp Lock
- 3-part Unit Warranty
- No batteries required

This unit is highly recommended for how easy it is to get up and running. This is ideal for many people who use it camping or who don’t want to leave it out at a summer (or winter) house when they aren’t at the location.
However, this unit is a bit ‘high-maintenance’ and requires some extra care and attention in order to operate well and stay running for a continuous length of time.
This extra maintenance includes:
1. Draining the excess water from the unit if outside temperatures drop to freezing (failure to do so can result in water freezing inside the unit which can cause irreparable damage);
2. Covering the unit properly to ensure rain/wind doesn’t extinguish the pilot light (and thus end your hot water flow);
3. Remove the quick-connect piece that is included. This often detaches and/or leaks easily. Customers found better water flow by connecting it manually to a water source.
- Easy assembly/disassembly
- Gas regulator and Shower kit included
- Batteries required – not included
- Quick-Connect fitting is not reliable
- Wind and Rain will put the pilot light out
- Need to drain residual water out of tank if it is outside in freezing temperatures to avoid the water freezing internally
- Requires at least 3.5gpm to run (not advertised, but in manual)
Placement & Pressure
When looking to purchase a tankless water heater it’s important to know ahead of time where you are going to have it installed (outdoor vs indoor). Many performance issues can be avoided if you consider the outdoor climate and weather conditions when making a selection.
Water pressure requirements are also important to keep in mind. Ask yourself questions like, “How many things will need hot water simultaneously?” and “What type of water flow am I accustomed to?” These questions (and similar ones) will help you determine how many gallons/minute you want to look for in a unit.
Cost
When it comes to tankless water heaters, cost is not always indicative of performance. This is helpful if you’re on a budget because it allows you to select a unit that will function well for you without sacrificing quality. Don’t assume the most expensive unit is the best-performing unit as it may not be the best fit for you.
Additionally, there are almost always additional costs associated with installation – and sometimes ongoing maintenance as well. If you’re trying to be cost-efficient, it may be best to look for a lower-cost unit as the install can sometimes cost several thousand dollars.
Gas vs Propane
The energy source used to heat the water doesn’t directly impact the overall performance of the unit. Propane water heaters are often energy-saving (and cost-saving), which appeals to many consumers.
On the flip side, natural gas water heaters are also energy-saving. If you choose a unit that runs off of natural gas, it’s ideal – especially for indoor units – to choose one that is certified Low NOx emission. Ultra-Low is even better! This will protect your home or business from harmful emissions and it benefits the environment.
Conclusion:
With the advancements in modern technology, a tankless water heater is a highly-comparable alternative to the traditional tank. They are more space efficient, more environmentally friendly, and can reduce water usage because there is no holding tank.
There is less of an initial investment required when purchasing a tankless water heater and it reduces the cost of gas (and toxic emissions) over time. With options for both residential and commercial use, tankless water heaters are well-worth your consideration when it comes time to purchase a water heater.
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