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

Read more about best RV tankless water heaters here.

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 This Takagi unit may be the smallest tankless water heater manufactured by this company, but the power makes up for the small size. It’s not the lightest unit – since it weights approximately 38lbs – but it is the smallest by dimension. This unit has a water flow of 6.6 gallons/minute and unlike other units, this is sold as a residential unit only.
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.

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.

Rinnai RL94iP – Great Extension for Commercial Use This Rinnai unit is an outdoor unit that can run 5 plumbing and appliance outlets simultaneously. It maintains a 9.4 gallons/minute flow – the 2nd highest GPM on this list per user manuals.

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.

Takagi T-H3-DV-P – Most Powerful GPM Flow with Ultra-Low NOx Flow This Takagi model is the second heaviest unit on this list – for good reason! It maintains the strongest water pressure at 10 gallons/minute and has water temperatures that are said to go up to 180C (365F).

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.

Takagi T-KJr2-OS-NG – Remote Control for Easy Temperature Adjustment This Takagi model runs on propane and is intended for outdoor installation only. It weighs an average of 38lbs and has a flow of 6.6 gallons/minute.

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.

Rinnai RUC98iN Ultra Series – Largest Unit for both Commercial and Residential Use This Rinnai unit is an indoor powerhouse. It is the heaviest unit on this list which supports an advertised 9.8 gallons/minute flow – tying for the second highest GPM reviewed here. It runs on natural gas and is the second unit that is certified Ultra-low NOx emission.

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

Best outdoor tanklesswater heater

Camplux 5L Outdoor Portable Propane Tankless Water Heater This outdoor, mountable unit is just the piece if you want hot water on your next camping trip. Designed to hook up to a hose, this unit is only 11lbs. It heats water via a propane system and has a water pressure of 1.2 gallons/minute.
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.

Rheem RTG-64XLP – Requires No Minimum Water Level This Rheem unit is an outdoor unit that runs off of propane. At 54lbs, this is one of the heavier units on this list. It is moderately-priced and has an overall customer rating of 4.5 stars.
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.

Rinnai V65EP – Top Performance & Certified for Mobile Home Install This unit is a multi-purpose powerhouse. It is an outside unit which is designed to run off of either natural gas or propane. Rinnai V65EP is also certified to install in mobile homes. It weighs 48lbs and has a max water temperature of 140F. As a safety feature, it has with a temperature lock to prevent accidental changes to water temperature and the water temperature can be set as low as 98F if that is something you and/or your family prefer.

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.

CAMPLUX Enjoy Outdoor Life BD264 – Quickest Model to Assemble This outdoor tankless water heater comes ready to connect to a water source. It weighs 38lbs and is slightly larger and more powerful than its smaller counterpart (See Tank #2). It averages 2.6 gallons/minute and can maintain a water temperature between 85F – 130F (depending on flow).
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.