Reviews of The Best Propane Tankless Water Heaters of 2019

You’ve stumbled across the ultimate resource to help you choose the best tankless propane water heater for your home and needs! 

As homeowners and experts in home water quality products we’ve reviewed hundreds of water and energy products over the years. Our unbiased reviews are designed to help homeowners invest wisely in the right solution for their needs. 

The US Dept of Energy outlines and implements both standards and procedures for energy-efficiency compliance by manufacturers. We’ve taken those standards into consideration along with a few of our own, read on and check out our propane tankless water heater reviews!

  • Freeze Protection
  • Low Carbon Emissions
  • Digital/Wi-Fi controls
  • Leak Detection
  • Low Carbon Emissions
  • Digital Remote
  • Dignostic Controls
  • Digital Remote
  • Overheat Protection
  • Water and Exhaust Temperature Control
  • Ion Flame Failure Protection
  • Manifold Auto-Protection
  • Over Water Pressure Protection
  • Manifold Auto Protection
  • Ion Flame Protection
  • Water Pressure Protection
  • Anti-Freeze Protection
  • Low NOx Emissions
  • LCD Temperature Display
  • CSA-Approved Gas Regulator
  • Flame Failure Protection
  • Freeze Protection

Key Criteria For Our Propane Tankless Water Heater Review

  • UEF: Uniform Energy Factor. Established June 12, 2017 as a universal standard, this is a metric for measuring energy efficiency. The higher the UEF, the more savings for you on your energy bill.
  • GPM: Gallons Per Minute, a measure of your water heater’s delivery Capacity. It’s the most critical decisioning factor that reflects the power of your water heater to deliver a constant flow across multiple rooms. GPM can vary, slowing as the temperature increases. Anything over 5.0 GPM, however, is above the standard.
  • Warranty: A propane-powered tankless water heater should be backed by a guarantee. If the manufacturer won’t stand behind the product, why should we?
  • Safety Features: Temperature controls, freeze protection, and low carbon emissions are additional features that impact both price and quality.

You’ll find a detailed review of each of our selections if you scroll below the table of our 8 top picks.

All of the tankless propane water heaters on our list were chosen by our inhouse team. 

iWaterPurificaton Top Propane Tankless Water Heater Picks

Best Suited For: Large, 2 -3 bathroom home, indoor use only

Product Overview

We begin our review with a powerhouse model from Rheem. The RTGH Direct Vent Propane Tankless Water Heater simply tops all others on our list for quality, performance (GPM), safety features, and its warranty coverage.

This compact unit is easily installed, minimizes cold water bursts to provide a continuous flow of hot water while remaining energy efficient. Once installed, activate the water savings setting to start saving on water flow and your heating bill. Designed for larger homes, Its industry leading low flow activation means you’ll enjoy a hot shower even when supply is low in your area. 

Powerful enough to heat your entire home, Rheem’s propane water heater will last for years thanks to a 12 year warranty and some convenient digital features. Connect remotely to your tankless Rheem unit with the EcoNet app. The self-diagnostic system monitors the efficiency and performance of your tankless water heater, and includes a digital remote as well. 

Its low-emissions design also means less propane fumes.

Features include:

  • Up to .93 UEF (US)
  • 9.5 GPM Max
  • Serves up to 4 bathrooms
  • Self-diagnostic system for ease of maintenance
  • Stainless steel condensing heat exchanger
  • EcoNet Enabled
  • ½ inch gas line compatibility extends up to 24ft
  • Freeze protection up to – 30 degrees F
  • 34 kg
  • 12 year warranty



Awesome safety features

Expect 15 – 20 second lag in hot water temperature 

High energy efficiency

Requires periodic descaling for max efficiency

Low carbon emissions

Powerful 9.5 GPM provides limitless water supply

12 year warranty

Best Suited For:  mid-sized, 1 -2 bathroom home, indoor only

Product Overview

World-class manufacturer Rinnai has created a powerful and energy efficient machine with their V75IP 7.5 GPM Indoor Low NOx model. 

This ultra-low emissions indoor tankless water heater by Rinnai ranks second in our review behind the Rheem because of its slightly lower energy efficiency rating. At 0.81 UEF, it’s still highly efficient, mind you, but better suited for small to mid-sized families, or 2 bathroom homes max.

The Rinnai model is a bit loud but its carbon dioxide emission levels are extremely low. Ventilation is required for indoor use, but installation is easy. There are warranties to cover labor, parts, and the heat exchanger, which really shows confidence in the quality of their tankless units.

  • 0.81UEF
  • 7.5 GPM Max
  • 45.6 lbs (20.7kg)
  • ½ inch Gas line compatible
  • High altitude approved for up to 10,200 ft( 3109 m)
  • AHRI and CSA approved¾ inch inlet and outlet for water
  • Ultra Low Nox for extremely low carbon emissions
  • Leak detection
  • Wi-fi digital remote
  • Temperature range with controllers: 98ºF – 140ºF
  • mobile home installation
  • 1 yr warranty on labor, 5 year warranty on parts 10 YR warranty on heat exchanger



Great safety features

Direct Ventilation Kit must be purchased separately

Warranty covers parts, labor and heat exchanger

Can be a little loud

Energy efficient

Ultra low carbon emissions

Best Suited For: 1 – 2 bathroom home, outdoor unit

Product Overview

If you’re looking for an economically-priced outdoor water heater with a high energy rating, Eccotemp makes some of the best tankless models out there!

Eccotemp’s outdoor liquid propane-powered N45H-LP is another tankless water heater that compares well to other brands in terms of its efficiency. With an 80% energy rating and 6.8 GPM, the N45H-LP is ideal for small households, or 1 – 2 bathroom homes.

You’ll finally be able to enjoy an uninterrupted supply of hot water while the N45H works away. Installation is easy and its compact size means it can be mounted on any outdoor wall close to the water and gas inlets.

  • 0.80 UEF
  • 38 lbs
  • 6.8 GPM max
  • ¾ inch Gas line compatible (¾ inch inlet and outlet for water)
  • Wi-fi digital remote
  • CSA-certified
  • Elevation up to 3000 ft
  • 10 year warranty on heat exchanger, 5 year warranty on parts



High efficiency

Not suited for elevation above 3000 ft

10 yr and 5 yr warranty

No warranty on labor


Wifi control

Best Suited For: Mid-sized, 1 -2 bathroom home, 2 -3 bedroom apartment

Product Overview

Slightly more powerful than the propane-fueled Takagi T-KJr2, the TK4 Indoor Tankless is designed for residential use in mid-sized homes or 2 -3 bedroom apartments. 

The Takagi T -K4-IN-LP provides a pretty impressive 8 GPM and can serve a 2-3 bathroom home with a constant flow of hot water. At just under 35 lbs, its compact size and weight means you’ll save a lot of space. We also like that it includes a number of safety features to prevent against overheating, freezing, as well as temperature controls.

We should warn you, however, that Takagi does not offer a warranty for their tankless propane heater. Several reviews have expressed dissatisfaction with the poor quality of customer service, and defective units are rarely replaced without exhaustive effort on your part.

  • 0.82 UEF
  • 8.0 GPM Max
  • 34.6 lbs
  • Air Fuel Ratio sensor
  • Water and Exhaust Temperature Safety Control
  • Temperature control systems
  • Overheat Cut-off Fuse
  • Freeze-Protection System
  • Manual reset high-limit switch
  • ¾ inch Hot/Cold Water Line Compatible
  • ¾ inch Gas Line Compatible 



Plenty of awesome safety features

No warranty

High energy efficiency

Poor customer service

Best Suited For: 1  bathroom home, single bathroom apartment

Product Overview

No pilot light, no electrical hook-up, this liquid propane tankless water heater will reduce your gas bill and supply you with continuous hot water whenever you need it! 

Ranked 5th in our review, the TC-Home 4.8 has an 18 litre/mn capacity and an energy efficiency rating of 80% which is great. While the GPM is much lower than the other more expensive models, it’s priced economically and works best for a single bathroom home or apartment.

Sadly, the TC-HOME 4.8GPM is not covered by warranty. Tengchang doesn’t have a glowing reputation for customer service, but defects are rare. 

If you already have a water tank but want to install something smaller specifically for use in a single bathroom, the TC 4.8GPM is fairly easy to install and low maintenance. 

Features include:

  • 0.8 UEF
  • 4.8 GPM
  • 18 L/mn capacity
  • ½ inch Gas Line compatible
  • Auto-ignition (Batteries Required ( 2 ‘D’)
  • Flame failure protection



Energy efficient

No warranty

18L/mn capacity heats water quickly

Good safety features

Portable, lightweight

Best Suited For: Single bath home or apartment

Product Overview

For those of you who aren’t fussy about GPM’s and just want an affordable alternative to your existing water tank, we decided to include the TC Propane Tankless Water Heater.

As you may have noticed by now, Tengchang is known for economically-priced gas and propane water heaters that are energy efficient but low on GPM. The TC 2.6GPM delivers the same of what you’d expect from Tengchang.

Designed for use in single bath households, this indoor unit is also fairly easy to install but doesn’t provide the safety features we like. Temperature control is also difficult to adjust but has a range between 8 degrees and 45 degrees F. 

The energy efficiency is rated 80% so you’ll definitely save on your gas bill. Its low GPM of only 2.6, however, makes it significantly less powerful. If saving on gas is your primary concern and you plan on only using it for baths, the Tengchang Propane Gas Tankless Heater should work for you.

We should mention that, once again, Tengchang Propane Gas Tankless Water Heater, is made in China, and is not covered by warranty.

Features include:

  • 2.6 GPM 
  • >0.80 UEF
  • 9.5mm 3/8″ Gas Line inlet
  • Gas pipeline (outer diameter): 20mm rubber gas hose
  • Water Inlet: G1/2”
  • Water Outlet: G1/2”



Energy efficient

Limited application



Instant, continuous hot water

No warranty