Best Gas Water Heaters

10 Best Gas Water Heaters (All Category Champions Exposed!)

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This article will reveal the best gas water heaters from each tankless and tank-type category to handle all your requirements. But before I begin,

Do you think using gas instead of electricity is sometimes more reasonable to produce essential household or commercial hot waters?

“Lowering the cost” or “better install-ability at the remote/urban areas” what should be the purpose of using a gas water heater instead of an electric one? How long do they last?

Which one should you choose? Natural gas or LPG? Tankless or Tank type variant? What are all their advantages & Disadvantages?

If you are feeling curious to know, you are welcome, my Friend!!!

I will explain everything to you step by step to satisfy all your curiosity, questions, and confusion. Also will include a list of recommended gas water heaters—the champions from each category.

Jump to Gas Water Heater Review

12 Essential Things to Choose the Best Gas Water Heater


1. Indoor vs. Outdoor Installation – What’s Your Requirement?

Most gas water heater brands manufacture both “Indoor” & “Outdoor” installable models, and both have their Pros & Cons. 

Indoor variants produce hot water “MOST EFFICIENTLY,” and the operation cost is the lowest comparing anything else! Also, they are designed to ensure the highest safety!

But, indoor gas water heaters are expensive. They require ventilation to pass the exhausts as burnt gasses make several toxic elements like CO, CO₂, NOx, etc. No gas appliances are free from emissions. So, you have to become vigilant to keep your indoor air cleaner from invisible presences.

Again, any gas leakage inside your home near the indoor heater installation might be dangerous. 

An Expensive Tips:  Indoor models can be installed outdoors very easily!!! If you do so, that would be something extraordinary, the most efficient, and the safest permanent solution.

On the other hand, Outdoor gas water heaters are comparatively cheap. There’s no worry about emissions or ventilation. Whatever inconvenience would happen that will remain outside! So considering these facilities, these are great.

But they consume more fuel and run with less efficiency. So the operational cost is slightly high. 

So, my great suggestion is, if you have the budget go for an indoor variant and install it outdoor. But keep it under a shed or such a place where heavy rainwater won’t reach.

2. Propane vs. Natural Gas – Which should I Choose?

Of course, Natural Gas should be your first preference! Cause?

The annual operational cost of an 11 GPM natural gas water heater is around $201.

The same 11 GPM propane water heater’s yearly operation cost is about $481.

So, if you have a natural gas pipeline, there’s no need to think twice and straightly should choose the natural gas variant! 

But, there are some exceptional scenarios. Suppose you require the gas water heating system outdoors, inside a travel trailer, campervan, caravan, or remote locations where the natural gas line isn’t available. In that case, you might choose the propane variant, finding no other ways.

And, undoubtedly using propane is less expensive than using electricity, so propane should be your second choice.

3. Tank Type vs. Tankless – Drawbacks of Each Type!

In 95% of cases, tankless gas water is a better choice. Cause,

  • The price tag is almost similar to tank-type.
  • No waste of energy & works most efficiently with a minimum annual operational cost. 
  • Most importantly, instantly unlimited hot water with a proper temperature! 
  • Smaller in size and intelligent operation.

The only drawback of a tankless water heater is, you won’t get a boiling point steaming hot water, and it requires yearly maintenance. Additionally, in winter, the too cold environmental temperature will affect its performance level.

On the other hand, a Tank-type water heater can produce almost steaming hot water, which is sometimes essential for laundry and kitchen tasks. A negative scale winter temperature won’t be able to impact its performance.

But, once you use the whole tank of hot water, you will require an hour-long waiting time to get hot water again.

Another significant disadvantage of the tank-type water heater is the gradual temperature drops when you turn on the hot water tap.

Cause, the cold water enters the same hot water tank through the cold inlet and getting mixed with hot water. So the temperature gets decreased gradually.

Here is a picture to demonstrate this matter.

Gradual Temperature Fall of Tank Type Water Heater.jpg

4. Water Holding Capacity vs. Flow Rate(GPM) – Ensure Exact Demand

Tank-type water heaters are specified by tank size and BTUs. Tankless water heaters are being measured by flow rate called GPM (Gallon Per Minuit). 

You might think the larger, the better but, that’s not always the truth. 

For tankless water heater especially, excessive size means waste of power and increased utility bill. So, here’s a basic calculation to feel your demands.

For Tankless Water Heater.
Around 4 GPM model can handle 2 family members, 1 Bath, Kitchen, & laundry.

Around 6 GPM variants are sufficient for 3 Members, 2-baths, kitchen & laundry. But if you own a luxury bath with large bathtubs & a spa, then choose the 7.5 GPM.

Finally, pick the 11 GPM variant for more than 4+ family members. This variant can handle 3-baths, kitchen, laundry, and everything else you require.

For Tank-Type Water Heater
In this case, you should go for a bigger variant. The 50-gallon unit should be your minimum preference which can handle up to 3 family members. If you have more than 75 gallons will be perfect.

Cause bigger tank-type water heaters will lower your operation cost comparing the smaller ones.

5. How Many Hours The Tank Type Heater Takes to Heat?

Residential tank-type gas water heaters generally contain a lower BTU/hr capability. Depending on BTU & the inlet water temperature, it takes almost 35-45 minutes in regular seasons. But in winter, it may take around an hour or more.

Commercial tank-type water heaters have 3-times more BTUs to perform aggressively. They take around 10-15 minutes to raise the preset temperature.

Note: Should you use commercial models for residential purposes? Obviously NO.

6. Higher Price with Extended Warranty or the Opposite?

It depends on your budget and mentality. Prestigious brands like Rinnai, Rheem, A.O smith charges more, and obviously, they have incredibly excellent quality. Also, they offer an extended warranty and after-sale services.

But, some new brands are also doing very well. Brands like Camplux, FOGATTI are new, but their build quality, performance is mind-blowing and head-to-head comparable with expensive brands. Again, they offer their products at a lower price and marge their human resource expense by lowering the warranty period. But they don’t compromise with their product quality.

Finally, a lower price doesn’t indicate lower quality, and a higher price doesn’t assure an unlimited lifespan.

7. How Frequent It Requires Maintenance!!!

Tankless water heaters require frequent maintenance. Depending on water chemistry, you will need to flush the unit at least once a year. It means cleaning the device with vinegar or some other acidic cleaner.

A tank-type water heater doesn’t require that random maintenance, but you should check the anode rod at least once a year and replace it after 2-3 years or when it’s required.

8. Installation Cost and Complexity

Gas water heaters are complicated machines and slightly tricky to install. Unless a licensed plumber installs the unit, the warranty may void.

Depending on the type of water heater, your water & gas line condition required electrical wirings; installation may take around $500-$1000. 

Sometimes as high as $2000, in case there are more difficulties. But if you get a dealer’s installation service, you should grab their offer!

How about DIY installation? Well, if you are a technical personality, it could be done. In that cases, I would request you to

  • Read the installation manual first.
  • Ensure your required size of water line, gas line; ventilation pipe is ready.
  • A dedicated gas line may be required, don’t attempt to do it unless you have enough confidence.
  • Ensure studying electrical wirings and control panel connections.
  • Finally, connect all lines too carefully, and check, recheck to ensure no gas or water leakage.
  • If you face any difficulty, ask a professional for help.

9. Electric Spark Ignition vs. Standing Pilot – Choose the Reliable One!

If I rank them according to the best to the less good choice, that would be

  • Electric Spark Ignition.
  • Electric Hot Element Ignition. (Rarely found)
  • Electric Piazo light Ignitor.

But, as long as there is an electronic control panel, there’s nothing to be worried about. Cause there remains an electronic security system to work against flame failure, and it works automatically. But, if you choose a spark-ignition variant, that would be long-lasting probably.

10. Anti Freezing Technology

If the inside water of a gas water heaters becomes frozen, internal components will get damaged. So having an anti-freezing system is a must-have element for these devices.

[All the models we’ve enlisted have anti-freezing technology. You may remain worry-free with these.]

Generally, tankless water heaters remain at risk of getting frozen in frigid weather, especially the outdoor variants. 

But, if the electric & gas power remains ON, you will remain trouble-free if your heater has anti frozen system. But it won’t work if the heater remains out of power.

So, in case you leave home for a long trip, don’t forget to winterize your heater.

The risk of getting frozen is very low for the tank-type water heater. Cause the tanks are insulated. But for security, you should winterize it too if you leave home for a trip.

11. Does it Require Dedicated Gas Line?

A dedicated gas line means a direct gas line from the gas meter. 

You will require it for any tankless water heater over 4 GPM capacity.

And for those tank-type water heater that has a 40,000+ BTU/hr power capacity.

12. Can I use gas water heaters for AQUECOIL Heating System?

Surely you can. But surely it will cost massive utility bills at the end of the month!


Top 10 Best Gas Water Heater​ (Tankless & Tank-Type)


1. Natural Gas Tankless Water Heater for Indoor Installation – Rinnai RU199iNer

Rinnai RU199iN
  • Flow Rate – 11 GMP
  • Warranty – 15-year Heat Exchanger / 5 Year Parts / 1 Year Labour
  • Fuel Type – Natural Gas
  • Energy Factor – 0.96
  • Estimated Annual Energy Cost – $201
  • WIFI Enabled?:Yes
  • Ignition Type: Electric Spark Ignition

The matter seems almost unbelievable, but 100% TRUTH, Rinnai RU199iN, offers you an extreme 11 GPM tankless water heating experience with the world’s CHEAPEST operational cost. 

With their own invented condensing technology & intense performer heat exchanger, Rinnai has achieved a 96% energy efficiency rate for this particular model, which is unimaginable for a gas-driven water heater.

That’s the main reason for picking this unit at the top of my choice for Indoor Installation.

Suppose your tap water temperature doesn’t remain too cold. In that case, RU199iN can handle 4-5 appliances simultaneously, which means more than sufficient water for 3 standard shower heads & kitchen or laundry stuff at a time. 

Rinnai Ru199iN produces 15,000 BTU/hr (min) to 199,000 BTU/hr (max) heating power according to demand for supplying a maximum of 660-gallon hot water each hour. The company, by default, set the output temperature at 120F for safety, which is raiseable up to 140F.

Due to Ultra-Low NOx production, it’s an environment-friendly unite. You would require a 2 inch PVC exhaust for indoor installation, and you can place it outdoors without an exhaust.  

Extraordinary Things Of Rinnai RU199iN

WIFI Enabled Smart Unit

 Rinnai RU199iN could be connected to your home wifi, and you can control everything of the unit via the Rinnai 2.0 app, including temperature, timer, holiday mode. The app has a fantastic UI & shows everything you need, including the outlet temperature.

Extended Warranty

No other brands offer 15 years long warranty; even Rinnai doesn’t offer it for all other models. The Parts contain a 5-years warranty & 1-year labor.

Note: We’ve talked with users; they have been using this same unit for 20+ years trouble freely!!! Undoubtedly long-lasting, correct?

Condensing Technology

Rinnai squeezes the total heat with the condensing technology, which consumes all the unused heat from the exhaust temperature to the water. Thus it achieves a 96% energy efficiency rate! 

You will find a little water drip through a small nozzle created by vapor, which is called condensate. It should be safely disposed of.

Final Thought

Rinnai RU199iN is an expensive gas water heater for sure. But at the end of the day, it will save you thousands of dollars each year. So it does worth every penny


2. Propane Tankless Water Heater for Indoor Installation – Rinnai RUCS75iP

Rinnai RUCS75iP
  • Flow Rate – 7.5 GMP
  • Warranty – 12-year Heat Exchanger / 5 Year Parts / 1 Year Labour
  • Fuel Type – Liquid Propane
  • Energy Factor – 0.93
  • Estimated Annual Energy Cost – $497
  • WIFI Enabled?: NO
  • Ignition Type: Electric Spark Ignition

Using liquid propane to produce hot water for the entire house is pretty expensive, but sometimes sadly, we don’t have any other solution! 

Note: The consoling fact is, using electricity is more expensive than LPG dear!!!

Anyhow. Intentionally I’ve preferred a relatively small 7.5 GPM Rinnai indoor propane tankless water heater to recommend you guys instead of a large 11 GPM variant to cut your annual cost slightly. 

Additionally, Rinnai has many more indoor LPG models, but RUCS75iP holds the “Super High Efficiency” tag officially by the manufacturer, and it’s true.    

The unit produces 10,300 BTU/hr (min) to 160,000 BTU/hr heat to raise water temperature up to 75F-140F with a maximum 7.5 GPM flow rate.  

This amount is sufficient to handle two showers or a bathtub & kitchen sink, dishwasher, laundry stuffs at a time, but certainly, the performance will drop in chilled seasons.

The default preset temperature remains at 120F. This model doesn’t have any built-in button, so; you will require to buy a control panel to operate it physically.

Lastly, it’s a condensing water heater and requires ventilation which could be done by a 40 PVC line. 

Due to being propane-driven, it assuredly works at a high altitude.

Things I Love of This

Noiseless Operation

Gas water heaters are noisy by generic, especially the natural gas variants that do act like a jet engine. 

But this propane-powered unit is almost quiet like an electric water heater. As it will remain installed indoors, being quiet is too essential.

Fast Heating

The temperature rising speed of LPG is more than natural gas due to the molecular bond of carbon. So comparing with a similar 7.5 GPM natural gas unit, this LPG variant works faster. 

For example, if the natural gas variant can increase the temperature by 80 degrees with a top flow rate, the LPG variant will raise 80+

Results, in the colder season, you won’t feel that more performance drops.

Extended Warranty & Energy Efficiency

Rinnai RUCS75iP comes with a 12 Year Heat Exchanger, 5-year parts & 1-year labor warranty, and frankly, their after-sale service is excellent!

Due to being driven by LPG fuel, it’s expensive to run, but it has a 93% energy efficiency rate that means this unit requires almost 30% less fuel cost at the end of the day. So, its value for money!

As you require a propane tank to operate this item, you may go through my guide on propane tank size for tankless water heater here.


3. Natural Gas Tankless Water Heater for Outdoor Installation – Camplux Pro NGS

  • Flow Rate – 6.8 GMP
  • Warranty – 1 Year Warranty
  • Fuel Type – Natural Gas
  • Energy Factor – 0.82
  • Estimated Annual Energy Cost – $170
  • Ignition Type: Electric Spark Ignition

To clarify any misconceptions, the outdoor gas tankless water heater isn’t a portable device to carry on campings and use wherever you want. These are tankless water heaters to supply household hot waters only & remaining installed outdoors; it just saves some space and enhances the safety a bit, that’s all…!!!

This unit will be perfect for a 3-bed with 2-bath standard home or 4-5 family members.

I’ve picked Camplux Pro 6.8 GPM as my first outdoor natural gas tankless water heater recommendation because of 3 unbeatable reasons.

  • Camplux Pro offers the BEST price comparing all others from similar segments.
  • It comes with all components inside the packaging, including the remotely installable control panel with 3.3 feet wires. (Nobody offers this.)
  • A perfect combination of performance, safety, cost efficiency & warranty!

Camplux Pro produces max 180,000 BTU/hr heating power to supply unlimited hot water with a 6.8 GMP flow rate. You are allowed to set water temperature from 99ºF(37ºC) to 140ºF(60ºC), and a minimum of 0.79 GPM water flow will activate the unit while it requires natural gas pressure of 1.5-2.6kPa/0.22-0.38 psi.

Impressively, you will get the exact output water temperature even with the highest flow rate. Cause, a same segment water heater from Rinnai & other brands produce 180K BTU/hr for a higher 7.5GPM model. 

Comparing with that, this Camplux pro creates the same amount of energy to supply a lower 6.8 GPM amount of water. Results, you will get a performance like a supercar!

What I like about Camplux Pro

Anti Freezing Technology

Outdoor heaters remain at risk of freezing damage in very chilled temperatures. But the camplux pro has an anti-freezing technology that automatically raises the heater’s internal temperature when the water temperature gets dropped upon 40℉(5℃). So, let’s enjoy an enhanced life span and headache-free life!

Low Nox & Safety Features

Camplux pro has CSA certified flame failure, anti-freezing,  over heating protection,dry combustion protection, low& high water pressure protection & low NOx emission safety checklist. Additionally, it’s an outdoor unite. So nothing can beat its ultimate safety!

Energy Efficient

Gas water heaters have a curse of low energy efficiency, especially the outdoor variants. But Camplux Pro has an energy factor of 0.82 which explains its ability to transform 82% of gas kinetic energy into heating power. And, as it’s a natural gas-driven unit, the running cost is low!


4. Propane Tankless Water Heater for Outdoor Installation – Rinnai RL75eP

Rinnai Outdoor Tankless Hot Water Heater
  • Flow Rate – 7.5 GMP
  • Warranty – 12-year Heat Exchanger / 5 Year Parts / 1 Year Labour
  • Fuel Type – Liquid Propane
  • Energy Factor – 0.82
  • Estimated Annual Energy Cost – $552
  • Wifi Enabled?: YES!!!
  • Ignition Type: Electric Spark Ignition

Suppose you want to save some space installing an outdoor tankless water heater and, LPG is your only available option for fuel. Then Rinnai RUS75eP is undoubtedly an unbeatable choice to fulfill all your household requirements.

With the 7.5 GPM flow capacity and 10,300 BTU/hr(min) to 180,000 BTU/hr (max) massive heating power, this unit can support up to 3 bathhouses or the demands of 4-5 family members easily. This number may slightly get reduced if your environment temperature remains on the minus scale.

As it’s a condensing tankless water heater, the power saving level is sufficient (around 82%). Though, due to the high price point of propane, the annual operation cost is pretty expensive.

Due to being an outdoor unit, you needn’t worry about any NOx emissions or any ventilation. Additionally, it’s SCAQMD approved ultra-low NOx emitting certified.

You would require a remote control panel to operate all the functionality, but you can control it through a WIFI connection using the Rinnai 2.0 app.

What do I like About It?

Easiest Installation

Gas water heaters are slightly complex to install, but among them, Rinnai RUS75eP is relatively easy. The isolation valves come with the packaging, and you won’t require any ventilation or complicated wiring. So it could be DIY installed.

Low Maintenance

We have interviewed several users of RL75eP, who are using this unit for over 25 years trouble freely. It doesn’t require too much maintenance, but only the annual flushing is enough.

Water Modulation

Though it’s a standard technology for all gas tankless water heaters, Rinnai RL75eP does this task exceptionally well. 

Reducing or increasing tap water flow suddenly doesn’t impact output water temperature at all for this controlling sensitivity, which is impressive!

Note: The unit is decent but has a high annual operational cost. Although, among all other outdoor propane variants, this one is one the most efficient. Please keep this fact under consideration. 


5. The High Efficient Gas Water Heater – FOGATTI 4.2 GPM

FOGATTI Tankless Water Heater
  • Warranty – 1 Year Limited
  • Fuel Type – Natural Gas
  • Energy Factor – > 0.81
  • Estimated Annual Energy Cost – Bellow$149
  • Ignition Type: Electronic Ignition

What is Efficiency in terms of Gas water heater? Most people have a misconception, thinking that it represents the lowest annual operational cost. 

Instead, the most efficient gas water heater represents “how effectively the device can burn the gas to produce heat.” According to this concept, our first reviewed product, the Rinnai RU199iN, is the most efficient gas water heater. 

But, keeping our reader’s demand in mind, we are reviewing FOGATTI 4.2GPM tankless water heater considering its

  1. Lowest annual operational cost – bellow $150/year
  2. The high energy efficiency score of 0.81

Please keep in mind; it’s a 4.2 GPM small unit and can only support a small family or a single bathroom with kitchen or laundry tasks.

Why do I like it?

Most Advanced Features

FOGATTI has fully integrated touch control, including POWER, +/-, and ECO mode to maintain any of your comfortable temperatures. The temperature could be set from 95℉ to 149℉ range, and the output water temperature will almost be accurate with the highest difference of ± 1 degree F.

All safety features are integrated with this variant which includes

  • Overheat Protection
  • Flame Failure Protection
  • Anti Frozen Protection
  • Dry Combustion Protection
  • Low water flow Protection
  • High water Pressure Protection

Powerful Output

Using an o2 free Copper combustion, the unit can raise water temperature by 67℉ while the water flow is 4.2 GPM. 

Again if you increase the water flow to 6.2GPM, the device can raise water temperature by 45℉, which will be more than sufficient for a shower!

So, it’s a fantastic machine for a small family to supply the whole house with hot water.

Easy Installation

When we intend to save money, we should obviously focus on cutting down the installation cost. 

You can install FOGATTI by yourself as it’s a compact variant. You would require a 3/4″ NPT water connection, standard gas line, and a φ3″ vent pipe; that’s it!!!


6. The Cheapest Gas Water Heater – EZ 101 Portable Tankless Water Heater

EZ 101 Tankless Water Heater
  • Warranty – 1 Year
  • Fuel Type – LPG
  • Flow Rate – 2GPM
  • Ignition Type– D Cell Battery Powered Spark Ignition
  • Warranty– 1 Year Limited
  • Weight- 14 Ibs Only
  • Dimension– 17.5×11.8×4.7 inch  

EZ 101 has broken all results with its meager price tag among the gas tankless water heater world. However, it’s a portable variant, also applicable for household purposes connecting a 3″ or 4″ vent pipe.

EZ 101 has compromised the LED display to decrease the price range, but all other essential features are integrated to ensure the best user experience.

  1. You can control the flame. 
  2. Also, you can control the burner quantity according to environmental temperature.
  3. And obviously, the water flow amount is controllable too.

The unit comes with a 3 feet lengthy hand shower kit!! So, nobody will resist you get hot water on the go or while remaining at home.

Temperature Raising Ability

The portable heater can raise water temperature by 65F while the flow is on 1.2-1.5 GPM, and with a high amount of water flow, it will rise by around 50F.

Due to having the burner control (Summer/Winter), the operational cost will remain highly efficient.

Automatic Ignition Control

The device will turn on automatically once you start the water flow. You will require a D cell battery for spark-ignition purposes. If you use this daily, the battery lasts for more than six months.

Build Quality

Though it’s cheap, the build quality is of the ultimate level. You will never be able to complain about it.

Before Reviewing the Tank-Type Gas Water Heater

Discussing with design or functionality of a tank-type gas water heater will be nothing but wasting your precious time, as they are too simple and straightforward, which I never wanna do. 

So I will describe more about user experiences, water heating cost & timing, inconveniences if they exist, longevity experiences, and stuffs like that instead of features and functionality.


7. Best 50 Gallon Gas Water Heater – A.O Smith GPVL-50 ProMax

A.O. Smith GPVL-50 ProMax
  • Warranty – 6 year Tank & Parts
  • Fuel Type – Natural Gas
  • Energy Factor – 0.62
  • Estimated Annual Energy Cost – $233 to $259
  • Ignition Type: Piezo Pilot Light Electric Igniter

A.O Smith GPVL ProMax 50 Gallon gas water heater is designed to be used as the primary hot water source of a 4-members family. Among all tank-type gas water heater, this variant is the most demanded & familiar one to all standard families.

You can install the unit both indoor & outdoor, as it’s a direct vent model and contains a 2-pipe combustion system to draw clean air from the outer environment. Additionally, the system can vent up to 40 feet using a 3″ venting pipe. So your home will remain entirely free from all shorts of emission.

A.O smith can raise water temperature up to 180F by its 40,000 BTU/hr massive capability. The hot water remains isolated from the colder region due to an inlet pressure optimization done by the kit called “Dynaclean ii dip tube.” As a result, you won’t face temperature fall too gradually.

What do I love about it?

Highly Insulated Tank

The internal tank is insulated with 2-inch thick environmentally friendly polyurethane foam to hold the water temperature on point for up to 18 hours. Thus you get instantly ready hot water flow in the highly efficient way possible.

Safety Features

  1. Integrated fire safety feature protects the unit from any accidental fire, including flammable vapors.
  2. Electronic gas valves ensure longevity by their less moving components comparing mechanical valves.
  3. The ceramic coating protects the tank from easy leakage, and the anode rod resits any corrosion for harsh water chemistry.
  4. Although the unit starts with a piezo light ignition, it’s electronically operated. So there’s no chance of being flameout.

Standard Family Capacity

You can enjoy a 34-minute long shower with a 4.3 GPM showerhead. 

Or at a time, you can operate two showerheads, an 85-gallon bathtub, and all household stuff of a standard 4-member size family.


8. Best 40 Gallon Gas Water Heater (Cheapest Priced) – A.O Smith GCR-40 ProMax ​

A.O. Smith GCR-40 ProMax
  • Warranty – 6 year Tank & Parts
  • Fuel Type – Natural Gas
  • Energy Factor – 0.62
  • Estimated Annual Energy Cost – $263 to $277
  • Ignition Type: Piezo Pilot Light Electric Igniter

If you don’t have a very high volume of hot water demand, you may prefer this tank-type unit with the cheapest price tag. It’s almost 2.5x less priced comparing the immediate larger 50 gal variant but produces the same 40,000BTU/hr heating power to provide a strong heating experience.

A.O smith GCR 40 ProMax contains every safety feature to ensure your household security. 

  • Anti flame safety. 
  • Electronic Piezo Pilot Light.
  • Electronic gas valve with fewer moving parts 
  • Microprocessor to run self error diagnosis algorithm and control exact water temperature.

This unit requires ventilation to keep your house free from any toxic gas emissions.

The tank is blue glass-ceramic coated to remain free from harsh water corrosion. An environmentally friendly 2-inch polyurethane foam insulation keeps the water temperature on point for as long as 12 hours. 

Additionally, there’s an anode rod to consume all minerals of hot water to keep the tank cleaner and damage-free in the long run. You will require to change it every 2-3 years, depending on your water chemistry.

What do I like about it?

Small but powerful!

It’s a 40-gallon unit but produces the same 40,000 BTU/hr heating power similar to the larger 50-gallon variant. Results you an ultimate cut down of waiting time to get hot water faster. 

Keep Hot Water Isolated

In a Tank-Type water heater, the cold water enters the same hot water tank from the cold inlet. But you must know, hot water density is less than colder one and lighter in weight. 

So a valve called Dyclean ii. reduces the inlet water pressure to keep the hot water at the upper level and remain isolated from the colder region. So, it does lower the amount of gradual temperature fall.

Internal Micro Processor

An internal electronic microprocessor controls the water temperature, gas inlet valve, piezo ignitor light and does self-diagnosis using its algorithm to identify if any error occurs. 

So, the machine takes care of its own, keeping you out of the headache of a shorter lifespan. Additionally, A.O smith has six years of parts & a limited tank warranty!


 9. Best 75 Gallon Gas Water Heater – A.O Smith G6-PVT7576NV

A.O. Smith GPVX-75L ProMax

Rarely 75-gallon tank-type gas water heaters are being used for residential purposes, although I don’t know why! 

Cause, despite the slightly high price tag, the annual operation energy cos is incredibly lower than the 50 or 40 gal unit. So, there should be no reason for not preferring this.

Using a 4 inch PVC, ABS, or CPVC vent pipe, you can pass the exhaust both through the wall or by drilling the roof. An integrated microprocessor does self-diagnosis of the mechanical status, and the electronic gas valve ensures the highest energy efficiency.

This is one of the rarest A.O smiths models that contain self-cleaning technology to keep the tank fresh. Also, the tank is porcelain layered and includes an anode rod to consume corrosive minerals.

What do I love?

Powerful But Efficient

The unit will roar with 75,000BTU/hr energy production capacity to raise the tank water up to 180F. 

You are allowed to take a 63 minutes long shower using a 7.9GPM showerhead!

Or simultaneously, you can use a 7.9GPM showerhead, a 4.4GPM shower, a 134-gallon bathtub, and all sorts of household activity, spending a very minimal annual energy cost.

Electronic Controls

All the safety features are electronically controlled, and errors are diagnosed by a microprocessor and shown to an LED display. Undoubtedly it’s an advanced water heating solution.

Long Term Usability

If you do some essential maintenance like flushing the tank and replacing the anode rod timely, this machine will serve your grandchildren for sure. (Assuming that you are a newly married young man/woman!)


10. Best Commercial Gas Water Heater -American Standard AS-80

American Standard Water Heaters
  • Warranty – 3 year Tank & 1-year Parts
  • Fuel Type – Natural Gas
  • Energy Factor – 0.80
  • Estimated Annual Energy Cost – $335+ according to uses.
  • Ignition Type: Electronic Direct Spark Ignition System

Using a tank-type natural gas water heater is the only way to efficiently supply a sufficient amount of hot water to commercial zones. Cause

  • The tankless water heater has a water flow limit (GPM), so multiple hotel clints or restaurant consumers won’t get enough hot water simultaneously. So tank-type would be the best solution.
  • Natural gas is a cheaper fuel than propane, kerosene, or electricity in this case.
  • The natural gas tank-type water heater is very long-lasting, so it’s the ultimate value for money.
  • A high BTU gas water heater heats faster than any other type of water heaters.

So, the American Standard AS-80 is an unbeatable choice for restaurants, hotels, motels, inns, or even in construction sides, schools, collage, hospitals, shopping complexes, and many more.

According to your necessity, you may prefer 75, 80, or up to 100-gallon tank size and 125,000 up to 512,000 BTU’s heating capacity. 

Now I will briefly describe on 80 gallons 199K BTU variant and its compactable sectors of uses.

How Many Users Can It Handle?

The 80 gals 199K BTU model can handle 30 single bath or 21 double bath units entirely on hotel/hospitals/inn/motel installation.

It can handle up to 100 consumers at a time with staff and kitchen demands for restaurant installation. 

For a shopping complex, it’s more than sufficient for a 15,000-20,000 sqft shopping zone.

Lastly, the model can handle 60 workers’ daily water demands with additional necessities for the construction side.

Essential Features of this Model

  1. Corrosion protected DURA-GLASS lined steel tank 
  2. Heat exchanger fires on 1600F to protects the unit from chemical corrosion.
  3. NON-CFC foam insulation holds water temperature for very long hours.
  4. Equipped with four anode rods to enhance tank life.
  5.  Automatic Motorized Flue Damper for standby periods cost reduction.
  6. 300-PSI pressure tested and activation 150-PSI working Pressure.
  7. 140F to 180F fully adjustable temperature.
  8. 80% Plus energy efficiency.
  9. 5 Split heat exchanger for fast heating capability. 

Note: To ensure the best performance & efficiency, measure your required gallon size and choose a higher BTU from 199K to above.


Essential Facts to Know About Gas Water Heater

“Priority Button” Explanation of a Gas Tankless Water? 

You will find a button named “Priority” at almost all high-capacity tankless water heaters. Here is an explanation of how it works.

You can install multiple electronic control panels for your household tankless gas water heater. For example, One controller in the kitchen, one in the bathroom, one in the laundry, and the last one near the dining sink.

If you set the kitchen controller temperature to 140F and press “Priority,” the adjacent controller’s green light will get turned ON. It does mean to the user that this particular controller is currently remaining active.

Again if you go to the bathroom and set the temperature to 90F and press “priority,” then the bathroom’s controller will start working, and its green light will get turned ON.

So, by pressing the priority key, you can specify which controller you want to remain active, and you can identify the status by looking at the green light.

What is Condensing gas Water Heater?

Condensing technology is a key mechanism to enhance power efficiency.

All the gas water heaters have a vent or exhaust pipe for ventilation (Similar to your car), and the vent air remains too hot. 

But in condensing water heater, a condenser tube absorbs the exhaust/vent temperature to raise the water temperature, and thus, it increases thermal efficiency by 96%. In these types of gas water heater, the vent air remains cool.

Inside these condensing water heaters, you will find a plastic pot to collect condensate water drips. This condensate water should be disposed of safely as it’s slightly acidic due to the mixture of burned gas.

So these are the Condensing water heater, and all others are called non-condensing, that’s it.

Some Basic Maintenance of Gas Tankless Water Heater 

  • Once a year, flush it with vinegar. (Do it by yourself will cost < $20)
  • Clean condensate water
  • Keep the vent clear
  • Try to identify if any cracking noise is coming from the combustion fan.
  • Winterize if require.

Tank Type Gas Water Heater Basic Maintenance

  • Check anode rod every year and change it if required.
  • Keep the vent pipe clean.
  • If too much mineral gets stuck to the tank, clean with professionals.

Can I install an Indoor tankless Water Heater to Outdoor & Vice Versa?

The indoor water heater can be installed outdoor, under a shed, or where it may remain safe from a heavy splash of rainwater.

But an outdoor water heater isn’t installable indoors, unfortunately.

Is there any chance of set fire? How Safe is Gas Water Heater?

If you do regular maintenance and a professional plumber installs the unit, then these machines are entirely safe. But to avoid any accidental case, especially in terms of indoor installations,

  • Check and double-check with soapy water if there’s any leakage.
  • Keep a gas identifier sensor to detect any toxic gas emissions.

Thus you will remain safe.

How Energy Efficient are They?

Condensing indoor tankless gas water heaters are the most efficient machines with a 96% energy factor. 

Non condensing indoors or condensing outdoors has a lower energy efficiency of around 81% to 86%.

Tank-type gas water heaters are less efficient as their energy factor is around 61% to 70%

Note: Energy factor explains how much percentage of gas burned kinetic energy is being converted into heat energy. SO, the higher, the better.

Can Gas Water Heater Run Without Electricity? 

No. Not at all.

Although it works by burning gas, electricity drives the entire controlling processor, the ignitors, sometimes the power vents, and the combustion fan’s motor.

So there is no way to run a gas water heater out of electricity.

Except for the portable gas water heaters that require D cell batteries to ignite the unite.

The assumption for Defect Repairing Cost

Between the warranty period, you will need only a labor fee. Out of warranty period

  1. Spark ignitor failure will cost around $50
  2. Piazo Ignitor Failure will cost approximately $30
  3. Tank leakage repairing will cost about $100
  4. Controlling processor damage will cost around $150-$200
  5. Valve damage will cost not more than $30~$50

These are all basic maintenance costs.

Should I think of an Indirect Water Boiler?

An indirect water boiler is a combination of 1 tankless water heater & 1 tank-type water heater installation. If you install them on series (first the tankless, then the tank-type on sequence)

  • You will get unlimited boiling point hot water.
  • A frigid environment temperature will not affect water heating performance.
  • All barriers of tank-type & tankless water heater will be removed.

Now, should you think of it? If you have that financial capability and, most importantly, if you badly need this amount of hot water, then you may think of it!