Choosing The Best Mobile Home Water Heater For You

As I researched for this mobile home water heater article I found several products being sold that were not HUD approved. Which means that your homeowners insurance won’t pay for any damages caused by the water heater.

That would also void the water heater’s warranty, because it wasn’t used in an approved manner.

I have made sure that every mobile home water heater in this article is officially HUD approved for use in mobile and manufactured homes. I even provide the documents that prove it.

Mobile Home Water Heater

Best Mobile Home Water Heater Choices

While all residential water heaters operate in essentially the same manner, there are a few distinctions to note that are vitally important when choosing a replacement mobile home water heater.

These differences are the key to ensuring safe, worry-free operations at all times – while meeting your specific hot water needs, at a price that’s affordable. And by the way, this applies to any manufactured, modular, or mobile home.

Looks Like A Typical Water Heater

Whatever brand or model of water heater you select for your mobile home will likely look and functions much the same as any conventional water heater used in homes that are built on site.

Two Key Qualifiers

But the critical difference is that any device used to supply hot water to a mobile home must be rated for mobile home use. Typically, this means that it needs to include sufficient space around the device as well as proper ventilation. If you opt for a tankless mobile home water heater – it needs to be securely fastened to a wall of the home to prevent any movement.

Secondly, every water heater used in a mobile home must be HUD approved. This means that every manufactured or mobile home water heater needs to meet specific standards set out by the U.S. department of Housing and Urban Development.

The best way to ensure you’re getting a water heater that is both rated for mobile homes and is HUD approved is to refer to the owner’s manual provided by the manufacturer. You can find the instruction manual to the two top brands we recommend by clicking this link – or this one.

Essentially you can choose between a tank-type water heater and a tankless system. Out first recommendations are tank-based water heaters – powered either by liquid propane or natural gas.

How Propane and Natural Gas Water Heaters Work

These types of water heaters work by burning fuel. They also need to have a source of air and proper ventilation. Cold water enters the water heater through the built-in dip tube and flows to the bottom of the tank. The system pushes the hot water out of the top through the outlet connection. This design supplies maximum efficiency so that you get the most water out of – whatever size of tank you choose.

When cold water enters the tank, a temperature sensor automatically opens the gas valve. The pilot light is ignited and gas flows to the burner. Air needed for the water heater to function is supplied by the room the device is located in and the exhaust is always vented to the outside. When the correct water temperature is reached, the gas valve shuts off automatically.

All of these tanks have temperature and pressure release valves built-in (T&P valves). This is provided as a safety mechanism. It’s designed to provide relief should the internal temperature or pressure of the tank exceed its preset limit.

The water heater you choose should be large enough to provide ample hot water for you and your family even when the temperatures are at the coldest times of the year and when the demand for water in your house is highest.

Top Two Brands Offer A Variety of Mobile Home Complaint Water Heaters

When it comes to choosing a reliable, quality-built water heater for your mobile home, our top choices come down to two specific brands – A.O. Smith and Rinnai. Both companies are well established manufacturers offering a broad range of suitable water heaters. We’ve narrowed it down to the best ones of the bunch so you can choose a mobile home water heater that meets your needs, space allowance – and budget.

As it turns out, A.O. Smith has a few more models of suitable water heaters to offer mobile home owners. And there’s no doubt about it – A.O. Smith makes a top-quality water heater in the traditional tank-type style. The biggest difference A.O. Smith offers is in how they’ve taken a traditional design and modernized it, making it a superior product to the run of the mill, standard water heaters on the market.

In our view, our recommended A.O. Smith water heaters represent the evolution of the tank style water heater – made specifically for mobile homes.
All of our selected models from A.O. Smith come complete with the following:

1. Superior resistance to corrosion thanks to the blue diamond glass coating inside the tank. Most companies use standard glass. But A.O. Smith insists on their blue diamond glass coating to help the tank last longer.

2. Some electric models have Dual 4,500 Watt heating elements to provide a reliable and steady flow of hot water and fast recovery times. For greater durability, the lower element is made of Incoloy stainless steel which tends to lasts longer than the standard copper element.

3. Anode rod with a stainless steel core outlasts any standard anode rod. That’s another way A.O. Smith provides better tank protection than most.

4. Built-in diffuser dip tube helps reduce the buildup of lime and sediment to maximize hot water output. It’s made of a cross-linked polymer PEX material that’s built to last.

5. Some models have a solid brass, ball-type drain valve which is durable and tamper-resistant. Brass holds up much better than plastic, which is often used on other drain valves.

6. Easy to operate drain valve. With a simple one quarter turn of a screwdriver, you either fully open or safely close the valve.

7. Another benefit of the A.O. Smith mobile home water heater line is that they are an eco-friendly tank type water heater thanks to their foam insulation, heat traps and other built-in features. It’s all designed to maximize efficiency and save you money on your water heating costs.

8. All of our recommended A.O. Smith water heaters are certified HUD approved for manufactured and mobile homes.

Recommended Water Heaters For Mobile Homes

What follows is our list of the best mobile home water heaters by the A.O. Smith brand. All are from their Promax line of water heaters which features quality parts, modern technology and a higher grade of tank compared to most competitors on the market today.

Typically, the warranty on these mobile home water heaters is good for a period of six years, though some tanks come with a ten year warranty.

AO Smith ENT–50 ProMax® 50-Gallon Electric Water Heater

The ENT–50 has a 50 gallon tank capacity. It is 22 inches in diameter and measures 60.5 inches in height.

It comes complete with all the A.O. Smith standard benefits and features including the factory installed temperature and pressure release valve, dip tube, enhanced heating elements – plus the stainless steel core anode rod to provide a higher degree of protection to the tank.

Get This Very Popular Family Water Heater – Click Here

By deploying dual 4500 Watt elements, the ENT–50 can supply 71 gallons of water in the first hour at a surprisingly efficient energy factor of 0.95. It’s made with quality parts featuring stainless steel, brass and the blue diamond glass coating on the tank. This one supplies consistently hot water throughout your mobile home while resisting the natural corrosive effect of water – giving you better mileage and value.

Key Specifications

Gallon Capacity: 50
Wattage: 4500
Voltage: 240
Energy Rating 0.95

Size: 22 inches by 22 inches by 60.5 inches high
Total Weight: 134 pounds
Water Connection Size 0.75 inches
Water Connection Location: on top of the unit

Recovery Rate At Rise of 90 Degrees F: 21 gallons per hour
HUD compliant

AO Smith EJCS-20 Promax Water Heater

The EJCS-20 Promax water heater from A.O. Smith features what is known as a “lowboy” design. It’s short and stocky but every bit as effective at supplying plenty of hot water as required. In this case, the overall dimensions are 18 inches in diameter by just 24.75 inches in height.

This lowboy design features side connections which some people find a little easier to work with (during installation) due to the lower height.

The AO Smith EJCS-20 is easy to install. Order This Now – Click Here

Key Specifications

Gallon Capacity: 19

Wattage: 2500

Voltage: 120

Energy Rating: 0.98

First Hour Gallon Production: N/A

Size: 18 inches by 184 inches by 24.75 inches

Weight: 65 pounds
Recovery Rate At Rise of 90 Degrees F: 11 gallons per hour

HUD compliant

Read my review of the AO Smith 38 gallon lowboy water heater.

AO Smith Signature 100 Series Water Heaters

Nominal Capacity40 Gal.40 Gal.30 Gal.30 Gal.
BTU Input32,000 BTUs35,000 BTUs30000 BTUs35000 BTUs
Natural gas/Propane Yes Yes Yes Yes
Tank Guard™Yes Yes Yes Yes
Flame GuardYes Yes Yes Yes
Uniform Energy Factor (UEF)0.590.560.610.61
Warranty6 years6 years6 years6 years
Family Size423
Height58 3/4″58 1/2″58″
Height w/Draft Hood61 3/4″62″61″61.5
Diameter20″19 3/4″18″ 18″
Width20″19 3/4″18″
Depth20″19 3/4″18″
VentTypeDirect VentStandard VentDirect VentStandard Vent
Vent Diameter3″3 or 4″3″3″
Insulation Thickness (Inches)2222
High Altitude ModelYesYesYesYes

Why Consider A Tankless Model As Your Mobile Home Water Heater Of Choice?

We recommend several models of tankless water heaters. All of them are manufactured by Rinnai. It’s important to note that not all tankless water heaters are made for mobile homes. By following our recommendations, you can rest assured that you’re getting a tankless water heater that is mobile home and HUD approved.

There’s no question, Rinnai builds quality tankless water heaters. And one of the nice features they offer is that every component can be replaced. This means you don’t have to replace the entire tankless water heating system should a single part or two malfunction or wear out.

Rinnai’s tankless technology uses copper heat exchangers to provide maximum efficiency. And in effect, this design style uses about 40% less energy than traditional tank water heaters. And with an electronic ignition, there’s no standing pilot light that constantly uses energy. Although it’s a relatively small amount, any savings here goes straight into your bank account.

Save Money Three Ways

Buying a tankless water heater – and more specifically a Rinnai model – can actually save you money in different ways. You save money by increasing your energy efficiency which lowers your utility costs. The second way you save money is through any available energy efficiency rebates that are offered from various levels of governments in different areas. And the third way you save money with a Rinnai tankless water heater for your mobile home is through the additional years of service you can typically get from a quality tankless system versus a standard tank type water heater.

Saves Your Space Too

Tankless water heaters like the ones we recommend from Rinnai below are quite compact in size. In fact, they only occupy the same space as a small suitcase would. They’re all wall-mounted units. Some can be installed on interior walls while other models are designed to be installed only on exterior walls. Since they’re much smaller in size, it frees up valuable space previously occupied by a large hot water tank.

Since these tankless systems are so compact, they are perfect for installing in places like attics and crawlspaces in regular homes. They’re also perfect for manufactured, modular and mobile homes and can be installed in alcoves and small closets easily.

These tankless systems also tend to last twice as long as a traditional tank-style water heater. A standard tank type water heater can last anywhere from 8 to 15 years. And a tankless water heater can last anywhere from 20 to 25 years.

Rinnai tankless water heaters also produce lower CO2 emissions, contributing to a healthier environment for all.

Pros and Cons

The only real downside of going to a tankless water heater for your mobile home is that the upfront costs are slightly higher and you may have to wait a few seconds for the water to flow at the perfect temperature for you. But when you look at overall savings gained plus the extended years of uninterrupted service – a tankless can make a lot of sense.

How A Tankless Mobile Home Water Heater Works

Cold water enters the system via the inlet pipe. But it only does so as hot water is required. Activation is triggered by the demand for hot water. So, as soon as someone turns on the tap – that’s when the system kicks in. The gas ignites the heat exchangers which immediately begin to heat the water. It’s the quick heating of these tankless systems that make them so effective.

As the water is heated – it flows out the hot water outlet travelling through the pipes of your mobile home to wherever that water has been requested. These tankless systems automatically adjust the heat output to maintain the temperature set-point. That way you get a steady and consistent flow – at just the right temperature.

RL models deliver 82% efficiency. They’re also Wi-Fi enabled and ready for easy monitoring. And these highly-efficient water heaters are available both natural gas and propane versions, as you’ll see below.

Flow Rates Instead of Total Gallon Capacities

Tankless water heaters are measured by flow rate (gallons per minute or GPM) as opposed to total gallons of water. Temperature rise refers to how far the temperature of incoming water needs to rise to get it to the right temperature for you.

The best way to estimate what size of water heater is best for you is to imagine all your hot water appliances and taps being used at the same time. Then project how much water flow you’re going to need at a maximum level.

Typical Flow Rates (in GPM)
Kitchen Faucet: 1.5 GPM
Dishwasher: 1.5
Bathroom Faucet: 0.5 to 1.5
Shower 1.0 to 2.0Washing Machine 2.0

Our Highest Rated Tankless Mobile Home Water Heaters By Rinnai

Here is an enlarged image of part of the Rennai Direct Vent Tankless Water Heater Installation and Operation Manual that shows that these must be installed according to the the HUD requirements.

Enlarged portion of the Rinnai Direct Vent Tankless Water Heater Installation and Operation Manual showing that these water heaters must be installed according to HUD standards for manufactured homes (mobile homes).
Image courtesty of Rennai

Rinnai RL75IN Tankless Water Heater

The RL75IN by Rinnai. This RL75IN model measures just 9 inches deep by 14 inches wide and 23 inches high – yet it’s a powerhouse with 180,000 BTUs.

This one is a natural gas water heater that’s perfect for mobile home. Since it’s tankless, it takes up less room and is more energy efficient – so you win multiple ways.

This Rinnai tankless water heater quickly heats water without the need to store it. This helps you avoid heating water that’s not going to be used immediately – saving you money on your monthly bill. That’s a big reason for going tankless right there. But there are other advantages too.

RL75IN Luxury Series Natural Gas Tankless Water Heater. Get It Now – Click Here

Rinnai’s RL75IN model is energy Star qualified, so it’s more efficient than traditional water heaters. It also comes equipped with temperature lock function to prevent scalding. Enhanced scale detection helps keep the unit operating efficiently.

This innovative design provides an endless supply of hot water. You can use several taps and complete multiple tasks at the same time – without ever running out of hot water.

Key Specifications

Natural Gas Model
180,000 BTUs
Indoor installation only
120 volts (the same as any household outlet)
Water temperature ranges from 98 to 140°F
Warranty is as follows – 12 years on the heat exchanger, five years on parts, one year on labor
Energy factor: 0.82
Mobile Home Certified
Minimum activation rate: 0.4 gallons per minute
Weight: 50 pounds
Energy Star Certified
HUD approved

Rinnai RL75IP Liquid Propane Tankless Water Heater

Model RL75IP water heater by Rinnai is a liquid propane powered tankless system with 180,000 BTUs. It provides ample hot water on demand – without the need to store hot water and saving you the cost of providing all that standby heat.

With Rinnai you’re getting a smartly engineered water heating system that features premium technology and maximum energy efficiency. Using this water heater will improve your home’s energy rating system and can therefore help increase the value of your mobile home. That’s something to keep in mind – particularly if you ever fancy putting your home up on the market.

Click Here to check the price on this RL75IP Luxury Series Liquid Propane Tankless Water Heater with 180,000 BTUs

This tankless residential water heating system provides a high level of output in a small amount of space. This means that the RL75IP could be installed in a crawlspace, attic, closet, or crawlspace.

Key Specifications

Liquid Propane Model
180,000 BTUs
Indoor installation only

Size: 9 inches deep by 14 inches wide by 23 inches high
120 volts (the same as any household outlet)
Water temperature ranges from 98 to 140°F
Warranty is as follows – 12 years on the heat exchanger, five years on parts, one year on labor
Energy factor: 0.82
Mobile Home Certified
Minimum activation rate: 0.4 gallons per minute
Weight: 50 pounds
Energy Star Certified
HUD approved

Rinnai RL94IP Propane Tankless Water Heater

The RL94IP by Rinnai deploys liquid propane as its fuel source and boasts a whopping 199,000 BTUs of heat. You can count on hot water quickly to any tap – even multiple taps simultaneously.

This tankless mobile home water heater is designed for efficiency with copper heat exchangers that use up to 40% less energy.

Physically, this one is the exact same size as the other previously mentioned Rinnai tankless water heaters. Exact dimensions are as follows: depth is 9 inches, width equals 14 inches and the overall height comes in at 23 inches.

It’s only slightly heavier at 56.20 pounds – but the additional BTU’s means it can deliver water at a higher capacity.

Rinnai RL94IP Luxury Series Liquid Propane Tankless Hot Water Heater 199,000 BTU Get This Now Click Here

Key Specifications

Liquid Propane Model
199,000 BTUs
Indoor Installation Only

Size: 9 inches deep by 14 inches wide by 23 inches high
120 volts (the same as any household outlet)
Water temperature ranges from 98 to 140°F
Warranty is as follows – 12 years on the heat exchanger, five years on parts, one year on labor
Energy factor: 0.82
Mobile Home Certified
Minimum activation rate: 0.4 gallons per minute
Weight: 56.2 pounds
Energy Star Certified
HUD approved

Rinnai RL94IN Natural Gas Hot Water Heater

The RL94IN model from Rinnai is their tankless natural gas version of the RL94IP.

If you want maximum hot water on demand and your home is equipped with natural gas – this is the model for you. This tankless water heating system offers significant heating power with 199,000 BTUs.

The size is identical to the RL94IP too. It is 9 inches deep, 14 inches wide and 23 inches in height. By the way, it’s important to always install your tankless water heater in the upright position.

Check The Price – Click Here

Key Specifications

Natural Gas Model
199,000 BTUs
Indoor Installation Only

Size: 9 inches deep by 14 inches wide by 23 inches high
120 volts (the same as any household outlet)
Water temperature ranges from 98 to 140°F
Warranty is as follows – 12 years on the heat exchanger, five years on parts, one year on labor
Energy factor: 0.82
Mobile Home Certified
Minimum activation rate: 0.4 gallons per minute
Weight: 56.2 pounds
Energy Star Certified
HUD approved

Read more about Rinnai tankless water heaters here.

Our Verdict On The Best Mobile Home Water Heater

You have several options here to choose from (including tank-based and tankless) when selecting a replacement mobile home water heater. And you can choose with complete confidence, knowing that each of our recommendations is both mobile home and HUD approved.

Comfort, convenience and the well-being of you and your family should always come first. It’s important to consider the hot water needs of everyone at home and ensure that the choice you make will provide you with plenty of hot water on a daily basis.

We recommend choosing the largest water heater possible to ensure you always have lots of hot water on tap. But you also need to match your existing system – whether its propane or natural gas. And it’s crucial that you consider the available space in which to house the water heater for your mobile home.

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4 thoughts on “Choosing The Best Mobile Home Water Heater For You”

  1. Hello I am a building inspector in Connecticut and had a customer reference you page after I had failed their inspection. Some of the water heaters you have listed are not correct and can not be installed in a mobile home. You are giving unsafe advice you will want to correct. This is for both gas and propane. Please read the manuals as they say do not install in a mobile home or manufactured housing. The draft hood is the issue and can lead to CO poising. They don’t have enough height for a proper draft. page 6

    • Hi Daniel, thanks for catching my error. I did specifically read each instruction manual before putting the water heater in the article, but apparently I made a mistake. Maybe I looked at the wrong manual for the specific water heater. SO, I will check each water heater in the article and list a link to the manual.


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