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Buying guide · 10 min read · Updated October 2, 2026

6 Best RV Water Heater in 2026: A Practical RV Guide

Compare two Suburban 6-gallon tank heaters and four propane tankless RV water heaters by BTU, cutout size and 12V power needs.

Bowen HigginsBy Bowen HigginsRV Editor at RV Gear Lab6 products comparedSpec-sheet researched

At a glance

Our top picks

At a glance · 6 picks

  1. Suburban SW6DE 6-Gallon RV Water Heater
    Best OverallSuburban SW6DE 6-Gallon RV Water Heater↓ See why we picked it
    Check price
  2. Suburban SW6D 6-Gallon RV Water Heater
    Best Basic TankSuburban SW6D 6-Gallon RV Water Heater↓ See why we picked it
    Check price
  3. FOGATTI InstaShower 7 RV Tankless Water Heater
    Best Value TanklessFOGATTI InstaShower 7 RV Tankless Water Heater↓ See why we picked it
    Check price
  4. FOGATTI InstaShower 8 Plus RV Tankless Water Heater
    Best Premium TanklessFOGATTI InstaShower 8 Plus RV Tankless Water Heater↓ See why we picked it
    Check price
  5. ORBEK RV Tankless Water Heater
    Best High-BTU TanklessORBEK RV Tankless Water Heater↓ See why we picked it
    Check price
  6. MapleGrace RV Water Heater
    Best Budget TanklessMapleGrace RV Water Heater↓ See why we picked it
    Check price

RV water heaters come in two real types: a 6-gallon tank unit like the Suburban that stores hot water, and a propane tankless unit that heats on demand. The choice turns on how much hot water you use in a row, how big your existing cutout is, and whether you can supply the 12V control power a tankless unit needs.

This hub sorts six picks into those camps and explains what each trades away. Headline GPM figures mean little without the inlet and outlet temperatures, and propane tankless units typically still need 12V power, so read both before buying.

RV Gear Lab field notes

The Rig Fit Check

Start with the job
Suburban SW6DE 6-Gallon RV Water Heater leads this shortlist for Like-for-like tank swap. Use that fit as a reference point, then compare the alternatives against your own space and workload.
Specs that separate the picks
The first details to compare are 6 gallon, DSI and electric, 6 gallon, DSI, 2.5 GPM, 48,000 BTU. Confirm the exact model and included components before ordering.
Trade-off to plan for
6 gallons runs out faster than tankless

Before you buy

What Matters Before You Choose an RV Water Heater

Key buying criteria so you get the right fit the first time.

  1. 01

    BTU and flow

    BTU is heating power, while GPM is flow at a specific temperature rise, such as 40 or 60 degrees. A GPM number without the rise is incomplete. Look for both and compare them within the same type.

  2. 02

    Tank versus tankless

    A 6-gallon tank runs out after a limited amount of hot water and then needs time to recover, while a tankless heats continuously. Tankless units need adequate gas supply and flow. Match to your household.

  3. 03

    12V power requirement

    Many propane tankless units still need 12V DC to run the fan and control board. Your battery must support it. Check the listing for voltage and draw.

  4. 04

    Cutout and venting

    Your existing opening decides what fits, and doors and vents vary. A wrong fit means carpentry. Measure the opening and compare it to the 13 by 13 inch size named on some listings.

  5. 05

    Altitude and freeze protection

    Burners need adjustment above certain altitudes, and tanks can freeze in winter. That matters if you camp in the mountains or in winter. Look for an altitude rating, such as 9,800 feet, and freeze notes.

  6. 06

    Certification and venting safety

    Propane appliances produce combustion gases, so a named certification and correct venting matter. A poor install can be dangerous, not just inefficient. Look for CSA or similar marks and follow installation instructions.

Our standards

Why You Can Trust RV Gear Lab

At RV Gear Lab, we compare products based on rig fit and power or hookup compatibility, verified specifications, usability, setup requirements, weight, durability, and real-world trade-offs. We do not rank products purely on marketing claims or commission rates.

We have not personally tested every product listed. Where hands-on testing is not available, recommendations are based on verified manufacturer specifications, product documentation, use-case fit, and comparative research.

How we review RV gear →

Detailed reviews

The 6 best rv water heater, explained

01

Best Overall · 1 of 6

Suburban SW6DE 6-Gallon RV Water Heater

Suburban SW6DE 6-Gallon RV Water Heater
  • 6 gallon, DSI and electric
  • Porcelain-lined steel tank
  • Replaceable anode rod
Check price on Amazon for Suburban SW6DE 6-Gallon RV Water Heater (opens in a new tab)
Best for: Like-for-like tank swap

Our take

Best for owners who want a familiar tank unit with dual fuel.

Why it made the shortlist

The Suburban SW6DE is a 6-gallon RV water heater with direct spark ignition and an electric element, built with a porcelain-lined steel tank. It has a replaceable anode rod and a flue tube design Suburban says improves heat transfer.

Against the Suburban SW6D, it adds the electric element so you can heat on campsite or generator power, for a higher price.

What works

  • Electric element gives a second heat source
  • Replaceable anode rod protects the tank
  • Porcelain-lined steel tank
  • Direct spark ignition

Watch out for

  • 6 gallons runs out faster than tankless
Check price on Amazon for Suburban SW6DE 6-Gallon RV Water Heater (opens in a new tab)
02

Best Basic Tank · 2 of 6

Suburban SW6D 6-Gallon RV Water Heater

Suburban SW6D 6-Gallon RV Water Heater
  • 6 gallon, DSI
  • Porcelain-lined steel tank
  • Replaceable anode rod
Check price on Amazon for Suburban SW6D 6-Gallon RV Water Heater (opens in a new tab)
Best for: Budget tank replacement

Our take

Best for a straightforward gas replacement.

Why it made the shortlist

The Suburban SW6D is a 6-gallon direct spark ignition water heater with a porcelain-lined steel tank and replaceable anode rod.

Versus the tankless units, it holds 6 gallons and heats slower.

What works

  • Direct spark ignition
  • Porcelain-lined steel tank
  • Replaceable anode rod for corrosion

Watch out for

  • Electric heating is optional
  • Limited 6 gallon capacity
Check price on Amazon for Suburban SW6D 6-Gallon RV Water Heater (opens in a new tab)
03

Best Value Tankless · 3 of 6

FOGATTI InstaShower 7 RV Tankless Water Heater

FOGATTI InstaShower 7 RV Tankless Water Heater
  • 2.5 GPM, 48,000 BTU
  • High altitude to 9,800 ft
  • 150 PSI valve, 6.6 ft remote
Check price on Amazon for FOGATTI InstaShower 7 RV Tankless Water Heater (opens in a new tab)
Best for: Tank-to-tankless conversion

Our take

Best for owners converting from a tank with three door options.

Why it made the shortlist

The FOGATTI InstaShower 7 is a propane tankless water heater listed at 2.5 gallons per minute and 48,000 BTU, with staged combustion and anti-scale protection. It has a high-altitude mode to 9,800 feet, a preinstalled 150 PSI valve and a 6.6 foot smart remote.

Compared with the InstaShower 8 Plus, it has less BTU and costs less.

What works

  • States 2.5 GPM and 48,000 BTU
  • High-altitude mode to 9,800 feet
  • Three door options in two colors
  • Preinstalled 150 PSI valve

Watch out for

  • GPM figure lacks a stated temperature rise
  • Needs 12V control power
Check price on Amazon for FOGATTI InstaShower 7 RV Tankless Water Heater (opens in a new tab)
04

Best Premium Tankless · 4 of 6

FOGATTI InstaShower 8 Plus RV Tankless Water Heater

FOGATTI InstaShower 8 Plus RV Tankless Water Heater
  • 55,000 BTU propane
  • 12V DC, high altitude
  • 13 x 13 inch opening
Check price on Amazon for FOGATTI InstaShower 8 Plus RV Tankless Water Heater (opens in a new tab)
Best for: Larger households

Our take

Best for large families wanting more output.

Why it made the shortlist

The FOGATTI InstaShower 8 Plus is a propane, 12V DC tankless water heater with 55,000 BTU, listed for altitudes up to 9,800 feet. The opening is 13 by 13 inches and it is said to replace all RV water heaters.

What works

  • 55,000 BTU burner for higher output
  • High-altitude suitability to 9,800 ft
  • 13 by 13 inch opening fits many cutouts
  • Hot water lasts longer than a tank

Watch out for

  • Needs 12V DC power
The catch
Versus the InstaShower 7, it adds BTU and costs more.
Check price on Amazon for FOGATTI InstaShower 8 Plus RV Tankless Water Heater (opens in a new tab)
05

Best High-BTU Tankless · 5 of 6

ORBEK RV Tankless Water Heater

ORBEK RV Tankless Water Heater
  • 60,000 BTU propane
  • 12V DC power
  • Oxygen-free copper exchanger
Check price on Amazon for ORBEK RV Tankless Water Heater (opens in a new tab)
Best for: High-output on a budget

Our take

Best for buyers who want high BTU on a budget.

Why it made the shortlist

The ORBEK RV Tankless Water Heater is a propane unit with a 60,000 BTU burner and 12V DC power. It lists oxygen-free copper heat exchangers, brushless DC fans, a high-altitude mode and optional black or white door panels.

Compared with the FOGATTI InstaShower 8 Plus, it states more BTU at a lower price.

What works

  • 60,000 BTU burner
  • Oxygen-free copper heat exchangers
  • Optional door panels in black or white
  • Standard NPT water connections

Watch out for

  • Door panels sold separately
  • Needs 12V DC power
Check price on Amazon for ORBEK RV Tankless Water Heater (opens in a new tab)
06

Best Budget Tankless · 6 of 6

MapleGrace RV Water Heater

MapleGrace RV Water Heater
  • 55,000 BTU, CSA certified
  • LED display, touch panel
  • Dual outlets, exterior use
Check price on Amazon for MapleGrace RV Water Heater (opens in a new tab)
Best for: Budget tankless

Our take

Best for budget tankless buyers who want a CSA mark.

Why it made the shortlist

The MapleGrace is a 55,000 BTU propane tankless water heater that is CSA certified, with a digital display and touch panel. It has dual outlets, including an exterior outlet for outdoor use.

Versus the ORBEK, it states CSA certification, which is a plus for safety, and costs less. Versus the FOGATTI InstaShower 7, it lists higher BTU.

What works

  • CSA certification stated
  • Digital display with touch control
  • Dual outlets for exterior use

Watch out for

  • Fit and cutout details are thin
  • Needs 12V control power
Check price on Amazon for MapleGrace RV Water Heater (opens in a new tab)

Methodology

How We Built This Shortlist

Each pick was assessed across 5 criteria weighted for real-world use.

01

Heater type

We separated 6-gallon tank units from propane tankless heaters because capacity and installation differ.

02

BTU and flow context

We noted BTU and GPM, and flagged flow figures that lack temperature rise.

03

Power needs

We checked 12V DC and 120V requirements.

04

Fit and cutout

We compared named opening sizes and door options.

05

Safety marks

We looked for named certifications such as CSA.

Decision guide

Match an RV Water Heater to Your RV

By Household Size

Your situationRecommended pickWhy
One or two people, short showersSuburban SW6D6 gallons covers short showers.
Want gas and electricSuburban SW6DEAdds an electric element.
Family, long showersFOGATTI InstaShower 8 Plus55,000 BTU tankless.
Highest BTUORBEK 60K60,000 BTU propane.
Budget tanklessMapleGrace 55KCSA certified at a lower price.

By Budget

BudgetRecommended pick
$140 to $250MapleGrace 55K or ORBEK 60K
$410 to $440FOGATTI InstaShower 7 or Suburban SW6D
$500 to $520Suburban SW6DE or FOGATTI InstaShower 8 Plus

Tank vs Tankless

Tank

The Suburban SW6DE and Suburban SW6D store 6 gallons and heat slowly, but are simple and have fewer power needs. They suit short showers.

Tankless

The FOGATTI InstaShower 7, FOGATTI InstaShower 8 Plus, ORBEK 60K and MapleGrace 55K heat on demand and need 12V power. They suit long showers and give more usable space.

Most owners with a Suburban cutout should choose the Suburban SW6DE unless the FOGATTI InstaShower 7 conversion appeals.

By Installation

InstallRecommended pick
Existing Suburban openingSuburban SW6D
13 by 13 inch cutoutFOGATTI InstaShower 8 Plus
Door color choiceFOGATTI InstaShower 7
Black or white panelORBEK 60K

For High-Altitude or Cold-Weather Camping Specifically

Look for

A stated altitude rating, a freeze protection note and a 12V supply that stays charged, as the Suburban SW6DE listing shows.

In this comparison

The FOGATTI InstaShower 7 and FOGATTI InstaShower 8 Plus list a 9,800 foot altitude mode. Check freeze protection separately.

When to Spend More

Spend more if

Spend more on the FOGATTI InstaShower 8 Plus or Suburban SW6DE if you want higher output or dual fuel and expect heavy daily hot water use.

Save if

Save with the MapleGrace 55K or Suburban SW6D if you want a lower-cost fix and can accept limits.

FAQ

Before You Bring One Home

Do tankless RV water heaters need 12V power?

Many do. The FOGATTI InstaShower 7 and ORBEK 60K list 12V DC. Confirm your battery can supply it.

How do I know a tankless heater will fit my cutout?

Measure the opening and compare it to the listing, such as the 13 by 13 inches on the FOGATTI InstaShower 8 Plus. Check the door options.

Is the FOGATTI InstaShower 8 Plus worth more than the FOGATTI InstaShower 7?

If you want 55,000 BTU and higher output, yes. For lighter use the InstaShower 7 costs less.

How should I maintain an RV water heater?

Flush the tank, check the anode rod on a Suburban, and descale tankless units. Drain before freezing weather.

Can I replace a tank heater with a tankless?

Often yes, with the right cutout and gas supply. Follow installation rules and have a qualified person check venting.

Bottom line

The short version

Browse more rv water heater on Amazon →
Bowen Higgins, RV Editor at RV Gear Lab

About the author

Bowen Higgins

RV Editor at RV Gear Lab

Bowen covers RV power, water systems, towing and leveling, upkeep and interior comfort, with a focus on matching gear to the rig, the hookups and the way you actually travel.

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