5 Best RV Solar Hot Water System Options for Off-Grid Travel (2026)

By Audrey Hayes

Updated November 2026

Choosing an rv solar hot water system comes down to how you travel, how much roof and battery capacity you have, and whether you want a fixed setup or a portable kit you can take off the rig. This list focuses on five products that fit different needs, from a controller for a pressurized solar loop to portable propane and circulation pumps that work alongside solar heat. Selection was based on published specifications, the manufacturer’s stated use case, brand reputation in the RV and off-grid community, and recurring patterns in owner feedback. We did not test these products ourselves, so verify compatibility with your rig before buying.

Our Top Picks

Quick Comparison

MISOL 110V Controller of Solar Water Heater, Used for Separated pressurized Solar hot Water System

MISOL 110V Controller of Solar Water Heater, Used for Separated pressurized Solar hot Water System

View on Amazon

Best for: Pressurized solar hot water loops with a separate storage tank.

This is a controller rather than a heater, so it suits owners who already have or plan to build a solar collector and tank and want automatic pump control based on temperature difference. It fits fixed installations, such as a roof-mounted system on a larger motorhome or a trailer with a dedicated solar loop.

Key specs:

• Designed for separated, pressurized solar hot water systems
• 110V controller type, per the listing name

Pros:

• Purpose-built for solar loop control, not a general-purpose timer
• Works with separated pressurized configurations
• Fits a standard “set it and forget it” workflow once wired

Cons:

• Requires 110V power, which may not suit off-grid rigs without an inverter
• Needs a compatible sensor setup and some electrical knowledge to install

Bottom line: Best for owners with a pressurized solar loop who want automatic control and have access to 110V power.

View on Amazon

CAMPLUX Portable Propane Water Heater & Pump Kit, 1.32 GPM Tankless Gas Shower System

CAMPLUX Portable Propane Water Heater & Pump Kit, 1.32 GPM Tankless Gas Shower System with 12V Pump, Long Power Cables & Extension Hoses, Instant Hot Water for Off-Grid Camping, RV, AY132P43, White

View on Amazon

Best for: Off-grid camping with propane backup on sunny-deficient trips.

This kit suits travelers who want instant hot water without relying solely on sunshine. It works well as a backup to a solar setup on cloudy stretches or in winter, and its 12V pump makes it practical for showers and dishwashing away from hookups.

Key specs:

• 1.32 GPM tankless output
• 12V pump included
• Propane-fired, with long power cables and extension hoses per the listing

Pros:

• Instant hot water without a storage tank
• Includes pump, cables and hoses in one kit
• Useful as a reliable backup when solar output drops

Cons:

• Uses propane, so fuel supply and ventilation need attention
• Flow rate is modest for multiple simultaneous outlets

Bottom line: Best for campers who want propane backup to pair with solar, especially in variable weather.

View on Amazon

CAMPLUX Portable Tankless Water Heater, 1.32 GPM 5L Propane Water Heater

CAMPLUX Portable Tankless Water Heater, 1.32 GPM 5L Propane Water Heater for Camping, RV & Off-Grid, Instant Outdoor Hot Water Shower System with Gas Regulator, Battery Powered, AY132G, Gray

View on Amazon

Best for: Compact rigs and small kitchens where space is tight.

A smaller, battery-powered tankless unit suits van and small trailer owners who need hot water at a sink or shower without installing permanent plumbing. It pairs well with a solar pre-heat setup or as a standalone supplement.

Key specs:

• 1.32 GPM output
• Propane fuel with gas regulator
• Battery-powered ignition, per the listing name

Pros:

• Compact footprint for small spaces
• Battery operation simplifies setup
• Instant output with no storage tank

Cons:

• Propane dependence limits the pure-solar goal
• Output is best suited to one outlet at a time

Bottom line: Best for van and small-trailer owners who want a portable, space-saving hot water option.

View on Amazon

Spotless Water Systems DIC-10, Simple Window, Solar Panel, RV & Car Wash System

Spotless Water Systems – DIC-10, Simple Window, Solar Panel, RV & Car Wash System, Works for All Vehicles, Motorcycles, Bikes, Boats, Planes, Yachts, Towel Drying Eliminated

View on Amazon

Best for: Exterior rinsing and washing of the rig, boat or bike.

This is a solar-panel-powered wash system rather than a domestic hot water source. It suits owners who want to wash the RV without using rig water tanks, and it is a useful companion to an rv solar hot water system if you want solar energy handling exterior cleaning too.

Key specs:

• Solar panel powered, per the listing name
• Designed for RVs, cars, motorcycles, boats and similar vehicles

Pros:

• Uses solar power directly for washing
• Reduces demand on freshwater tanks for exterior cleaning
• Works across many vehicle types

Cons:

• Not intended for hot water in the living space
• Performance depends on sunlight and panel orientation

Bottom line: Best for owners who want a solar-powered exterior wash system rather than indoor hot water.

View on Amazon

for Hot/Cold Water Circulation System, RV Water Heater, Pool Heating & Homebrew Wort Transfer, 3.5 GPM 19.6 FT Lift 12V DC Solar Water Heater Circulation Pump

for Hot/Cold Water Circulation System, RV Water Heater, Pool Heating & Homebrew Wort Transfer, 3.5 GPM 19.6 FT Lift 12V DC Solar Water Heater Circulation Pump, Mini Inline Water Pump

View on Amazon

Best for: Moving water through solar loops and circulation runs.

A 12V DC circulation pump suits builders assembling their own solar loop or adding circulation to an existing collector. Its listed flow and lift make it relevant to rooftop and under-chassis runs, though it is not a heater on its own.

Key specs:

• 3.5 GPM flow rate
• 19.6 ft lift
• 12V DC operation

Pros:

• 12V DC fits RV electrical systems directly
• Listed lift suits typical rooftop-to-tank heights
• Versatile for solar and other circulation tasks

Cons:

• Requires a separate collector and tank to heat water
• Not all listing claims are verifiable without the seller’s full spec sheet

Bottom line: Best for DIY builders who need a 12V circulation pump to move water through a solar loop.

View on Amazon

Buying Guide

Heating Method: Pure Solar vs. Solar With Backup

Decide first whether you need pure solar or solar with a fuel backup. A pure solar setup depends on collector area and sunshine, while a backup handles cloudy days and winter. Owners often report that propane backup is the difference between comfortable and marginal hot water on long trips.

Good picks for this: CAMPLUX Portable Propane Water Heater & Pump Kit, CAMPLUX Portable Tankless Water Heater

Controls and Pumping

A pressurized or separated solar loop typically needs a controller and a circulation pump. Check that the controller matches your loop type and voltage, and that the pump’s flow and lift suit your roof-to-tank height.

Good picks for this: MISOL 110V Controller of Solar Water Heater, 12V DC Solar Water Heater Circulation Pump

Electrical Compatibility

Most RVs run 12V DC on the house battery bank, with 120V AC available only at hookups or through an inverter. Match each component to the voltage you can supply, and factor in battery capacity for pump runtime.

Good picks for this: 12V DC Solar Water Heater Circulation Pump, MISOL 110V Controller of Solar Water Heater

Size and Fit

Measure the space for the tank, heater and collector before buying. Compact units suit vans and small trailers, while larger systems need roof or underbody room. Check hose lengths and fitting sizes against your existing plumbing.

Good picks for this: CAMPLUX Portable Tankless Water Heater, CAMPLUX Portable Propane Water Heater & Pump Kit

Flow Rate and Simultaneous Use

Flow rate determines how many outlets you can run at once. Units rated around 1.3 GPM typically handle one shower or sink comfortably. If you want two outlets at once, look for higher flow or stage your use.

Good picks for this: CAMPLUX Portable Propane Water Heater & Pump Kit, 12V DC Solar Water Heater Circulation Pump

Durability and Weather Exposure

RV components face vibration, road dust, temperature swings and occasional rain. Look for enclosed electronics, sealed fittings and components rated for outdoor use. Mount exposed parts where they are shielded from direct road spray.

Good picks for this: Spotless Water Systems DIC-10, MISOL 110V Controller of Solar Water Heater

Care and Maintenance

Drain and winterize the system before freezing weather, flush sediment from the tank periodically, and inspect hoses and fittings for wear. Propane units need regular checks of regulators and burner areas.

Good picks for this: CAMPLUX Portable Tankless Water Heater, 12V DC Solar Water Heater Circulation Pump

FAQ

Can an rv solar hot water system work without any sunshine?

No. A solar-only system depends on sunlight to heat the collector and tank. In cloudy weather or at night, you need a propane or electric backup, or you simply go without hot water until sun returns.

Do I need a controller for a solar water heater on an RV?

For a pressurized or separated solar loop with a pump, a controller is strongly recommended. It starts the pump when the collector is hotter than the tank and stops it when the temperature difference falls, which protects efficiency and equipment.

Is a 12V pump enough for an RV solar loop?

Often yes, if its flow rate and lift match your collector and tank layout. Check the listed lift against the vertical distance from the pump to the highest point of the loop, and verify that the pump’s power draw fits your battery bank.

Can I use propane water heaters with solar?

Yes. Many owners use a propane heater as a supplement when solar output is low. Keep ventilation, carbon monoxide detection and fuel regulator checks in mind, and follow the manufacturer’s installation instructions.

Is an exterior wash system the same as an rv solar hot water system?

No. Exterior wash systems use solar power for cleaning the outside of the vehicle, while an rv solar hot water system heats water for showers, sinks and other indoor use. They can complement each other but serve different purposes.

Should I hire a professional to install an rv solar hot water system?

For gas lines, roof penetrations and electrical work, consult a qualified RV technician or licensed installer. Improper gas or electrical wiring can cause fire, carbon monoxide or water damage.

Conclusion

For a pressurized solar loop with automatic control, the MISOL controller is the logical starting point, paired with a 12V circulation pump such as the DC model listed above. Travelers who need hot water on cloudy days should consider the CAMPLUX propane kit as a backup, while the compact CAMPLUX tankless unit suits small vans. The Spotless DIC-10 is a solar-powered exterior wash option rather than an indoor hot water source. Match the pick to your rig’s voltage, space and how often you expect to rely on sun versus fuel.

Sources

• Guidance on solar water heating principles, system types and efficiency considerations (energy.gov)
• Codes and safety standards for propane and fuel-gas appliances in recreational vehicles (nfpa.org)
• Standards and technical references for water heating and solar thermal system design (ashrae.org)

Related reading

• What's the Best Solar Hot Water System? 3 Top Picks Compared (2026)
• What Is the Cheapest Solar Hot Water System? Options and Trade-Offs
• Top 5 Solar Thermal Storage Tanks for Home Hot Water Systems
• Top 4 Service Solar Hot Water System Options Compared (2026)

About Audrey Hayes

Audrey Hayes is part of our editorial team and reviews and edits our solar water heaters guides, checking product details against manufacturer specifications and owner feedback.