You want the convenience of hot water for showering and dishwashing on the go β but how do you know which caravan hot water system is right for your setup? Should you go for a 12V water heater that's gentle on the batteries, or a 240V unit that heats faster?
When choosing a hot water system for your campervan, caravan, RV or boat, you must look beyond cost. In fact, cost should be the last consideration. Prioritise construction quality, heating power, tank capacity and power compatibility first β and that's exactly how we've ordered the 12 factors in this guide.
What Is a Storage Hot Water System (and Why Caravanners Choose Them)?
A water heater β or hot water system, as the caravanning community calls them β heats cold water to your desired temperature, powered by electricity (AC, DC or both), gas or diesel. Electric and gas systems come in two main types:
Tankless (instantaneous) water heaters heat water only when you open the hot tap β cold water flows in, gets heated instantly, and flows out.
Storage (tank) water heaters hold water in an insulated tank where a heating element warms it and keeps it ready for use.
Both have their place, but storage models are the most common choice for off-grid use in caravans, campervans, RVs and boats, thanks to better energy efficiency in intermittent-use scenarios and a typically lower upfront cost.
What About Point-of-Use Water Heaters?
A point-of-use (POU) water heater is a compact unit installed right where the hot water is needed β under a sink, in a cabinet, or by the shower enclosure. They're popular in caravans because short delivery pipes mean near-instant hot water and minimal heat loss. The simple Aqueous 6L 12V and the more sophisticated Duoetto MK2 are perfect examples.
The 12 Factors for Choosing a Caravan or Campervan Hot Water System
1. Your hot water needs
Start by assessing how much hot water you actually use, and for how many people. This determines everything downstream β capacity, power, and mounting location.
Takeaway: Our hot water range covers single and multiple users, in both low-voltage and high-voltage options.
2. Size and weight
Make sure the unit physically fits your intended mounting spot, and factor in its weight when full so it stays stable and safe once mounted.
Takeaway: Our storage water heaters fit comfortably under a standard sink or inside a cabinet, weighing just 6.1β7.4Β kg empty.
3. Build quality and durability
Choose a well-made unit that won't fail after a few trips β that means quality construction materials and exceptional welding.
Takeaway: Ours feature a high-impact plastic housing, single-weld steel tank, premium nickel-based heating element, glass-like enamel coating and a magnesium anode rod against rust and corrosion.
4. 12V or 240V: power compatibility
Match the heater to your van's power system: a 12V DC water heater is gentle on the battery bank, while a 240V AC version heats faster on shore power or an inverter. Our range includes:
- Aqueous 6L 12V β 12V DC
- Aqueous 6L 240V β 240V AC
- Aqueous MK2 10L 240V β 240V AC
- Duoetto MK2 10L β dual 12V DC / 240V AC
5. Adjustable thermostat
A variable thermostat lets you heat water to exactly the temperature you want β look for settings comfortably above body temperature (37Β°C).
Takeaway: All our tank water heaters adjust from 30Β°C to 75Β°C. At 75Β°C the water is hot enough that you'll mix it with cold for a comfortable shower.
6. Heating element power rating
Higher wattage means faster heating β but also a bigger draw on your power source. 12V models run lower wattage deliberately, to protect your battery bank.
| Model | Element rating | Power requirement |
|---|---|---|
| Aqueous 6L 12V | 180W | 12V DC (15A) |
| Aqueous 6L 240V | 1000W | 240V AC (4.2A) |
| Aqueous MK2 10L 240V | 1000W | 240V AC (4.2A) |
| Duoetto MK2 10L 12V/240V | 300W / 1000W | 12V DC @ 25A or 240V AC @ 4.2A |
7. Tank capacity
The larger the tank, the more people it supports per heating cycle. Space is at a premium in a van, so size it to your real needs.
Takeaway: Heated to 75Β°C, a 6-litre tank delivers up to 18 litres of comfortable warm water once mixed β enough for an extended shower. A 10-litre model provides 30+ litres, enough for multiple hot showers.
8. Insulation
Off-grid, you can't afford to keep reheating water. Good insulation keeps already-heated water hot for hours.
Takeaway: Our heaters use high-density closed-cell polyurethane insulation with a high R-value and an airtight seal β which also adds protection against corrosion.
9. Power efficiency and battery draw
Here's the part most buyers get wrong: the energy needed to heat a tank depends on the amount of water, not the element's wattage. Heating a full 10-litre tank from 20Β°C to 75Β°C takes about 639Β Wh whether the element is rated 300W or 1000W β the wattage only changes how fast it gets there.
Takeaway: Our range spans low-draw 180W models through to 1000W versions. The Duoetto MK2 is the standout hybrid, switching between 300W (12V) and 1000W (240V) operation.
10. Built-in safety features
Look for protection against over-pressure, over-temperature, rust, corrosion and electrical faults.
Takeaway: All our storage water heaters include a pressure relief valve, over-temperature protection and multiple safeguards against rust and corrosion.
11. Warranty support
A solid warranty is proof the company trusts its own product β and peace of mind for you. It's often better to pay a little more for a unit backed by someone who'll answer the phone.
Takeaway: Our systems are tested for Australia's harsh conditions, are the same units we run ourselves, and come with a 12-month warranty and the friendliest return policy in the country.
12. Price β last, not first
Once you've shortlisted units that tick every box above, then compare prices. Starting with price is how buyers end up with leaks, poor heating, discoloured water and rust.
Takeaway: Our most affordable models start at $390 including the unit, installation components, warranty support and all the features above.
DIY or Professional Installation?
The hot water systems we stock are point-of-use models, so installation is straightforward: gather your tools, plan the plumbing route, and confirm your power source. If you're not comfortable with plumbing and electrical work, a professional install shouldn't cost much β and buys you a clean, leak-free system with no short circuits.
Caravan Hot Water System FAQ
Can you run a caravan hot water system on 12V?
Yes. 12V water heaters like the Aqueous 6L 12V (180W) or the Duoetto MK2 in 12V mode (300W) run straight off your battery bank β they just heat more slowly than 240V units and draw 15β25A while running.
How much battery does it take to heat a tank of water?
Roughly 639Β Wh to take a 10-litre tank from 20Β°C to 75Β°C β about 53Ah from a 12V battery bank. A 6-litre tank needs proportionally less. Good insulation means you won't reheat often.
Storage or instantaneous β which is better for a caravan?
For off-grid use, storage (tank) systems usually win: they suit intermittent use, sip power more predictably, and cost less upfront. Instantaneous units shine when you have unlimited power or gas and want endless hot water.
What size hot water system do I need?
For one or two people, a 6-litre tank (up to ~18 litres of warm mixed water) covers showers and dishes. For families or longer showers, step up to a 10-litre model (30+ litres of warm mixed water). Browse the full hot water range here.
