Published 01-07-2021
| Article appears in August 2021 Issue

Clean, green Duoetto 10L water heater attracts RV and boating enthusiasts

Below: Jay King with his 12V/240V Mk 2 Duoetto, which is used globally on land and sea.

An Australian manufacturer’s 12V/240V water heating innovation is finding new markets locally and globally among global RV, marine and work vehicle markets.

Its clean, green performance cuts fossil fuel pollution in pristine places and emits no carbon monoxide or other hazardous and flammable gases in confined spaces.

The Duoetto MK2 12V/240V 10-litre water heater from Aus J Hot Water Solutions – globally­-available to individuals and OEMs through – builds on the local and international success of the first model in enabling people to enjoy civilised home comforts wherever they are, on the road or on the water. More than 30,000 Aus J heaters have been sold globally, including to OEMs in Australia, Europe and the US.

“One thing that has taken us pleasantly by surprise is the increasing degree of interest from both OEMs and individual users concerned about the hazards of different types of heaters posed for children, animals and remote area travelers themselves, who prize the pristine local environments into which they are adventuring in the emerging post-Covid local travel boom,” says Aus J Managing Director, Jay King.

Mr King says the tough, Australian-designed compact and durable water heater offers selectable temperatures between 30-75 deg C on 240V so people can shower, wash, clean and enjoy abundant hot water whether mains power is available or not and without them having to store and carry additional fossil fuels.

“We make many types of heaters, including the Duoetto, so we are not singling out particular types of heaters as being bad. Some of the alternatives are very good and do a magnificent job of heating lots of water quickly, so it is horses for courses.

“But there is always pollution with fossil fuels and a risk of carbon monoxide when you sleep in a room where a conventional coal or gas fire, a log burner, a cooker, a water heater, or a back-burner leaks. You cannot feel the early symptoms of carbon monoxide, so some people feel it is important to protect their children, their pets and themselves.

“Others just like the pollution-free performance,” said Mr King, whose latest heaters feature a digital temperature control on the side of the heater, which is now being exported to markets including the Middle East and Asia, North America, Africa and Europe, including the UK.

“Automatic sensors allow switching to 12V when mains power is not available, enabling the Duoetto to deliver ample hot water in remote areas such as campsites or on boats,” says Mr King.

“The latest Duoetto MK2 is especially suited to caravans, equestrian transport, campervans, yachts, motorhomes and a huge range of recreational vehicles. When you’re on the road or out on the water, readily available hot water is a real luxury,” said Mr King.

“We get some people saying, ‘But what about the water heater’s current draw on a battery,’ and it is true that the heater will draw more amps when it is doing its job compared with, say, a refrigerator. But what they forget (and what OEM manufacturers know) is that it does this only for a brief period, as water temperatures rise by about a degree a minute above ambient levels.

“So even though the current draw sounds a lot, compared with 1.5 amps an hour from a refrigerator, for example, the point is that the fridge is on for 24 hours and draws far more amps overall. We have OEM customers in the US, Africa and Australia who sells their products into diverse markets and it is not a real problem. They stake their reputation on it.

“And what is happening as we emerge from Covid is that more people are travelling in their own countries and are learning how important it is to protect their natural environments from pollution. I think this is really creating environmental awareness benefits for us.”

Upgrades on previous versions

The Duoetto MK2 has a number of upgrades on the previous version, improvements designed to give the new water heater even greater quality, durability and longevity than the original.

The latter has become OEM equipment on major campers in Australia and in export markets including South Africa and the US because of its functionality and reliability in service over a wide range of use and climatic conditions. Upgrades include:

  • An Incoloy 840 heating element, which gives superior corrosion resistance and is designed for optimum use in extreme environments and temperatures.
  • A single weld line tank for a sturdier construction, reduced water leakage and extended product life.
  • Polyurethane insulation to maintain temperatures and reduce energy consumption. This is an environmentally harmonious CFC-free material.
  • SPCC steel and enamel tank for improved corrosion resistance
  • Digital temperature control for ease of control and readability, fully adjustable from 30-70 deg C

The Duoetto MK2 comes with internationally recognised Australian WaterMark accreditation, which means that it passed tests and requirements regarding its suitability for supplying water for human consumption. These tests encompass taste, smell, toxins and corrosive effects on plumbing and pipework.

Drawing a miniscule 4.2 amps at 240V (1000w) and 25 amps at 12v (300w), the 409 x 262 x 267mm Duoetto MK2 retains the strengths of its predecessor, including:

  • Manufactured to Australian Standard AS/NZS 3350.1.1:2002 and with WaterMark certification to Australian Standard AS/NZS 3498:2009
  • Adjustable thermostat on 240V up to 75deg C
  • Durable outer case with service and inspection points
  • The water heater connects to 12V DC power supply meaning there is no need for a generator, inverter or 240V power supply.
  • Integrated magnesium sacrificial anode protects against galvanic corrosion and extends the life of the water heater.
  • Thermal cut-out
  • Over-heat protection
  • Combination brass pressure relief valve
  • Warranty 12 months




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