Electric Hot Water Heaters
Electric hot water systems are the most commonly used type of water heaters in Australian households, and have been manufactured locally for over 100 years. While the technology has not changed significantly over time, improvements in insulation have resulted in better efficiency for electric hot water systems made prior to 2000.
Similar to a kettle with a heating element, electric hot water systems come in three different power ratings for the Queensland market – 1.8kw, 2.4kw, and 3.6kw. Although some areas have 4.8kw elements available, they are rare in Queensland due to their high power consumption. These power ratings are consistent across all brands, including Rheem, Dux, Vulcan, AquaMAX, and Rinnai.
The size of the element does not affect the energy rating of the hot water system. For example, a 1.8kw element will use half the power of a 3.6kw element but will take twice as long to heat the same amount of water to the same temperature. Electric hot water systems are made of mild steel tanks with vitreous enamel lining and protected by a sacrificial anode and stainless steel. Old copper-style water heaters are no longer available.
Electric hot water systems typically account for at least one-third of a household’s power bill when not using solar power. Any surplus solar power generated through a P.V. solar system can be sold back to the grid at a buy-back price, provided that the hot water system is connected to tariff 11, which is the general power and lighting supply for 24 hours a day at a higher rate. Solar power will not be able to power a hot water system if it is connected to tariff 33, which guarantees power for 18 hours a day, usually excluding 6pm-9pm and 6am-9am, or tariff 31, which provides power only during the lowest electrical grid demands, usually between 9pm and 6am.
Tariff 31 is not sufficient to power hot water cylinders smaller than 250 litres for two or more people. Electric hot water systems are available in tank sizes ranging from 25 litres for single sink applications to 400 litres. Please see below for approximate recommendations based on the number of people in the household.
There may be slight variations due to the amount of hot water used by occupants
50 litres & 80 litres = 1-2 people in a unit type home and only connected to tariff 11 and can not be connected to a off peak tariff to provide reliable hot water
125 litres = 2-3 people in a unit or small town house, when connected to tariff 33
160 litre = 2-4 people in a unit or small town house, when connected to tariff 33
250 litre = 2-4 people when connected to tariff 31 and is what is in most 3 bedroom homes built and up to 6 persons when connected to tariff 33
315 litre = 3-5 people when it is connected to tariff 31 and up to 7 persons on tariff 33
400 litre = 4-7 people when connected to tariff 31 and up to 9 people when it is connected to tariff 33 and 12 people on tariff 11
Brands of Electric Hot Water system available
Rheem is a well-established brand in the hot water heater industry, with over 100 years of experience in manufacturing water heaters. Their products are available in many countries and cater to both residential and commercial needs.
Rheem manufactures a wide range of electric hot water heaters in Australia, with their mild steel Vitreous Enamel (VE) range being produced in Sydney and their stainless steel products being made in Melbourne. They also have a number of well-known domestic hot water brands under their banner, including AquaMAX, Vulcan, and Solahart.
Rheem offers warranties that range from 5 to 12 years depending on the size and type of product, and requires servicing at least every 5 years to support the warranty and prolong the life of the hot water tank. This includes the changing of sacrificial anodes in the VE range and the recommended replacement of the pressure and temperature relief valve.
The AquaMAX brand has been in operation since 1988, indicating that it has been around for over three decades. The brand was a family-owned business until Rheem acquired it in 2009, making it part of a larger corporation.
At the time of Rheem’s acquisition, AquaMAX had already sold over 500,000 electric water heaters, indicating that it was an established player in the market with a significant customer base.
AquaMAX has always been known in the industry for its quality, especially with its stainless steel products.
The company still manufactures its stainless steel products in Victoria, indicating a long-standing manufacturing presence in the region or a preference for locally sourced materials. The mild steel VE electric hot water range is made in Rheem’s Sydney plant, indicating that the company has multiple manufacturing locations for its products.
The AquaMAX hot water range comes with warranties ranging from 7 to 10 years depending on the size of the cylinder. The smaller the cylinder, the shorter the warranty.
They require service prior to 5 years of use, especially changing the anode to help the tank last longer.
Vulcan Electric Hot Water Systems is another brand owned and manufactured by Rheem Hot Water Systems. Vulcan only produces its electric hot water range in the mild steel Vitreous Enamel style.
The Vulcan 50L Electric Storage Water Heater has a 7-year cylinder warranty, while the Vulcan Electric 80-litre to 400-litre models carry a 10-year cylinder warranty. To prolong the life of the cylinder, the anode needs to be changed between the 4th and 5th year of use. They are generally recognized as Rheem’s budget brand.
Rinnai has been a prominent name in the gas hot water industry for a long time, and until recently, they sourced their electric hot water range from China and/or Dux Hot Water Manufacturing in NSW.
However, Rinnai has recently opened its own manufacturing plant in Victoria for its Hotflo electric hot water systems. These systems come in various sizes, ranging from a small 25-litre system suitable for kitchenettes to a massive 400-litre system.
The warranties for Rinnai electric hot water systems are 7 years for the 25-litre and 50-litre systems, and 10 years for all sizes above that. However, to ensure the longevity of the systems and to uphold the warranty, they require a service within 5 years or sooner.
Dux Hot Water Systems has been operating in Australia for over 100 years and was Australian-owned until a few years ago.
Dux only produces its electric hot water systems with mild steel vitreous enamel lined cylinders. These water heaters are manufactured in Moss Vale, NSW, and China, with tank sizes ranging from 25 litres up to the 400-litre model.
The warranties for Dux electric hot water systems vary, with 7-year warranties for the cylinders of the 25-litre and 50-litre systems, and 10-year warranties for all sizes above that capacity. As with other mild steel hot water systems, they require sacrificial anodes, which need to be changed before the 5-year mark to ensure the system lasts and to uphold the warranty.
However, since Dux was sold, their reputation in the hot water industry has fallen from being Australia’s #2 brand to a point where no one wants to do business with them. They have managed to survive by supplying Bunnings and manufacturing the Therman brand for Reece Plumbing Supplies, as no other places bother to stock or sell the Dux brand anymore.
Thermann is an exclusive brand name for the Reece Plumbing Supplies chain, and Dux Hot Water in New South Wales and China manufactures it for smaller storage capacity heaters.
Thermann electric hot water systems are essentially the same as the Dux Proflo, except for the branding. They come in various storage sizes ranging from 25 litres to 400 litres and are made from mild steel with an internal vitreous enamel coating. Like other mild steel hot water systems, they have a sacrificial anode that protects the system from deterioration, which needs to be replaced within the 5-year period. They come with the same warranty periods as the Dux Proflo, with 7-year warranties for the cylinders of the 25 and 50-litre systems and 10-year warranties for all sizes above that capacity.
However, these electric water heaters are not remarkable, as they are simply a rebranded system from a brand that has lost its way in the industry. Dux has poor products, after-sales service, warranty, and very low care factor for consumers. Thermann water heaters are only available at Reece Plumbing Supply stores.
We offer Easy Payment Plans* for electric water heaters from all brands over 12 months. Contact Brisbane Hot Water Northside today for fast and reliable service at 1300 728 122.
We are also available after hours at 0413 861 166.