Australia's most advanced range of Solar Hot Water and Heat Pump Hot Water Systems Australia, New Zealand and the South Pacific

Envirosun AS Split Solar

Envirosun AS split solar hot water systems

Envirosun Brisbane, Envirosun Sydney, Envirosun Gold Coast, Envirosun Sunshine Coast, Envirosun Newcastle

Australian made solar hot water cylinders with storage tank sizes to suit all homes and climates, + 100% Australian owned

The benefits of using the sun’s energy to heat water has been around for many decades, Envirosun have developed the most advanced split solar hot water systems in Australia.  The Envirosun AS solar hot water range is designed exclusively for the vast Australian climate and varying conditions.  Envirosun AS solar hot water heaters are in a class of it’s own when it comes to performance, reliability and life expectancy.  From the Australian made solar hot water storage tanks, to the best European control and pumping systems along with the extremely high solar absorption panels made from the absolute pinnacle of  solid materials copper, aluminium and brass, Australian Valve Group safety and control valves, when all this is applied together gives the Envirosun AS range of solar hot water systems the reputation it clearly deserves.

Add the generous warranties offered and the fact that Envirosun is 100% Australian owned,  makes it a clear smart decision to install an Envirosun solar hot water system

Below is a bit of technical talk about the Envirosun AS split solar hot water heater range

The AS Solar Storage tank

Solar hot water systems Brisbane

Our storage cylinder built to last 

Envirosun TS tanks are fabricated from high-strength materials especially suited to operating in high-temperature, high-pressure applications which can otherwise be very corrosive. And for added life our TS Plus tanks exclusively incorporate 444 stainless steel internal pressure vessels. To learn about our 444 stainless steel tanks, read: our stainless steel.

Our hot water tanks stay hotter for longer

Envirosun cylinders are encapsulated in a pressure-injected, high-density polyurethane thermal insulation. Compared with archaic insulation systems using straw, wool or fibreglass, polyurethane retains more heat and does so for far longer – and it has the added advantage of imparting structural rigidity to the assembled vessel. To find out how polyurethane is used to create a superior thermal barrier, read: our insulation.

Our storage cylinders deliver hot water faster

Our storage cylinders deliver hot water faster Our solar hot water systems are rated to operate high water pressures that are near to that of the mains water supply. Unlike low pressure hot-water systems, you can enjoy plenty of hot-water from more than one outlet at the same time. To understand how our system of pressure control valves works to limit but maintain hot-water system pressure, read: our pressure valves.

Envirosun systems use this mix of optimisation and over-temperature protection functions to maximise energy savings and minimise heat stresses.

the brains behind the Envirosun AS solar

Resol deltasol solar hot water conrollers

Inside the Envirosun control panel is the most advanced Resol Deltasol controller

This Envirosun multiprocessor controller is the brains that makes the solar work and it also displays everything that is going on its LED screen
Only the highest quality German made solar hot water controllers are used in Envirosun AS solar hot water systems

Envirosun solar hot water is pumped by the European made Salmson solar pump

Envirosun trust all the hard work of circulating the hot water through the solar panels to these proven little beauties.
Made in France to the highest quality and engineering, they are also used by most of the major brands in Australia

the hard work is trusted to

Envirosun use Salmson solar hot water pumps

safety and control valves

AVG solar valves are used in Envirosun solar hot water systems

Envirosun use AVG, Australian Valve Group valves

All of the Envirosun's AS solar hot water systems come with the valves needed when installing them.
Choosing the right valves to protect our solar hot water systems and your family is a very important job and we have entrusted that job to the Australian Valve Group , AVG



Envirosun solar hot water systems are equipped with either electric boosters that can also have Natural or LPG gas boosters added to ensure that there’s plenty of hot-water available during the worst weather or when the demand for hot water is high. Electric elements are fitted inside our storage tanks and the gas instantaneous heaters can be installed in-line from the outlet of our systems. Both options are designed to maximise the amount of solar energy that can be collected and utilise the auxiliary in a ‘back-up’ or ‘booster’ mode only.


Electrical assisted systems are integrated arrangements that comprise a heating element immersed in the storage tank water, controlled by a thermostat and connected to a power-supply. Both the element and thermostat are positioned at the midpoint of the tank . With the power-supply on, if the temperature at the centre of the tank falls below 60°C, the thermostat ‘closes’ and the heating element operates. The element continues to operate until the mid-point of the tank rises to above 60°C. The location of the element and thermostat in an Envirosun system are designed to only allow the booster to only heat the water in the top half of the tank and to leave the bottom portion available for useful solar gain. Our solar hot water systems have the ability to heat water without direct sunlight to approximately 2 x the ambient air temperature, for instance if it is a overcast day and the outside temperature is 22 degC  for most of the day, your solar should be able to get the water to around 44 degC


Gas boosted systems involve a continuous-flow gas water heater that is mounted separate from the storage tank. The outlet from the solar hot water system is piped as the inlet to the gas heater. If the water reaches the gas heater at a temperature below 60°C, the gas supply is opened, the spark-ignition system fires, and the gas burner operates. If the inlet water temperature is above 60°C, the gas heater does not operate.

Envirosun systems use this pre-heater configuration to achieve higher solar contribution and significantly lower greenhouse gas emissions

Up To +80% Cheaper

*Based on power charged at $0.30 kWh

why the Envirosun "as" system is better solar water heater

Check out some of the comparisons here on different heat pump hot water heater brands and the Australian Government tested and allocated STC rating, the STC is a rated saving that a hot water system has been granted after testing and approved by the  Australian Clean Energy Regulator,  the number of STC’s that are issued refers to one megawatt hour (1 MWh) of avoided energy consumption over the heat pump hot water system’s deemed life expectancy

S =  R – T  where: S: STC count  R: Reference conventional system’s energy consumption (MWh over ten years) T: Tested system’s estimated energy consumption (MWh over ten years)

Here is a graph showing savings and ratings of STC assigned to some brand and the approximate percentage of power saving  compared to a conventional electric water heater in zone 3 

Renewable Energy Target | Tindo Solar

Envirosun AS 315/50 Solar hot water systems receives 40 STC
Envirosun 87%
Dux 315lt 2P solar hot water systems receive 39 STCs
Dux 85%
Rinnai 315lt Sunmaster Solar hot water systems receives 36 STC
Rinnai 75%
Chromagen 300 Solar hot water systems receives 33 STC
Chromagen 70%
Solahart 325 Split Solar hot water systems receive 30 STC
Solahart 30000 kWh savings 65%
Rheem 325 Solar hot water systems Lowline receives 30 STC
Rheem 30000 kWh saving 65%
Envirosun solar hot water systems have a 7 year warranty
Envirosun Split solar water heaters
Envirosun As Solar Hot Water System Brochure
Envirosun solar hot water is Australian owned
Our other Envirosun and Enviroheat water heating products
Envirosun TS Plus stainless steel solar water heaters
Click here for the Envirosun TS Plus Solar Hot Water System
Enviroheat heat pump water heaters Australia
Click here for the Enviroheat Heat Pump Hot Water System

The AS “active solar”  Envirosun Solar Hot Water Heaters are also known as the split solar hot water system, they offer greater flexibility, improved aesthetics for your home and a larger hot water storage tank capacity

These solar hot water systems only require the solar panels to be installed on the roof with the hot water storage tank located at ground level or any other convenient location throughout the home.  Envirosun AS solar hot water system are relatively simple in operation – when the solar hot water panels (also known as solar collectors) are able to add heat into the storage tank, a small pump is switched on to circulate hot-water from the collectors and replace it with cool water from the tank. 

 The circulation pumps are relatively small and silent, they also draw a negligible amount of power (less than 28 watts) that is also only used when operating or needing solar to increase the hot water storage cylinder’s temperature.   

When the collectors are 6°C hotter than the water in the storage tank, the circulating pump is operated. When the differential falls to 4°C or lower, the pump is not operated. The microprocessor also uses the sensor information to control a suite of over-temperature protection modes:

  • if the water in the Envirosun storage tank reaches 70°C, the solar pump is not operated

  • if the solar collector panels temperature reaches 190°C, the pump is cycled on to control the temperature to below 185°C therefore protecting the solar panels

  • if the solar panels temperature reaches 200°C the pump is not operated to prevent damage

  • if the tank temperature has risen above 70°C and the collectors are cooler the pump is run intermittently to protect the storage tank from damage and overheating 

The Envirosun AS smart control system is absolute state of the art with a LED screen to tell you exactly whats going on inside our weatherproof cover 

Split solar hot water systems Brisbane, Sydney, Melbourne
How the Envirosun AS split solar hot water system works
Envirosun's AS solar hot water heater range are available in 3 different storage tank sizes to suit any home AND all are Australian made