Solahart 302SP

Ideal for medium-sized households with reliable solar hot water performance.

The Solahart 302SP is designed for medium-sized households, combining high-capacity solar water heating with corrosion-resistant technology. With its closed-circuit thermosiphon system, it’s perfect for areas with harsh water conditions.

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Family size

300^L

Capacity (L)

Collectors

5^Years

Warranty

View detailed specs

Solahart 302SP Solar Water Heater: Key Attributes

Why the 302SP system is a smart choice

The Solahart 302SP is a solar hot water solution for medium-sized households of 3-5 people. Featuring a 302L tank, this system provides ample hot water while using closed circuit thermosiphon technology for superior corrosion protection, making it perfect for harsh water conditions. The system includes a TRV valve for safe operation and Super Shield Enamel for long-lasting durability. The SP Free Heat Series offers significant energy savings, with up to 80% reduction in water heating costs, all while reducing your carbon footprint.

Key Features:

Capacity: 300-Litre tank, ideal for medium households (3-5 people).
Closed Circuit Thermosiphon: Corrosion-resistant solar-powered water heating.
TRV Valve: Pressure relief valve for smooth operation.
Super Shield Enamel: Advanced corrosion protection for long-term durability.
Energy Efficient: Save up to 65% on water heating costs.#
Reduced CO₂ Emissions: Save up to 2.3 tonnes of CO₂ annually.#

Warranty:

10-year warranty on the collector and tank.*
5-year warranty on parts and labour.*

Collectors:

2 x SP Collectors - for efficient performance in medium to high solar gain areas.

Specifications

Thermosiphon SP Closed Circuit Systems
System Model	302SP
Tank Model	SP - 300J Free Heat - 300F
Storage Capacity (litres)	300
Boost Capacity (litres)	150
Weight Empty - Tank Only (kg)	107
Weight Full - Tank Only (kg)	407
A-Width* - Tank Only (m)	2.43
Weight Empty - System (kg )	210
Weight Full - System (kg)	529
A-Width* - System (m)	2.43

Collectors SPA2000
Aperture Area (m2)	1.8
Length (mm)	1996
Width (mm)	1043
Height (mm)	82
Capacity (litres)	3.8
Weight Empty (kg)	47
Weight Full (kg)	51
Working Pressure - No OTP (kPa )	80
Working Pressure - With OTP (kPa)	170
Absorber Surface SPA2000	Black polyester powder coat
Absorber/Riser Material	steel
Number of Risers	35
Frame Material	extruded aluminium
Insulation Material (Base)	38 mm glass wool blanket
Glass	3.2 mm tempered low iron

Water Supply
TPR Valve Setting (kPa)	1000
ECV* Setting (kPa)	850
Max Supply Pressure - With ECV (kPa)	680
Max Supply Pressure - Without ECV (kPa)	800
Water Connections - Cold	Rp 3/4
Water Connections - Hot	R 1/2

Electric Boost Specifications
Heating Unit Type	Copper sheath immersion element
Supply Voltage	220 V - 250 V

How it works

How Roof Top Solar Systems Work Solar Operation

The 302SP solar system has its vitreous enamel lined solar storage tank installed on the roof directly coupled to the solar collectors. In the Closed Circuit Series, heat is absorbed by the collector and passed to the ‘Hartgard’ heat transfer liquid inside the collector. As the temperature of the ‘Hartgard’ increases, the hot fluid rises up through the collector by the Natural Thermosiphon Principle, into the heat exchanger jacket around the potable water storage tank. Here, the heat is transferred to the potable water, cooling the ‘Hartgard’ fluid. The cooler fluid is then forced back down into the collectors through the displacement action of further hot fluid rising up into the heat exchanger jacket.

Orientation of Solar Collectors

To help maximise system performance, solar collectors should be installed with an optimum orientation facing true north (in the southern hemisphere) or true south (in the northern hemisphere). Always check for true north or true south using a compass or other suitable device.
To help maximise system performance, solar collectors should be installed with an optimum inclination. This is equal to 90% to 100% of the local latitude angle when collectors are oriented within 60° of true north or true south, and between 10° and 20° if the collectors are oriented between 60° and 90° from the optimum orientation. Generally, improved summer performance is obtained from an angle of inclination less than the optimum angle and improved winter performance is obtained by an angle of inclination greater than the optimum angle. If the angle of inclination varies by 20° from the optimum angle, the solar collectors will receive about 10% less total annual solar radiation.

Frost/Freeze Protection

Solahart Closed Circuit Systems are protected against freezing or harsh water conditions by our exclusive ‘Hartgard’ fluid. ‘Hartgard’ is a blue, non-toxic, propylene glycol fluid which, when mixed with water, provides the Heat Transfer Fluid contained in the solar collectors and the heat exchanger jacket around the tank. ‘Hartgard’ is used to lower the freezing temperature of the Heat Transfer Fluid and so provides protection against freezing (Note: for the correct % of Hartgard in the Heat Transfer Fluid, refer to the section on Frost / Freeze Protection). ‘Hartgard’ is a special food grade solution and is the only solution permitted to be used in the closed circuit systems. Hartgard has been approved by the National Health and Medical Research Council of Australia.

Solar Boosting

In-Tank Boosting
An isolating switch is installed in the electrical meter box for an electrically in-tank boosted model. This should be left switched on to allow the booster heating unit to operate if required. The booster heating unit is for heating the water at times of low solar energy gain, such as during very cloudy or rainy weather, or during the colder months. The booster heating unit will only activate if heating is required and power is available from the switchboard. When the water is below the thermostat setting, the booster heating unit will turn on and heat the water. The booster heating unit will automatically turn off when the temperature of the water reaches the thermostat setting. If the water temperature drops below the setting again the booster will re-activate.

In-Series Gas Boosting
An in-series gas booster (also known as an continuous flow gas booster) can be installed between the solar water heater and the hot outlets in the house. This booster should be permanently active. The booster senses the temperature of the water passing through it: if the water temperature is above its temperature setting it does nothing; if below it will automatically heat the water up to the preset outlet temperature setting. This booster ensures hot water delivery for a variety of hot water demands without the need for user intervention while enabling maximum solar energy contribution to the water heating. For more information on this booster, consult the owner’s manual for the product.

Over-Temperature Protection System

The Closed Circuit Series solar water heaters have a means of controlling the maximum temperature of the water in the storage tank. These systems may be installed with a ‘HartStat’ valve located between the hot outlet of the collectors and the inlet to the tank heat exchanger. This valve closes when the tank has reached a sufficiently high temperature, thereby preventing further heat transfer to the tank, and thus limiting its temperature.