Solahart 181SP
The Solahart 181SP provides a compact, high-performance solar water heating system, ideal for small households. Featuring closed-circuit thermosiphon technology, it ensures reliability and protection against corrosion in harsh water conditions.
Solahart 181SP Solar Water Heater: Key Attributes
Why the 181SP system is a smart choice
The Solahart 181SP is designed for smaller households of 1-2 people, providing a reliable solar hot water solution with a 180-Litre tank. It uses closed-circuit thermosiphon technology, offering enhanced protection against corrosion, especially in areas with harsh water conditions. The system includes a TRV valve for safe pressure relief and Super Shield Enamel® for added durability. With high efficiency and low maintenance, the SP Free Heat Series helps you reduce energy costs while providing eco-friendly hot water year-round.
Key Features:
- Capacity: 180-Litre tank, ideal for small households (1-2 people).
- Closed Circuit Thermosiphon: Efficient solar heating with corrosion protection.
- TRV Valve: Safe pressure relief during operation.
- Super Shield Enamel: Enhanced corrosion resistance for extended lifespan.
- 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:
- 1 x SP Collector - provides efficient performance in medium to high solar gain areas.
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Specifications
Tank Model - 180L Tank Storage Capacity (litres) 180 Boost Capacity (Electric) (litres) 90 Weight Empty (kilograms) 69 Weight Full (kilograms) 249 A-Width* (metre) 1.62 Tank Model - 181L System Storage Capacity (litres) 180 Boost Capacity (Electric) (litres) 90 Weight Empty (kg) 97 Weight Full (297) 297 A-Width* (m) 1.67 B-Length* (m) 2.53 L Collectors Aperture (heating) Area (m2) 1.87 Length (mm) 1943 Width (mm) 1027 Height (mm) 83 Capacity (litres) 1.2 Weight Emtpy (kg) 29 Weight Full (kg) 32 Working Pressure 1000 kPa
145 psiAbsorber Surface Black polyester powder coat Absorber Material aluminium Riser Material copper tube Tray Material 0.7 mm aluminium Insulation Material - Base 38 mm polyester blanket Glass 3.2 mm tempered low iron glass -
How it works
How Roof Top Solar Systems Work – Solar Operation
The 181SP 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 a 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 gas 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.
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