Fonderie Sime SpA reserves the right to amend all of the product and relative accessories specifications without prior warning.
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This manual provides all the necessary instructions for installing, operating and servicing the natural circulation sys-
tem SIME NATURAL 160S - 200S - 300/5.2S - 320S.
Nowadays we know that we need to produce and save energy without polluting the environment. Our planet's conven-
tional energy resources have decreased to an alarming level while people's energy requirements increase, generating
polluting agents that affect the climatic balance.
The renewable energy sources solve the energy and pollution problems. The international legislation is gradually modify-
ing and encouraging, even imposing, the use of alternative energy products with the aim of meeting the energy require-
ment without placing the environment at risk.
D.H.W. REQUIREMENT
It was statistically calculated that the average daily consumption of a family varies from 35-50 litres per person. Should
we add the consumption of the washing machine and dishwasher in case they were connected to the solar system, around
20 litres are required daily for each appliance (for one wash).
A family made up of four people with an average D.H.W. consumption of 40 litres per person, requires a 160 litre solar
water heater. The requirement increases by at least 40 litres per day if we add the domestic appliances connected to the
solar system. To obtain the maximum benefit from the solar water heater, use the highest amount of hot water possible
during the day so that the plant can continuously produce during the sunny period, maintaining yield to a maximum.
SOLAR SYSTEM FUNCTIONING - WATER HEATING
The collector surface heats the liquid (water or anti-freeze solution) circulating in the solar collector, through the so-
lar energy it absorbs. The heated liquid becomes less heavy and moves towards the boiler heating the water contained
therein. The collectors' liquid circulates naturally (thermosyphon flow).
There are many factors affecting the temperature of the water supplied by a solar panel and their oscillation values vary
depending on the season, time of day and place.
As the solar panel is a system exposed to atmospheric conditions, the essential parameters affecting its yield are the
supply water temperature, the solar energy available and the environment temperature.
The temperature of the mains water is not constant during the year as it is much colder in the winter than the summer.
Considering 45°C as satisfying D.H.W. temperature (to meet the requirements of a home), it is given from the static data
that the temperature of the mains water must increase by 35°C during the winter and 20°C in the summer.
Furthermore, the available solar energy is not constant during the year as it assumes lower values during the winter
months with respect to the summer period. The solar panel assures pre-heating and is assisted by using the electric
heater or the central heating boiler (triple energy systems), in cases of reduced sun and low environment temperature.
The heat losses during the night are minimised by the system's efficient thermal isolation. The leaks depend on the en-
vironment temperature that varies depending on the place and climatic conditions.
