INSTALLATION
–
SOLAR COLLECTORS
33
WARNING: Plumber – Be Aware
The solar hot and solar cold pipes between the solar storage tank and the solar collectors
MUST BE
of copper. All compression fittings must use brass or copper olives.
The full length of the solar hot and solar cold pipes
MUST BE
insulated.
The insulation must:
be of a closed cell type or equivalent, suitable for a solar water heating application and capable
of withstanding the temperature of the water generated by the solar collectors under stagnation
conditions
The specification of the chosen insulation material should be checked with the insulation
manufacturer prior to installation as different materials may vary in temperature tolerance.
be at least 13 mm thick, however thicker insulation may be required to comply with the
requirements of AS/NZS 3500.4
be weatherproof and UV resistant if exposed
extend through any penetrations in the eaves, ceiling and roof
cover valves and fittings in the solar hot and solar cold pipe work
be fitted up to and cover the connections on both the solar storage tank and the solar collectors.
Note: Failure to observe these requirements increases the risk of freeze damage.
Uninsulated pipe work, including concealed in cavities and roof spaces or where it may be in contact
with a metal roof, may lead to freeze damage. The system has NO WARRANTY for freeze damage
if the solar hot and solar cold pipes are not insulated in accordance with the installation instructions.
The insulation is essential to assist in providing freeze protection, will offer corrosion protection to a
metal roof against water runoff over the copper pipe, assist in avoiding accidental contact with the
solar pipe work as high temperature water can flow from the solar collectors to the solar storage tank
and also reduce pipe heat losses.
Plastic pipe
MUST NOT
be used, as it will not withstand the temperature and pressure of the water
generated by the solar collectors under stagnation conditions. The solar collectors can generate
extremely high water temperatures up to 150°C and high water pressure of 1000 kPa. Plastic pipe
cannot withstand these temperatures and pressures and
MUST NOT
be used. Failure of plastic pipe
can lead to the release of high temperature water and cause severe water damage and flooding.
The highest point of the solar cold pipe and solar hot pipe must be where they connect to the solar
collectors, to avoid the possibility of air locks occurring in the system. There
must be a continuous
fall
in the pipe work between the solar collectors and solar storage tank. Horizontal runs of pipe
work are acceptable and may be installed.
A non return valve
MUST BE
installed on the cold water line to the solar storage tank
AFTER
the
cold water branch to a temperature limiting device. Due to the higher water temperatures generated
under certain conditions in the solar collectors of this solar water heater, an additional effective back-
flow prevention device also should be used as an extra safeguard. Valve manufacturer RMC
recommends Dual Check Valve model N7150, as being suitable for this application.
The pressure applied to the solar circuit and solar collectors during a pressure test of a direct open
circuit system
MUST NOT
exceed 1000 kPa, otherwise damage may result to the solar collectors.
Refer to
“Pressure Testing”
on page 34.
