
INSTALLATION – SOLAR COLLECTORS
36
WARNING: Plumber
– Be Aware
The solar hot and solar cold pipe work between the thermosiphon solar storage tank and the solar
collectors are supplied in the pipe kit. The supplied copper solar hot and solar cold pipes
MUST BE
used.
If the solar water heater is installed either on a metal roof or in a trafficable area, such as on an
accessible roof, then the solar hot and solar cold pipes must be insulated. The solar hot and solar
cold pipes may be required to be insulated to comply with local regulations.
If insulation is required, 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 or closed circuit fluid 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
be fitted up to and cover the connections on both the solar storage tank and the solar collectors.
The insulation 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 or
closed circuit fluid 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 closed
circuit fluid (indirect system) and water (direct system) generated by the solar collectors under
stagnation conditions. The solar collectors can generate extremely high water or closed circuit fluid
temperatures up to 150°C and high water pressure of 850 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 closed circuit fluid and water and cause severe water damage and flooding.
There
must be a continuous fall of a minimum 10°
in the pipe work from the thermosiphon solar
storage tank to the solar collectors. The highest point of the solar cold pipe and solar hot pipe must
be where they connect to the thermosiphon solar storage tank, otherwise thermosiphoning will not
occur.
The solar water heater is to be isolated during the testing and commissioning of the heated water
reticulation system in a building, in accordance with Clause 11.1 and 11.3 (a) of AS/NZS 3500.4.