Rheem Water Heater - Manual (Page 7)

ABOUT YOUR WATER HEATER
7
PIPE WORK AND INSULATION
The solar hot and solar cold pipe work between the solar storage tank and the
solar collectors MUST BE of copper and fully insulated with closed cell polymer
insulation or similar (minimum thickness 13 mm). The insulation must be
weatherproof and UV resistant if exposed. 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 and also reduce pipe heat
losses.
The insulation must be fitted up to the connections on both the solar collectors
and the solar storage tank, as very high temperature closed circuit fluid can
flow from the solar collectors to the solar storage tank under certain conditions.
There must be a continuous fall in the pipe work from the solar collectors to the
solar storage tank. The continuous fall is essential to assist in the drain back
function of the solar system.
Plastic pipe MUST NOT be used, as it will not withstand the temperature of the
closed circuit fluid generated by the solar collectors under certain conditions
(refer to Warning on page 35 ) .
RAIN WATER TANK
If the solar collectors and solar pipe work are installed on a section of roof
which is part of a rain water runoff collection system, then it is recommended
this section of roof and its gutter be isolated from the rain water collection
system. The gutter should be isolated to a width greater than the solar
collectors and pipe work and must have suitable drainage. This is to ensure in
the event of a leak from the solar collectors or pipe work, a rainwater tank
cannot be contaminated with closed circuit fluid.
The closed circuit fluid contains food grade additives (rust inhibitor and anti-
freeze agent), is non-toxic and is harmless to the environment. However, if it
enters a rain water tank, it can kill off microscopic algae which are typically
present in the water causing an unpleasant odour to develop and resulting in
the rain water tank having to be drained and cleaned.
DOES THE WATER QUALITY AFFECT THE WATER HEATER?
The water heater is suitable for most public water supplies, however some
water qualities may have detrimental effects on the cylinder and fittings. If you
are in a known harsh water area
you must read page 76. If you are not sure,
have your water quality checked against the conditions described on page 76.