Rheem GAS BOOSTED SOLAR WATER HEATER - Manual (Page 28)

INSTALLATION – SOLAR COLLECTORS
28
WARNING: Plumber – Be Aware
• The solar hot and solar cold pipes 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. All
compression fittings must use brass or copper olives.
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.
• Plastic pipe MUST NOT be used, as it will not withstand the temperature of the closed circuit
fluid generated by the solar collectors under stagnation conditions. The solar collectors can
generate extremely high closed circuit fluid temperatures up to 150
°C. Plastic pipe cannot
withstand these temperatures and MUST NOT be used. Failure of plastic pipe can lead to the
release of high temperature closed circuit fluid and cause severe water damage and flooding.
• There must be a continuous fall in the pipe work between the solar collectors and solar
storage tank for efficient and effective drain back to occur. The highest point of the solar cold
pipe and solar hot pipe must be where they connect to the solar collectors.