Rheem Water Heater - Manual (Page 24)

INSTALLATION – SOLAR STORAGE TANK
24
RAIN WATER TANK
If the solar collectors and solar pipe work are to be 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. The installer should
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 section of roof and gutter should be isolated from the rainwater collection
system before the commissioning of the solar water heater, so that any leak or
spillage during commissioning does not make its way into the rainwater tank.
This section of roof and guttering can be isolated by either:
• blocking this section of gutter from the remaining gutter and fitting two
separate down pipes, one to take any run-off water from that section of roof
away to drain and the other to the rainwater collection side of the gutter to
take the rain water run off to the rain water tank.
• blocking this section of gutter from the remaining gutter and fitting a tube or
pipe of a material compatible with the gutter material in this section of the
gutter and penetrating the separation pieces at either end to allow rainwater
runoff to pass from one part of the rainwater collection system to the other.
It may be necessary to fit a down pipe to the section of blocked gutter to
take any run-off water from that section of roof away to drain.
• installing a false gutter inside of the existing gutter, with a down pipe
penetrating the existing gutter to take any run-off water from that section of
roof away to drain. The false gutter should be no deeper than half of the
depth of the existing gutter, so as to enable rain water run off to flow under
the false gutter.
• installing a flashing from the underside of the roofing material, with a
continuous fall, to over the outside lip of the gutter. The flashing should
extend wider than the collectors and pipe work and turned up at the ends so
if there is leakage of closed circuit fluid, it cannot enter the gutter.
If any of these solutions are not practical, then the installer should discuss
alternative options to suit the installation with the house holder.
Any alterations to the roof drainage system must comply with the relevant
building regulations, codes and standards.