®
15
Horizontal runs of PVC pipe must be supported every
four
feet and all vertical runs of PVC pipe must be sup-
ported every
ten
feet. Vertical lines take the water from
the ground up to the roof and are usually on the walls
of the main structure. Pipe supports on the roof should
be sealed according to an industry standard method.
Pipe supports should be secured and properly guide
thermal movement (see figures in
Appendix C
).
Proper
plumbing installation enables the plumbing to move
minimally but accommodates movement of solar collec-
tor banks.
Both
Floating Guide
and
Fixed Guide
connections
should be incorporated in conjunction with an indus-
try standard method to absorb plumbing movement as
referenced in
Figure
20
of
Appendix C
.
Prime consideration should be given to system drain-
age and appearance when running pipe from the pool
pump to the collectors and back. Best practice allows
system drainage with a slight and consistent down-
ward slope in all horizontal runs.
Supporting PVC Pipe
Roof plumbing should schedule 40 PVC conforming
to ASTM D1785 or equivalent standard.
PVC is generally an acceptable material for plumbing
FAFCO
®
solar thermal systems. In most cases, an oper-
ating solar thermal system does not exceed the temper-
ature rating of white PVC. Unless it can be shown that
black PVC withstands equivalent temperature and pres-
sure specifications of white PVC by providing documen-
tation that it conforms to ASTM D1785 or an equivalent
standard, it should not be used for solar plumbing.
Due to the poor UV resistant properties of PVC, it
should be painted upon completion of the installation.
Plumbing Materials
PHASE I
—
Site Preparations & Planning Cont’d
Hybrid System Layouts
SunSaver
®
collectors are compatible with most sys-
tems, including FAFCO
®
’s CoolPV
®
panels.
The best way to install a hybrid SunSaver
®
/CoolPV
®
system is to prioritize placement and plumbing to the
CoolPV
®
panels and then to install SunSaver
®
collec-
tors on the remaining roof space. SunSaver
®
collec-
tors are less sensitive to location, which will have a
lesser impact on performance than a CoolPV
®
panel.
To see how a split Hybrid system should be plumbed,
refer to
Figure 8
.
Roof Penetrations
All mounting penetrations must be installed as de-
scribed in
Phase I Site Preparation and Planning.
All roof penetrations should be sealed with an in-
dustry standard method.
In many jurisdictions, painting the plumbing is re-
quired by code.
Instances occur where a system will be pressurized
while at elevated temperatures. CPVC offers a much
higher operating temperature and should be con-
sidered for use on the supply and return lines, es-
pecially for installations of more than two stories
and those likely to see water temperatures above
140
°
F such as sections of plumbing where water
can be entrapped at an elevated temperature. (see
Table 4,
Appendix C
).
Figure 8| Hybrid CoolPV
®
and SunSaver
®
Plumbing Schematic
