Heliocol HC10.5, Руководство по установке, Страница: 11 / 29

Plumbing
It is important that you use the proper size PVC pipe
for the size of the solar array. Using a pipe that is too
small will produce too much restriction to the water flow
and unnecessarily reduce the flow rate to the collectors.
Use the following as a guide:
For larger flow rates, consult your Heliocol representa-
tive for the proper pipe size or alternative series plumb-
ing techniques which will reduce the necessary flow
rates on larger systems.
Plumbing runs should be as short as possible and the
“hot return” pipe should have the shortest run to reduce
potential heat loss in this pipe. Pipes should be sup-
ported with pipe clamps or “G” pipe clamps at least
every four feet to prevent sagging. (Check the plumbing
code in the local jurisdiction.) The pipe clamp used on
pipe returns across a roof should be ½’ larger than the
pipe diameter to allow for expansion and contraction.
The pipe clamp used on vertical roof piping or piping
running up the sides of the building should be the same
size as the pipe diameter to prevent vibration and to
assure a professional-looking installation.
Since 90 degree elbow fittings produce a high restric-
tion to flow, you will want to use a few as possible. Keep
this in mind when planning your plumbing runs. Their
use cannot be avoided, but with careful forethought,
you will use the least number possible. Occasionally,
the use of two 45 degree fittings will eliminate a 90, but
it is not necessary to always use them as this will run
up the expense of your materials.
Balanced Flow
When you have to split a solar system (Fig. 4.2 or Fig.
4.3, pg. 7) it is critical that the shown plumbing runs be
followed to assure equal water flow through both rows
of collectors. Since water will follow the path of least re-
sistance, if one plumbing run is shorter than the other,
more water will flow through it than through longer one.
Keep this in mind if you design a collector layout differ-
ent than the examples. Your Heliocol representative can
also assist with this and explain the use of “balancing
valves” on larger systems.
If you are installing the solar collectors on a flat roof or
flat ground rack, the top (return) header of the collec-
tor should be a least 3” higher than the bottom (feed)
header to assure equal flow through all of the tubes of
all of the collectors. (See pg. 13) To achieve even distri-
bution of water throughout the row of collectors, proper
flow rates and a little back pressure should be present.
Automatic Drain Down
The collectors and the PVC pipe should be installed
so the water will drain out of them when the pool pump
shuts off. This is especially important in areas of the
country where freezing conditions occur.
(The Heliocol
solar pool collectors are warranted against internal
freezing when installed to allow for drain down.)
To
allow for the water to drain a vacuum breaker, 121 is
installed on the solar feed line above the non-positive
3-way valve as shown on page 18, Fig. 15. (Non-positive
means that the valve allows for water to drain back
through the valve even when in the off position. If you
have a 3-way valve that is not non-positive, you can
make it so by drilling a 1/8” hole in the diverter.) If, as
a result of a unique roof design or adverse pool equip-
ment location, it is not possible to achieve complete
automatic drain down, manual drain down valves should
be installed in appropriate places in the plumbing or at
the end of the bottom (feed) header. Instead of installing
an end cap 106A at the end of the header, you would
place a pipe connector 117, a 1 ½” slip x 1/2” threaded
PVC reducer bushing along with a ½” boiler drain 140.
These valves should be opened when shutting down the
system for the winter months or when freezing condi-
tions are possible. On flat roof installations, it might be
necessary to open the collector connections at the end
of the swimming season and manually lift the collectors
to evacuate all the fluid from the system. Your Heliocol
representative can assist you with the parts necessary
for manual drain down installations.
Flow Rate
0 to 45 GPM
46 to 80 GPM
Recommended Pipe Size
1 ½”
2”
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