STIEBEL ELTRON SOL 27 PREMIUM W - Manual (Page 14)

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INSTALLATION INSTRUCTIONS
SOL 27 PREMIUM S & W COLLECTORS - 230016 & 230017
Collector Spacing
For latitudes up to 50°, use the following distances for
mounting solar arrays behind each other. For higher
latitudes, it may not be practical at all to orient solar arrays
behind each other because of the low sun angle.
At least 25 ft. (7.6 m)
Array spacing for 45° Vertical Mounting
on a flat roof or ground.
At least 14 ft. (4.0 m)
Array spacing for 45° Horizontal Mounting
on a flat roof or ground.
6 Commissioning the System
6.1 Pressure and Leak Test
After the pipe work has been installed and the collectors
have been connected it will be necessary to pressure-test
the system to detect leaks before fi lling the solar loop with
heat transfer fl uid. Propylene glycol solutions can leak
from much smaller gaps than can water; so such testing is
critical to assuring a successful installation. Recommended
test pressure is 80 psi. Thermal pipe insulation should
be installed only after the leak test has been successfully
completed.
It is recommended that compressed air be used to test the
system for leaks, as it is very easy to make repairs and it will
prevent loss of solar medium, spills, property damage, and
messy clean-up problems. Air is also capable of revealing
very small leaks, that water may not reveal, through which
propylene glycol will often leak. Leaks will be evident from
the sound of escaping air, observation of bubbles emanating
from fi ttings and other leak-prone components that are
coated with soapy water, and watching the pressure gauge
over time. Bear in mind that the pressure gauge will vary
some based on temperature of the air, so one must try to
read the pressure at nights when the system cools down to
ambient temperature or when covered.
6.2 Setting the Expansion Tank Pre-charge Pressure
While the leak testing is being performed, the installer
should set the expansion tank’s pre-charge pressure.
Make sure that the “wet” side of the expansion tank (pipe
connection) is vented to atmosphere. Using a compressor,
pre-charge the tank with air (or use pressurized nitrogen) to
a fi nal pressure of 5 psi less than the target system pressure.
For example, if the fi nal target system (solar loop) pressure
is to be 50 psig, fi ll the expansion tank to 45 psig (which is
the recommended default value). When complete, cap the
Schrader valve fi tting and re-attach the tank to the pump
station. Make sure the expansion tank always faces up (the
Schrader valve must be pointed down).
6.3 Final Charging & Venting
The solar heating system must be fi lled exclusively with the
premixed propylene glycol heat transfer medium. Stiebel
Eltron glycol containers have been premixed and require no
further treatment. Never mix water with the heat transfer
fl uid, otherwise the essential characteristics and corrosion
protection can no longer be guaranteed. The system must
not be topped off with water.
More Information
For more detailed instructions on how to fi ll, fl ush & charge
the solar loop, consult the pump station manual.
7 Maintenance & Care
Specialists should carry out an annual inspection of the
solar heating system to ensure proper functioning of the
system and its components, including the control unit, safety
equipment, and tank. System components (fi ttings, thermal
insulation, mounting hardware, fasteners, etc.) exposed