Completing The Filling Procedure; Thermal Insulation; Commissioning; Maintenance - Stiebel Eltron SOL 27 BASIC Utilisation Et Installation

10.14 Completing the filling procedure
f Reduce the system pressure to the required filling pressure.
The minimum filling pressure of a cold system is 0.35 MPa
(3.5 bar).
f Close both fill & drain valves with the caps supplied.
f Attach the heat transfer medium safety datasheet to the
system.
f Allow the solar thermal system to rest overnight.
f Before the onset of strong sunlight, vent the system once
more the following morning using the air vent valve.
f Enable the gravity brake by turning the fill & drain valve to a
vertical position.
Note
During normal operation, the shut-off valves upstream
of the air vent valves in close proximity to the collector
must always be kept closed.
Damage to the appliance and the environment
The safety valve drain must terminate in a container that
can hold the entire system contents. In case of smaller
systems, the empty heat transfer medium can is ade-
quate. Dispose of spent process medium by permissible
means.

10.15 Thermal insulation

Ensure that the system undergoes a pressure test and a leak test
before applying thermal insulation.
Insulate all pipes. The insulation material is to be provided on site.
to 20 20
20 - 35 30
40 - 100 identical DN
above 100 100
For insulation material with a different thermal conductivity,
re-calculate the thickness of the insulation layer.
Use temperature and UV-resistant insulation material to provide
thermal insulation for the external pipes: Mineral wool which is
backed by aluminium mesh foil, a flexible EPDM hose or a clo-
sed-pore EPDM hose.
It is advisable to use a fixed armour made of aluminium sheet
around the mineral wool. The EPDM hose can be finished with
UV-resistant paint.
f Provide the collector sensor well and the roof outlet with
thermal insulation, which must be tightly sealed and must be
temperature and UV-resistant.
f If necessary, cut into the side of the insulation material and
seal the slit with adhesive tape after installation.
f Where required, protect the thermal insulation against bird
or rodent attack.

11. Commissioning

f Retighten all fittings.
f Check the system's filling pressure.
Note
The minimum filling pressure of a cold system (below
30 °C) is 0.35 MPa (3.5 bar).
f Check the pre-charge pressure of the expansion vessel.
Note
The expansion vessel must have a pre-charge pressure
of 0.3 MPa (3 bar).
f Complete the "Commissioning report".
f Set the integral control unit to manual. Please observe the
operating and installation instructions of the control unit
which is fitted into the system.
f Check whether all required relays of the solar control unit are
connected.
f Set the control unit back to automatic mode.
The system should then start automatically subject to all starting
conditions being met. If this is not the case, check in chapter
"What to do if ..." for a possible cause for this fault.

12. Maintenance

Note
We offer you the opportunity to take out a maintenance
contract.
12.1 Maintenance
f Check that the system, including the control unit, safety
equipment and cylinder, is functioning correctly.
f Check the parts of the system exposed to the weather, moun-
ting fixtures and thermal insulation to ensure that they are in
acceptable condition.
f Remove contaminants.
f Check the pH value (> 7) and frost protection level (-- 30 °C)
of the heat transfer medium. If necessary, replace the heat
transfer medium or top it up via the filler inlet in the solar
module.
CAUTION Injury
!
If the heat transfer medium needs to be drained to carry
out maintenance or repair work, this work must be car-
ried out by a qualified contractor.
Damage to the appliance and the environment
Before you remove the heat transfer medium from the
collector, the collector must be protected from daylight.
Cover the collector with an opaque material.