STIEBEL ELTRON sol 20 si Bedienung Und Installation Seite 29

2.11 Filling the heat transfer medium
circuit
Observe the EC safety datasheet
!
for H - 30 L, and fit a copy
somewhere accessible at the system.
Wear protective gloves and goggles
when handling H - 30 L or H - 30 LS.
Never fill the system when it is subject
to strong insolation. This could lead to
steam hammer inside the collectors.
If the sun shines during commissioning,
cover the collectors or wait until there is
some shade. Never fill and pressure test
the system with water when there is a risk
of frost. Fill the system after the pipework
installation, after connecting the collectors
and filling the cylinder. Use a solar filling
facility for filling the system.
Alternative:
Q
A comparable power drill pump.
Flushing the system | Preparations:
Set the pressure vessel prior to filling the
system to a pre-charge pressure of 3.0 bar.
During all filling and draining procedures,
open the air vent valve at the highest point
of the system. Close the air vent valve again
as soon as liquid is expelled. Potable water
without solar medium is generally used for
the initial fill for pressure testing.
Never fill the system with water
!
when there is a risk of frost.
»
Close the flow meter adjusting screw at
the pump assembly (horizontal position).
Connect a hose to the open fill & drain
valve at the top and allow water to stream
downwards through the collectors down
to the open fill & drain valve at the
bottom.
»
Fill the system slowly and continue this
process, until clear water is expelled from
the open drain valve.
»
Drain the water off after flushing has
been completed.
Filling and venting the system
Fill the solar heating system exclusively
with H - 30 L or H - 30 LS heat transfer
medium. The bottles have been premixed
and require no further treatment.
Never admix water or alternative
!
heat transfer media, otherwise the
essential characteristics and corrosion
protection can no longer be guaranteed.
Therefore, never top the system up with
water.
Connect the hose to the filling pump:
Q
— From the pump (pressure side) to the
top fill & drain valve
— From the bottom fill & drain valve into
the solar medium container
— From the solar medium container to the
pump (inlet side)
— Start the fill pump and pump the solar
medium into the system
»
Flush the system until no more bubbles
are expelled from the drain hose.
»
For an easy removal of any air pockets or
buffers from the system, open the bottom
fill & drain valve during the flushing
process and let the fill pump build to a
system pressure of approx. 2 to 3 bar.
»
Then fully open the bottom fill & drain
valve.
»
During this process, firmly hold the drain
hose inside the container.
»
Repeat this process approx. three to five
times.
»
Close the bottom fill & drain valve after
completing this ventilation step and raise
the system pressure to 3.5 bar.
»
Then also close the top fill & drain valve.
»
Now open the air vent valve at the
highest point, until only solar medium is
expelled.
»
Raise the system pressure in a cold state
to its operating pressure of 3.5 bar
»
Let the solar heating system rest over
night and vent again in the morning via
the air vent valve before insolation affects
the collectors. Close the air vent valve
again.
»
Close both fill & drain valves with the caps
supplied.
If the system does not start automatically,
there may still be air in the system. Repeat
the venting process, if required.
The safety valve drain must
!
terminate in a container (in
accordance with DIN 4757 - check local
regulations) that can hold the entire
system contents. In case of smaller
systems, the empty heat transfer
medium can is adequate. Dispose of
spent heat transfer medium H-30 L by
permissible means.
2.12 Pressure test
After the pipework has been installed and
the collectors have been connected, carry
out a pressure test of the system.
Carry out the pressure test
!
exclusively with H - 30 L or H - 30 LS
heat transfer medium.
The test pressure is 7.8 bar (1.3 x the
permissible operating pressure to DIN 4757).
The pump is connected to the filling
connector of the SOKI. For this, remove the
safety valve and seal the connection.
Refit the safety valve correctly
!
after the pressure test has been
completed.
Only fit the thermal insulation after the leak
test has been successfully completed.
Leak test
Close the bottom fill & drain valve and raise
the system pressure up to 6 bar and let the
system stand a few hours. Check all fittings.
Drain the system fully.
In case there is a risk of frost, immediately
fill the system with solar medium.
2.13 Commissioning
Re t igh ten all f i t t ing s
commissioning.
The minimum filling pressure of a
!
cold system (below 30 °C) is 3.5 bar.
Complete the "Commissioning report" after
commissioning.
Set the integral control unit to manual to
check, whether all required relays of the
solar control unit are connected. For this,
observe the operating instructions of the
respective control unit. Then 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.
Q
Hose
Power drill
pump
Heat transfer
medium
p r io r t o
Power drill
29