INSTALLATION
Commissioning
f To secure the sensor lead, press the plug into the cover
f
sleeve as far as it will go. In doing so, route the sensor lead
downwards out of the sensor well.
Note
If no temperature sensor is being used, seal the sensor
well by pressing the plug fully into the cover sleeve to act
as a dummy plug.
9.
Commissioning
Material losses
!
If a threaded immersion heater has been installed, the
maximum temperature of the cylinder may need to be
limited. This prevents the temperature limiters of the in-
stalled accessories from responding.
Material losses
!
A safety valve is required.
f Fill and vent the appliance.
f
f Fit and check accessories as required.
f
9.1
Oxygen diffusion
Material losses
!
Avoid open vented heating systems and underfloor
heating systems with plastic pipes that are permeable
to oxygen.
In underfloor heating systems with plastic pipes that are per-
meable to oxygen and in open vented heating systems, oxygen
diffusion may lead to corrosion on the steel components of the
heating system (e.g. on the indirect coil of the DHW cylinder, on
buffer cylinders, steel radiators or steel pipes).
Material losses
!
The products of corrosion (e.g. rusty sludge) can set-
tle in the heating system components, which may re-
sult in a lower output or fault shutdowns due to reduced
cross-sections.
Material losses
!
Avoid open vented solar thermal systems and plastic
pipes which are permeable to oxygen.
With plastic pipes that are permeable to oxygen, oxygen diffusion
can cause corrosion on the steel components of the solar thermal
system (e.g. on the indirect coil of the DHW cylinder).
18
| STH Plus
9.2
Water quality in solar circuit
A glycol/water mixture of up to 60 % is permitted for the indirect
coil in the solar circuit, provided only dezincification-resistant
metals, glycol-resistant gaskets and diaphragm expansion vessels
suitable for glycol are used throughout the system.
9.3
Appliance handover
f Explain the appliance function to users and familiarise them
f
with how it works.
f Make users aware of potential dangers, especially the risk of
f
scalding.
f Hand over these instructions.
f
10. Appliance shutdown
f Disconnect any electrical accessories from the mains power
f
supply at the fuse in the distribution board.
f Drain the appliance. See chapter "Maintenance / Draining the
f
appliance".
11. Maintenance
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with relevant regulations.
If you need to drain the appliance, observe chapter "Draining the
appliance".
11.1 Draining the appliance
WARNING Burns
Hot water may escape during draining.
If the appliance needs to be drained for maintenance or to protect
the whole installation from frost, proceed as follows:
f Close the shut-off valves in the inlet lines.
f
f Connect a drain line to the drain valve (not included in stand-
f
ard delivery).
f Open the drain valve.
f
f When the excess pressure has been released, open the air
f
vent valve (see chapter "Specification / Dimensions and con-
nections") and drain the appliance.
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