Removing Casing Components Separately; Cleaning The Evaporator; Water Treatment; Descaling The Appliance - STIEBEL ELTRON WWS 20 Bedienung Und Installation

INSTALLATION
Maintenance and cleaning
f Undo the four fixing screws on the casing ring. f
f Hold the control fascia and pull the casing forwards slightly f
so that you can push it over the controller.
f Push the casing upwards. f
f Lift the casing upwards. f
f Refit the casing after completing your work. f

13.2 Removing casing components separately

If you do not have enough space to remove the entire casing from
the top, you can remove the appliance cover and casing ring sep-
arately.
Appliance cover removal
f Turn the appliance cover anti-clockwise. f
f Lift the appliance cover upwards. f
f Refit the appliance cover after completing your work. f
Note
When fitting the appliance cover, make sure that the air
intake and discharge apertures are positioned correctly.
Removing the casing ring
f Split the casing ring by moving the individual components f
together along the joint.
f Remove the casing ring. f
f Refit the casing ring after completing the work. f
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13.3 Cleaning the evaporator

WARNING Injury
!
The evaporator consists of numerous sharp-edged fins.
Take care when cleaning the evaporator. Wear protective
clothing, especially protective gloves.
To maintain a consistently high appliance output, check the evap-
orator of the appliance regularly for contamination, and clean as
necessary.
f Remove the appliance casing (see chapter "Removing the f
casing").
f Carefully clean the evaporator fins. Only use water and a soft f
brush for this. Never use acidic or alkaline cleaning agents.

13.4 Water treatment

Depending on water temperature and hardness, according to DIN
1988-7: 2004-12, the following water treatments should be carried
out:
dH [°] DHW temperature < 60 °C
0-14 None
14-21 Periodic descaling necessary (see
chapter "Descaling the appliance")
>21 Softening
Where water quality fluctuates significantly and the DHW temper-
atures are high (> 60 °C), we recommend annual inspection by a
qualified contractor.

13.5 Descaling the appliance

Material losses
!
Always use standard cleaning agents approved for use
with DHW cylinders to descale the appliance.
To descale the appliance, proceed as follows:
f Reduce pressure in the DHW cylinder by drawing off water. f
f Isolate the DHW cylinder from the heating system. f
f Connect a flush tap to the appliance. f
f Descale the primary pump and plate heat exchanger. f
f Reconnect the heating system to the DHW cylinder. f
f Refill the DHW cylinder (see chapter "Commissioning / Filling f
the DHW cylinder").
DHW temperature > 60 °C
Periodic descaling necessary (see
chapter "Descaling the appliance")
Softening
Use is not recommended
Reduce the DHW temperature
WWS 20 | 57