oventrop Regudis W, Installation Passport

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8 Decalcification of the heat
exchanger
8.1 Indications of a calcification of the heat
exchanger
• The set hot water temperature is only achieved
with low draw off capacities. The temperature
drops below the set value with high draw off
capacities.
• The draw off capacity drops.
• The return temperature increases.
8.2 Decalcification of the heat exchanger
Depending on the model of the station, the heat
exchanger can be flushed with a cleaning agent.
Alternatively, the heat exchanger can be replaced.
Clean the heat exchanger at an early stage. The
flow channels must not be blocked completely by
the chalk-bed!
1. For safety reasons, disconnect the power plug
from the socket before starting work on the
dwelling station in order to disconnect the
dwelling station from the power supply.
2. If the heat exchanger is removed for decalcifi-
cation, mark the connections, remove the heat
exchanger by loosening the four collar nuts and
place it on a level surface.
3. Clean the heat exchanger with a DVGW appro-
ved cleaning agent based on citric acid for
instance. The DVGW work sheets W 291 and
319 must be observed!
4. Apply the anti-liming liquid according to the
instructions of the manufacturer. If not specified
otherwise, it is recommended to leave the
anti-liming agent overnight. Repeat procedure
if necessary.
5. After decalcification, carefully drain off and
neutralise the heat exchanger and flush it
thoroughly with potable water. If necessary, flush
against the direction of flow! The safety and
cleaning instructions of the manufacturer must
be observed.
6. Neutralise and dispose the anti-lime liquid
according to the instructions of the manufacturer.
7. Connect the heat exchanger to the dwelling
station with new seals. The correct installation
position of the heat exchanger must be
observed.
8. Fill and bleed the dwelling station on the
primary and secondary side according to the
instructions.
9. Check the station for leaks and the electrical
components for firm seating and integrity.
10. Insert the power plug into the socket.
11. Compare the temperatures and flow values
with the default values during a functional test.
12. Compare the temperature setting of the
temperature controller with the hot water
temperature at the draw off point.
Risk of poisoning and acid burns!
Only use DVGW approved cleaning and anti-liming
agents which are suitable for the cleaning of a heat
exchanger.
Take care when handling chemicals!
The safety and processing instructions which are
enclosed with the cleaning agents must be obser-
ved.
Neutralise and dispose used chemicals according
to the instructions of the manufacturer.
The edges of the heat exchanger can lead to
injuries.
DANGER
!
Cleaning agents can lead to corrosion in the heat
exchanger. The instructions of the manufacturer
must be observed!
NOTE
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