Tabla de contenido
Publicidad
Idiomas disponibles
Idiomas disponibles
9
Servicing
▶ Let the DHW cylinder cool down sufficiently prior to any maintenance
work.
▶ Carry out cleaning and maintenance procedures in the specified
intervals.
▶ Remedy all faults immediately.
▶ Use original spare parts only!
9.1
Maintenance intervals
Service the appliance in accordance with throughput, operating
temperature and water hardness ( Tab. 8).
The use of chlorinated DHW or a water softener unit reduce the service
intervals.
Water hardness in °dH
Calcium carbonate concentration in
mol/ m³
Temperatures
At a standard throughput (< cylinder content/24 h)
< 60 °C
60 – 70 °C
> 70 °C
At a higher throughput (> cylinder content/24 h)
< 60 °C
60 – 70 °C
> 70 °C
Table 8 Service intervals in months
You can check the local water quality with your water supply utility.
Depending on the composition of the water, it can make sense to deviate
from the reference values listed.
9.2
Maintenance work
9.2.1
Checking the safety valve
▶ Check the safety valve annually.
9.2.2
Descaling/cleaning the DHW cylinder
In order to improve the cleaning effect, heat up the
external heat exchanger prior to cleaning it with a water
jet. The thermal shock effect separates deposits (e.g.
lime scale build-up) more readily.
▶ Disconnect the DHW cylinder on the DHW side from the pipework.
▶ Close the shut-off valves and isolate the immersion heater from the
power supply (if installed) ( Fig. 14, page 48).
▶ Drain the DHW cylinder ( Fig. 15, page 48).
▶ Open the inspection aperture ( Fig. 18, page 49).
▶ Check the DHW cylinder interior for contamination (lime scale
deposits, sediment).
▶ In the case of soft water:
Check the cylinder interior regularly and clean out any sediment
deposits.
-or-
▶ In the case of hard water or severe contamination:
Regularly descale the DHW cylinder in line with the actual amount of
limescale using chemical cleaning methods (e.g. with a suitable
descaling agent based on citric acid).
▶ Clean out the DHW cylinder interior with a water jet
( Fig. 19, page 49).
▶ Remove the residues with a wet & dry vacuum cleaner with plastic
suction hose.
SF300.5 | SF400.5 – 6720819340 (2020/10)
3 – 8.4
8.5 – 14
> 14
0.6 – 1.5
1.6 – 2.5
> 2.5
Months
24
21
15
21
18
12
15
12
6
21
18
12
18
15
9
12
9
6
▶ Close the inspection aperture with a new gasket
( Fig. 20, page 50).
▶ Re-commission the DHW cylinder ( chapter 6, page 18).
9.2.3
Checking the magnesium anode
The DHW warranty is void if the magnesium anode is not
correctly maintained.
The magnesium anode is a sacrificial anode, which is consumed as the
solar storage tank is used.
We recommend that the protection current is measured annually using
an anode tester ( Fig. 22, page 50). The anode tester is available as
an accessory.
Never bring the magnesium anode surface into contact
with oil or grease.
▶ Keep everything clean.
▶ Shut off the cold water inlet.
▶ Depressurize the DHW cylinder ( Fig. 14, page 48).
▶ If LAP is present:
– Depressurize the heating-side of the system
– Disconnect LAP on feed and return side
▶ Install and test the magnesium anode ( Fig. 23 to Fig. 24,
page 50).
▶ Replace the magnesium anode if its diameter has been reduced to
below 15 mm.
▶ Check the transition resistance across the earth connection and the
magnesium anode.
Pos.
Description
1
Magnesium anode
2
Seal
3
Feed-through part
4
Washer
5
Serrated washer
6
Cable lug with earth cable
7
Handhole cover
Table 9 Install magnesium anode (
Servicing
Fig. 25, page 51)
9
19
Publicidad
Capítulos
Tabla de contenido
