Buderus SF300.5, Installation And Maintenance Instructions Manual

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9 Servicing
SF300/5, SF400/5 – 6 720 800 028 (2012/05)
13
B
In the case of soft water:
Check the cylinder interior regularly and clean out any sediment
deposits.
-or-
B
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).
B
Clean out the DHW cylinder interior with a water jet
(
Æ
Fig. 20, page 50).
B
Remove the residues with a wet & dry vacuum cleaner with plastic
suction hose.
B
Close the inspection aperture with a new gasket
(
Æ
Fig. 21, page 50).
B
Re-commission the DHW cylinder (
Æ
chapter 6, page 11).
9.2.3 Checking the magnesium anode
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 (
Æ
Fig. 23, page 51). The anode tester is available as
an accessory.
B
Shut off the cold water inlet.
B
Depressurize the DHW cylinder (
Æ
Fig. 15, page 49).
B
If LAP is present:
–
Depressurize the heating-side of the system
–
Disconnect LAP on feed and return side
B
Install and test the magnesium anode (
Æ
Fig. 23 to Fig. 25,
page 51).
B
Replace the magnesium anode if its diameter has been reduced to
below 15 mm.
B
Check the transition resistance across the earth connection and the
magnesium anode.
The DHW warranty is void if the magnesium anode is not
correctly maintained.
Never bring the magnesium anode surface into contact
with oil or grease.
B
Keep everything clean.
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 8 Install magnesium anode ( Æ Fig. 26, page 51)