9
Maintenance
SM80/5, SM100/5 – 6 720 800 156 (2017/07)
16
▶ Loosen the hex bolts [5] in the cleanout cover [4].
▶ Remove the cleanout cover [4], magnesium anode [3] and cleanout
cover gasket [2].
Fig. 19 Removing the cleanout cover
[1]
Inspection port
[2]
Handhole cover gasket
[3]
Magnesium anode
[4]
Handhole cover
[5]
Hex bolts
[6]
Cleanout cover shroud
9.2
Descaling/cleaning the tank
▶ Check the DHW tank interior for scale deposits (calcium).
Should limescale be discovered inside the DHW tank, proceed as
follows:
▶ Hose down the inside of the DHW tank with a "high pressure"
(approx. 58 – 72.5 psi (4 – 5 bar) gauge pressure) stream of cold
water (
Fig. 20, page 16).
You can increase the cleaning effect by heating up the heat exchangers
in the drained DHW tank before cleaning. The thermal shock effect
releases scale deposits more easily from the coil-type heat exchanger.
▶ Use a wet & dry vacuum cleaner with plastic suction hose to remove
the residues.
Extremely tough limescale inside the DHW tank can be removed by
chemical means. We recommend that you have a qualified contractor
carry out the chemical cleaning operation.
Fig. 20 Hosing down the interior of the DHW tank
9.3
Check the magnesium anodes
The purpose of the magnesium anode is to protect the storage tank
against corrosion.
Every year, check whether the magnesium anode must be replaced. The
surface of the magnesium anode must be free of deposits.
If the rod surface appears pitted, bumpy, rusty, deposits have built up on
the surface, or if the rod is less than 5/8" (15 mm) in diameter, then it
must be replaced.
Certain installations may require more frequent replacement of the
magnesium anode rod:
• Recirculation connection
• Poor water quality
• Galvanic/electrolytic corrosion
• High flow rate
In the event of poor water quality it is recommended that a water
treatment professional be consulted for water treatment options. The
DHW cylinder warranty is void if the magnesium anode is not correctly
maintained.
Checking the top magnesium anode
▶ Remove PS top cover if not already removed.
▶ Unscrew the magnesium anodes.
▶ Check the magnesium anodes for degradation.
▶ Replace the magnesium anode if the diameter has decreased to
approx. 5/8" (15 mm).
NOTICE:
Risk of tank damage due to damaged enamel.
▶ Never use hard objects or tools with sharp edges to
clean the interior of the tank.
6720 800 155-02.1ITL
The warranty is void if the magnesium anode is not
correctly maintained. Annual service records must be
kept in a safe location and submitted together with the
original purchase receipt in the event of a warranty
claim.
Never bring the magnesium anode surface into contact
with oil or grease.
▶ Keep everything clean.
