Maintenance Work; Testing The Pressure Relief Valve; Descaling And Cleaning; Checking The Magnesium Anode - Buderus Logalux SM310.5 E Installation And Service Instructions Manual

9
Inspection and maintenance
9.4

Maintenance work

9.4.1

Testing the pressure relief valve

▶ Check the pressure relief valve annually.
9.4.2

Descaling and cleaning

In order to improve the cleaning effect, heat up the heat exchanger prior
to cleaning it with a water jet. The thermal shock effect separates
deposits (e.g. limescale) more readily.
▶ Isolate the cylinder from the piping on the domestic water side.
▶ Close the shut-off valves and isolate the immersion heater (if used)
from the mains power supply. ( Fig. 18, page 72).
▶ Drain the cylinder ( Fig. 17, page 72).
▶ Open the inspection aperture on the cylinder.
▶ Check the interior of the cylinder for pollution.
-or-
▶ In the case of soft water:
Check the container regularly and clean to remove limescale.
-or-
▶ In the case of hard water or severe pollution:
Regularly descale the cylinder in line with the actual amount of
limescale using chemical cleaning methods (e.g. with a suitable
descaling agent based on citric acid).
▶ Hose down the inside of the cylinder ( Fig. 21, page 73).
▶ Use a wet & dry vacuum cleaner with plastic suction hose to remove
the residues.
▶ Close the inspection aperture with a new gasket
( Fig. 22, page 73).
9.4.3

Checking the magnesium anode

Failure to service the magnesium anode properly voids the warranty for
the cylinder.
The magnesium anode is a sacrificial anode, which is consumed when
the cylinder is in operation. Two types of magnesium anode can be used.
• A non-insulated magnesium anode ( Variant A, Fig. 26, page 74).
• An insulated magnesium anode ( Variant B, Fig. 26, page 74).
9.6

Checklist for maintenance

▶ Fill out the report and note the tasks performed.
Date
1 Check the function of the
pressure-relief valve
2 Check tightness of
connections
3 Descale/clean
the inside of the cylinder
4 Signature
Stamp
Table 54 Checklist for inspection and maintenance
48
We recommend that insulated magnesium anodes are additionally
checked regarding the protection current using an anode tester on an
annual basis ( Fig. 24, page 74). The anode tester is available as an
accessory.
NOTICE
Corrosion damage!
If the anode is neglected, this could lead to premature corrosion.
▶ Inspect the anode every one or two years, depending on the on-site
water quality, replace if required.
Never bring the magnesium anode surface into contact with oil or grease.
▶ Keep everything clean.
▶ Shut off the cold water inlet.
▶ Depressurise the cylinder ( Fig. 16, page 72).
▶ Remove and test the magnesium anode
( Fig. 25 to Fig. 28, page 74).
▶ Replace the magnesium anode if its diameter has been reduced to
less than 15 mm.
▶ If the magnesium anode is insulated: check the transfer resistance
between the protective conductor connection and the magnesium
anode. If the anode current is <0.3 mA, replace the magnesium
anode ( Fig. 24, page 74).
9.4.4

Recommissioning

▶ Flush the cylinder thoroughly after cleaning or repair.
▶ Vent on the heating side and on the domestic water side.
9.5

Function check

NOTICE
Damage through positive pressure.
A pressure-relief valve malfunction can result in damage due to positive
pressure.
▶ Check the pressure-relief valve function and flush through several
times by venting.
▶ Never close the blow-off opening of the pressure-relief valve.
Logalux – 6721829955 (2020/12)