Rittal SK Serie Notice De Montage page 9

10. Notes on discharge
of condensate
1
A drain hose must be fitted to the /
2
socket protruding from the unit, to discharge any
condensate water accumulating.
For SK 3219.100 / SK 3249. . . . connect drain
hoses with elbow sockets (do not kink!) and direct
immediately downwards to avoid reflux and over-
flow of the condensate into the inside of the unit.
Fig. 10.1 Condensate discharge
SK 3219.100 / SK 3249. . . .
In order to ensure the safe discharge of conden-
sate, the following points must be observed:
Discharge hose must be routed free from kinks!
Do not reduce the hose cross-section!
Always install the drainage hose with a
downward slope!
In order to prevent increased development of con-
densate and also in the interest of energy savings,
the cooling water temperature should be matched
to the required cooling output (see performance
diagrams).
11. Safety instructions
When installing the device, the condensate
discharge must be routed out of the enclosure!
In order to avoid frost damage, the minimum
permissible water temperature of +1°C must
not be undercut at any point in the water cycle!
It is essential to obtain the manufacturer's
permission before adding anti-freeze!
During storage and transportation below
freezing point, the water cycle should be
drained completely using compressed air!
Only set the thermostat as low as is strictly
necessary, because of undercutting the dew
point with a falling water inlet temperature
(condensation)!
It is very important that the enclosure is sealed
on all sides (IP 54), particularly the cable entry
(condensation)!
12. Notes on water quality
For safe operation of the above-mentioned equip-
ment, it is vital to observe the VGB Cooling Water
" flanged
Guidelines. (VGB-R 455 P).
Cooling water must not cause any boiler scale
deposits or loose precipitation; it should therefore
have a low hardness, in particular low carbonate
hardness. Particularly in the case of recooling
during operation, the carbonate hardness must
not be too high. On the other hand, the water
should not be so soft that it corrodes the materi-
als. In the case of recooling of the cooling water,
the salt content should not rise too high as a result
of dilution of large quantities of water since as the
"
1 concentration of dissolved substances rises, the
/
2
electrical conductivity rises, so the water be-
comes more corrosive. For this reason, not only
must a corresponding quantity of fresh water be
constantly added but also part of the concen-
trated water must be removed.
Pollution of the water
Mechanical impurities
Excessive hardness
Moderate content of mechanical impurities
and hardness formers
Moderate content of chemical impurities
Biological impurities myxobacteria and algae
In the interests of operation as designed of a
recooling unit, which is operated on at least one
side with water, the condition of the water used
Hydrological data
pH value
Carbonate hardness
Free carbon dioxide
Associated carbon dioxide
Aggressive carbon dioxide
Sulphides
Oxygen
Chloride ions
Sulphate ions
Nitrates and nitrites
COB
Ammonia
Iron
Manganese
Conductivity
Solid residue from evaporation
Potassium permanganate consumption
Suspended matter
1)
The complete absence of corrosion under test conditions suggests that the system is capable of
tolerating far more saline solutions with a higher corrosion potential (such as seawater).
13. Spares list
(see page 18)
Gypseous water is not suitable for cooling pur-
poses, as it tends to form boiler scale, which is
particularly difficult to remove. Cooling water
should also be free of iron and manganese, as
otherwise deposits occur which adhere to the
pipes and block them. Organic substances
should at the most be present in small quanti-
ties, as otherwise sludge deposits occur.
12.1 Preparation or care of the water in
recooling systems
Depending on the equipment to be cooled, cer-
tain requirements are laid down for the purity of
the cooling water. Depending on its impurity and
the size and construction of the recooling
systems, a suitable process is then used to pre-
pare and/or look after the water being used. The
main impurities and most usual procedures for
eliminating them in industrial cooling systems
are:
Process
Filtration of the water via
sieving filter
– sand filter
– cartridge filter
– precoated filter
Softening of the water by ion exchange
Injection of stabilisers or dispersants
into the water
Injection of passivators and/or inhibitors
into the water
Injection of biocides into the water
should not differ substantially from the following
list of hydrological data:
SK 3212.xxx / SK 3247.000 /
SK 3219.100 / SK 3249.100 /
SK 3218.104
SK 3214.100 / SK 3215.100 /
SK 3249.104
SK 3216.100 / SK 3217.100 /
SK 3218.100
7 – 8.5 6 – 9
> 3 < 8 °dH 1 – 12 °dH
3
8 – 15 mg/dm 1 – 100 mg/dm
3
8 – 15 mg/dm free
3
0 mg/dm 0 – 400 mg/dm
free free
3
< 10 mg/dm < 10 mg/dm
3
< 50 mg/dm < 200 mg/dm
3
< 250 mg/dm < 500 mg/dm
3
< 10 mg/dm < 100 mg/dm
3
< 7 mg/dm < 40 mg/dm
3
< 5 mg/dm < 20 mg/dm
3
< 0.2 mg/dm free
3
< 0.2 mg/dm free
< 2200 µS/cm < 4000 µS/cm
3
< 500 mg/dm < 2000 mg/dm
3
< 25 mg/dm < 40 mg/dm
3
< 3 mg/dm
3
> 3 < 15 mg/dm part flow cleaning recommended
3
> 15 mg/dm continuous cleaning recommended
1)
1)
3
3
3
3
3
3
3
3
3
3
5