Lauda MC 250, Operating Instructions Manual, Page: 32 / 72

5 Commissioning
5.1 LAUDA heat transfer liquids
Note the following:
 The heat transfer liquids each cover a recommended tem-
perature range and must be suitable for the temperature range
of your application.
 At the lower limit of the temperature range, the heat transfer
liquid becomes more viscous and influences temperature con-
stancy, pump power and cooling capacity. The formation of
vapours and odours increases in the upper range. Therefore,
only use all of the temperature range if required. Particularly
with Aqua 90 (water), ice forms which can result in destruction
of the device.
 Never use contaminated or degenerated heat transfer liquids.
 You can request the safety data sheets of the heat transfer
liquid at any time if required.
Approved heat transfer liquids
LAUDA
designa-
tion
Chemical
designation
Tem-
perature
range in °C
Viscosity
(kin) in mm²/s
(at 20 °C)
Viscosity
(kin) in mm²/s
for
temperature
Container size
Catalogue number
5 l 10 l 20 l
Kryo 30
Mono eth-
ylene
glycol /
water
-30 ... 90 4 50 at -25 °C LZB 109 LZB 209 LZB 309
Aqua 90
decalcified
water
5 ... 90 1 --- LZB 120 LZB 220 LZB 320
Note the following for Kryo 30:
 The water content reduces during long operating with higher
temperatures and the mixture becomes flammable (flame point
128 °C). Check the mixture ratio using a hydrometer.
 The alkaline earth ions content (hardness) of the water must be
between 0.71 mmol/l and 1.42 mmol/l (equivalent to 4.0 and
8.0 °dH). Harder water results in lime deposits in the device.
 The pH value of the water must be between 6.0 and 8.5.
 Distilled, deionised, demineralised (DM) water or seawater
must not be used due to the corrosive properties. Ultra-pure
water and distillates are suitable as medium after addition of
0.1 g soda (Na
2
CO
3
, sodium carbonate) per litre of water.
 Any chlorine content in the water must be strictly avoided. Do
not add any chlorine to the water. Chlorine is contained, for
example, in cleaning agents and disinfectants.
Heat transfer liquid water
Commissioning
Microcool 32