Lauda Viscotemp 15 G, Operation Manual

Page: 35 / 132

09/2021
ECO Gold 35 / 134
6.4 Heat transfer liquids, cooling water and hoses
Note:
-
Tap water is unsuitable for operation with the thermostat due to the calcium carbonate content. The bath vessel may
calcify.
-
High purity water (from ion exchangers) and distilled or bidistilled water are unsuitable for operation due to the cor-
rosive properties of these media. High purity water and distillates are suitable as a medium after the addition of 0.1 g
of soda (Na2CO3, sodium carbonate) per liter of water.
-
Water containing iron (rust formation), chlorine (pitting) and untreated river water ("algae formation") is unsuitable.
-
The bath vessels of the LAUDA ECO thermostats are produced in stainless steel 1.4301 and are accordingly re-
sistant to mechanical and chemical stresses.
-
Metals have different electrochemical potentials. Therefore, in the case of direct contact between the tank and a
frame (copper for example) electrochemical oxidation may occur. The bath corrodes despite the use of high quality
materials on the tank. Avoid the use of this type of frame or direct contact with it or contact with non-ferrous metal
samples and the inside of the container. Use original LAUDA stainless steel frames or commercially available frames
in temperature-resistant plastics.
a)
Approved heat transfer liquids
LAUDA
designation
Operating
temperature
range
Chemical
characterization
Viscosity
(kin)
Viscosity
(kin) at
temperature
Flash
point Container size
Catalogue number
°C
mm²/s at
20 °C
mm²/s °C 5 L 10 L 20 L
Kryo 51 -50 – 120 Silicone oil 5 34 at -50 °C 120 LZB 121 LZB 221 LZB 321
Kryo 30 -30 – 90
Monoethylene
glycol/water mixture
4 50 at -25 °C -- LZB 109 LZB 209 LZB 309
Kryo 20 -20 – 170 Silicone oil 11 28 at -20 °C 170 LZB 116 LZB 216 LZB 316
Therm 160

60 – 160 Polyalkylene glycol 141 5 à 140 °C 260 LZB 106 LZB 206 LZB 306
Therm 180 0 – 180 Silicone oil 23 36 at 0 °C 250 LZB 114 LZB 214 LZB 314
Therm 250 50 – 250 Silicone oil 125 45 at 50 °C 300 LZB 122 LZB 222 LZB 322
Aqua 90

5 – 90 Decalcified water 1 -- -- LZB 120 LZB 220 LZB 320

At higher temperatures vaporization losses occur. In this case use a bath cover (

9). Use distilled water or pure de-
mineralized water only after adding 0.1 g of soda (Na
2
CO
3
sodium carbonate) per liter of water. Otherwise there is
the risk of corrosion!

The proportion of water reduces with longer working at high temperatures and the mixture becomes flammable (flash
point 119 °C). Check the mixing ratio using a hydrometer.

Not suitable for polycarbonate baths.
Silicone hoses are not suitable for silicone oils!
EPDM hoses are not suitable for mineral oils!