© STULZ S.p.A. – all rights reserved IT/10.2021/i04
WLA CompACT - TRANSLATIoN oF oRIGINAL INSTRUCTIoNS
6.2.
Features of primary fluid
In this unit its possible to use tap water which respects the values reported in the table below.
We recommend the use of premixed fluid COSMOTEC No frost N25 / N39 or COSMOTEC No frost
L38. Alternatively its possible to use Clariant Antifrogen N or Clariant Antifrogen L, respecting the
concentrations recommended in the data sheet of the product.
INFoRmATIoN
Check the manual Part II° for any changes..
Using other mixtures could invalidate the chiller warranty..
Features
minimum value
maximum value
pH
(*)
7,0
8,0
Total hardness
(*)
°F
13
35
Conductivity
(*)
µS/cm
200
350
Alkalinity (HCO3)
(*)
mg/L
200
300
(*)
Considering water at tempe20°C
WARNING
For water coming out from the unit with temperature equal to or less than +5°C and in
environments where the temperature is below 0°C, using water/glycol mixtures
INFoRmATIoN
The mixture with glycol modifies the performance of the unit.
WARNING
The chiller cannot be used out of limits specified in the technical nameplate.
6.2.1 Glycol correction factors
INFoRmATIoN
In the case of addition of glycol in the fluid to be cooled, the technical data contained in this
paragraph shall be adjusted according to the coefficients shown in the following table.
Features
percentage of
ethylene glycol
percentage of
propylene glycol
20%
30%
30%
Freezing temperature
[°C]
-8,9
-15,6
-12,2
Cooling capacity
Correction
factors on the
technical data
sheets
0,990
0,984
0,974
Power absorbed
0,997
0,996
0,993
Flow of fluid to be cooled
1,033
1,068
1,017
Pressure drop on the fluid to be cooled side
1,16
1,30
1,23
27
