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Climate control equipment

Technical data

Cautions for coolant water and its quality criteria

Be sure to keep the quality standard shown below for the coolant water supplied to this product. In case well water or ground water is used, conform to the standard value for "Chilled water system circulation water or transient water" in the table. Do not use spa water.

Low-quality water may scale inside radiator pipe, leading deterioration of heat exchange efficiency. Also, it may corrode copper pipes, leading water leakage.
(Any trouble arisen from low quality water is not covered by warranty)

Water quality standard by Japan Refrigeration and Air Conditioning Industry Association Standard (JRA-GL02:1994)

Item Standard value Property
Circulation water with cooling tower *1 Chilled water system circulation water *2 or tramsient water *3 Corrossion Scale forming
1 pH (25℃) 6.5-8.2 6.8-8.0
2 Electric conductivity (mS/m) (25℃) 80 or less 40 or less
3 Chlorine iion (mgCl-/L ) 200 or less 50 or less
4 Sulfate ion (mgSO42-/L ) 200 or less 50 or less
5 Acid consumption (pH4.8)(mgCaCO3/L ) 100 or less 50 or less
6 Total hardness (mgCaCO3/L) 200 or less 70 or less
7 Calcium hardness (mgCaCO3/L ) 150 or less 50 or less
8 Ionic silica (mgSiO2/L ) 50 or less 30 or less
9 Iron (mgFe/L) 1.0 or less 1.0 or less
10 Copper (mgCu/L ) 0.3 or less 1.0 or less
11 Sulfide ion (mgS2-/L) Undetectable Undetectable
12 Ammonium ion (mgNH4+/L) 1.0 or less 1.0 or less
13 Chlorine residual (mgCl/L ) 0.3 or less 0.3 or less
14 Free carbon dioxide (mgCO2/L ) 4.0 or less 4.0 or less
15 Stability index (R.S.I.) 6.0-7.0 -
The mark ”✓” in the the table indicates that the item is a possible factor to generate corrosion or scale forming.
In case the water quality is outside the standard, we recommend improvement by chemical injection or other proper means. Please consult us for the details.

*1 Coolant water used for a system in which warmed water flown from heat exchanger is sprinkled by an atmosphere-open cooling tower to be cooled and recirculated
*2 Coolant water used for a closed loop circulation at a temperature less than 20℃
*3 Coolant water for a system in which all the water once passed through the heat exchanger is discharged