Toshiba RUAGP Series, Original Owner'S Manual

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A brazing plate water heat exchanger is built in a way that does not allow dismantling and cleaning or
component replacement.
Care must be exercised concerning the quality of the water used in a water heat exchanger in order to
prevent corrosion and scaling.
The minimum requirements for the quality of water used in a plate water heat exchanger are those
stipulated by the "Water Quality Guidelines for Cooling and Air Conditioning Devices"
(JRA-GL-02-1994) of The Japan Refrigeration and Air Conditioning Industry Association.
When using a rust inhibitor, scale inhibitor, or any other type of agent, make sure that it is a type that will
not corrode cast iron, stainless steel, copper, bronze, rubber and gasket.
Water quality standard values of chilled (warm) water and supplementary water
Note (1) Item names, term definitions, and units are in accordance with JIS K 0101. Units and values in brackets ({ }) are conventional
units provided for reference.
(2) A circle ( ○ ) in a cell indicates a factor related to corrosion or scaling.
(3) High temperatures (40°C or higher) generally result in a striking increase in corrosion. In the case of ferrous metal materials
in particular, if such material will come into direct contact with the water it is best to perform effective corrosion protection
measures, such as the addition of an anti-corrosion agents, deterioration, etc.
(4) Cooling water systems that uses a sealed cooling tower, closed-circuit circulation water and other supplementary water
depend on warm water system water quality standards, while sprinkler water and other supplementary water depend on
circulative water system water quality standards.
(5) Supply and supplementary source water means tap water (water supply), industrial water, or ground water. Purified water,
grey water, and softened water are not included.
(6) The above 15 items show representative factors of corrosion and scale impairment.
※ For details, refer to the "Water Quality Guidelines for Cooling and Air Conditioning Devices" (JRA-GL-02-1994) of The Japan
Refrigeration and Air Conditioning Industry Association.
Once-
through
Circulation Circulation water Circulation water
pH (25ºC ） 6.5 to 8.2 6.0 to 8.0 6.8 to 8.0 6.8 to 8.0 6.8 to 8.0 7.0 to 8.0 7.0 to 8.0 7.0 to 8.0 7.0 to 8.0 ○ ○
Electrical conductivity
(mS/m)(25°C
） 80 or less 30 or less 40 or less 40 or less 30 or less 30 or less 30 or less 30 or less 30 or less ○ ○
{ μ S/cm} (25°C
）
(1)
{800 or less} {300 or less} {400 or less} {400 or less} {300 or less} {300 or less} {300 or less} {300 or less} {300 or less}
Chloride ion (mgCl
-
/l) 200 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less 30 or less 30 or less
○
Sulphate ion (mgSO
4
2-
/l) 200 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less 30 or less 30 or less
○
Acid consumption (pH4.8)
(mgCaCO
3
/l) 100 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less
○
Total hardness (mgCaCO
3
/l) 200 or less 70 or less 70 or less 70 or less 70 or less 70 or less 70 or less 70 or less 70 or less
○
Calcium hardness
(mgCaCO
3
/l) 150 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less 50 or less
○
Ionic silica (mgSiO
2
/l) 50 or less 30 or less 30 or less 30 or less 30 or less 30 or less 30 or less 30 or less 30 or less
○
Iron (mgFe/l) 1.0 or less 0.3 or less 1.0 or less 1.0 or less 0.3 or less 1.0 or less 0.3 or less 1.0 or less 0.3 or less
○ ○
Copper (mgCu/l) 0.3 or less 0.1 or less 1.0 or less 1.0 or less 0.1 or less 1.0 or less 0.1 or less 1.0 or less 0.1 or less ○
Chloride ion (mgS
2-
/l)
Undetectable Undetectable Undetectable Undetectable Undetectable Undetectable Undetectable Undetectable Undetectable
○
Ammonium ion (mgNH
4
+
/l) 1.0 or less 0.1 or less 1.0 or less 1.0 or less 0.1 or less 0.3 or less 0.1 or less 0.1 or less 0.1 or less
○
Residual chlorine (mgCl/l) 0.3 or less 0.3 or less 0.3 or less 0.3 or less 0.3 or less 0.25 or less 0.3 or less 0.1 or less 0.3 or less
○
Free carbon (mgCO
2
/l) 4.0 or less 4.0 or less 4.0 or less 4.0 or less 4.0 or less 0.4 or less 4.0 or less 0.4 or less 4.0 or less
○
Stability index 6.0 to 7.0 - - - - - - - -
○ ○
S
ta
nd
ar
d it
em
R
efe
re
nc
e it
em
Tendency
(2)
Corrosion
Scale
formation
[Greater than 20°C,
less than 60°C]
Make up
water
Low-grade medium temperature
water system
Cooling water system
(4)
Circulation
Circulation
water
Make up
water
Once-
through
water
Chilled water system
Item
(1) (6)
[20°C or
lower]
Warm water system
(3)
High-grade medium temperature
water system
[Greater than 60°C,
less than 90°C]
Make up
water
Make up
water
Water Quality Management