Mitsubishi Electric City Multi CMB-WP108V-G, Service Manual

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[
I
Read Before Servicing ]
- 16 - HWE1113B GB
2. Notes on corrosion
(1) Water quality
It is important to check the water quality beforehand. See table below (Circulating water/Makeup Water Quality Standards).
(2) Debris in the water
Sand, pebbles, suspended solids, and corrosion products in water can damage the metal pipe and heat exchanger on the
HBC controller and may cause corrosion. When installing, prevent debris from entering the water. If there is debris in the wa-
ter, perform debris removal operation after test run by cleaning the strainers inside the HBC controller. (Refer to other sections
for how to perform a test run.)
(3) Connecting pipes made of different materials
Connecting pipes used for HBC controller and indoor unit are copper alloy pipes. If steel pipes are connected tothe pipes, the
contact surface will corrode. Do not use steel pipes to avoid corrosion.
(4) Residual air
Residual air in the pipe results in water pump malfunction, noise, or water pipe corrosion in the water circuit. Ensure air is
purged before use. (Refer to other sections for how to perform air vent operation.)
pH (25°C[77°F])
Electric conductivity
Chloride ion
Sulfate ion
Acid consumption (pH4.8)
Total hardness
Calcium hardness
Ionic silica
Iron
Copper
Sulfide ion
Ammonium ion
Residual chlorine
Free carbon dioxide
Ryzner stability index
Standard items
Reference items
Items
Lower mid-range
temperature water system
7.0 ~ 8.0
30 or less
[300 or less]
50 or less
50 or less
50 or less
70 or less
50 or less
30 or less
1.0 or less
1.0 or less
not to be
detected
0.3 or less
0.25 or less
0.4 or less
–
7.0 ~ 8.0
30 or less
[300 or less]
50 or less
50 or less
50 or less
70 or less
50 or less
30 or less
0.3 or less
0.1 or less
not to be
detected
0.1 or less
0.3 or less
4.0 or less
–
Tendency
Recirculating
water
[68<T<140°F]
[20<T<60°C]
Make-up
water
Corrosive
Scale-
forming
Reference : Guideline of Water Quality for Refrigeration and Air Conditioning
Equipment. (JRA GL02E-1994)
(mg Cl
-
/ )
(mg SO
4
2- / )
(mg CaCO
3
/ )
(mg CaCO
3
/ )
(mg CaCO
3
/ )
(mg SiO
2
/ )
(mg Fe/ )
(mg Cu/ )
(mg S
2-
/ )
(mg NH
4
+
/ )
(mg Cl/ )
(mg CO
2
/ )
(mS/m) (25°C[77°F])
(μS/cm) (25°C[77°F])