75
Installation
DHW tank supplies hot water from tap water. Domestic hot
water is only used when tap water is connected.
added, water will be contaminated when heat exchanger coil
leaks.
When water hardness is more than 250-300 ppm, recommend
using softened water to reduce DHW tank scale.
Try to avoid long runs of water piping between the tank and the
DHW installation in order to decrease possible temperature
losses.
lf the domestic cold water entry pressure is higher than the
DHW tank’s design pressure, a pressure reducer must be
After used for a while (depend on local water quality and use
frequency), clean DHW tank and remove scales.
a.
b.
DHW tank.
When scales are removed, temperature in DHW tank
may be a little high, it should prevent burns or drainage
equipment damaged.
c.
Close drainage valve after cleaning several minutes with
after DHW tank is full of water. Power on and get back to
work.
8.1.8.5
WATER CONTROL
It is necessary to analyse the quality of water by checking
pH, electrical conductivity, ammonia ion content, sulphur
content, and others. The following is the recommended
standard water quality.
Item
Chilled water system Tendency (1)
Circulating
water (20°C
less than)
Supply water
Corro-
sion
Depos-
its of
scales
Standard Quality pH
(25 °C)
6.8 ~ 8.0 6.8 ~ 8.0
Electrical Conductivity
(mS/m) (25 °C)
{µS/cm} (25 °C)
(2)
Less than 40
Less than 400
Less than 30
Less than
300
Chlorine Ion
(mg CI¯/I)
Less than 50 Less than 50
Sulphur Acid Ion
(mg H
4
SO¯/I)
Less than 50 Less than 50
The amount of Acid
consumption (pH 4.8)
(mg CaCO
3
/I)
Less than 50 Less than 50
Total Hardness
(mg CaCO
3
/I)
Less than 70 Less than 70
Calcium Hardness
(mg CaCO
3
/I)
Less than 50 Less than 50
Silica L (mg SIO
2
/I) Less than 30 Less than 30
Reference Quality
Total Iron (mg Fe/I)
Less than 1.0 Less than 0.3
Total Copper
(mg Cu/I)
Less than 1.0 Less than 0.1
Sulphur Ion (mg S
2¯
/I) It shall not be detected
Ammonium Ion (mg
NH
4
+
/I)
Less than 1.0 Less than 0.1
Remaining Chlorine
(mg CI/I)
Less than 0.3 Less than 0.3
Floating Carbonic Acid
(mg CO
2
/I)
Less than 4.0 Less than 4.0
Index of Stability 6.8 ~ 8.0 -
the tendency of corrosion or deposits of scales.
the former unit.
To Next Page
Loading...
