Daikin UAL-A Series - Water System Installation

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Water System Installation
Water quality requirements
Water in the water system must be softened to prevent scale in the heat exchanger and affecting the heat
exchanger performance. Water not softened can also cause scale in the water pipes and cause the water
resistance to increase. This affects the water ow and the performance of the water pump. Softened water must
meet the following requirements.
Item Benchmark value
Tendencies
Corrosion Scaling
Benchmark items
pH (25°C) 7.0 - 9.0
○ ○
Conductivity
(25°C)
μS/cm < 800
○ ○
Cl
-
mg (Cl
-
)/L < 200
○
SO
4
2-
mg (SO
4
2-
)/L < 200
○
Acid consumption
mg (CaCO
3
)/L < 100
○
(pH = 4.8)
Total hardness mg (CaCO
3
)/L < 200
○
Reference items
Fe mg (Fe)/L < 1.0
○ ○
S
2-
mg (S
2-
)/L 0
○
NH
4
+
mg (NH
4
+
)/L < 1.0
○
SiO
2
mg (SiO
2
)/L < 50
○
NOTE:
○
REPRESENTS FACTORS THAT MAY CAUSE CORROSION OR SCALING.
Water System Installation Schematic Diagram
Connecting Water Pipes
No water pump is provided as an accessory. A proper water pump must be installed to overcome resistance of the
water pipes.
■ Water pressure gauges and thermometers must be installed at the water inlets and outlets to facilitate the
reading of unit operation status.
■ The heat exchanger at the water side is made of stainless steel. Water scale may accumulate depending on
the water quality and must be cleared using chemicals from time to time. Therefore, a chemical cleaning pipe
connector needs to be installed at the water pipes (see the following gure).