Daily Service And Maintenance; Water Quality - Daikin VRV-WII FXYCP30MY1 Installation Procedure

1 Installation of outdoor
1 - 6 Handling of the plate type heat exchanger
1 - 6 - 3

Daily service and maintenance

1 Management of water quality
The plate type heat exchanger has a structure that does not permit dismantling and cleaning, or replacing any parts. Please pay attention carefully
to the quality of water to be used for the plate type heat exchanger in order to prevent corrosion and sticking of scale.
The water to be used for the plate type heat exchanger should have at least the quality as specified in the table below.
When using any corrosion prevention agent, scale depressant agent, etc. such agent should have no corrosive features against stainless steel
and copper.
2 Management of chilled water flow rate
If the chilled water flow rate is not enough, it will result in the freezing damage to the plate type heat exchanger.
Check for any clogging of the strainer, any air being caught, any reduction in the flow rate due to failure of circulation pump by measuring the
temperature and pressure differences at the inlet and outlet ports of the plate type heat exchanger. If the aged difference in the temperature or
pressure has increased beyond the proper range, the flow rate should have decreased. Stop the operation and remove the cause before restarting
the operation.
3 Steps to be taken when a freezing protection device was activated
When the freezing protection device should be activated during operation, remove the cause without fail before restarting the operation. If the
freezing protection device has been once activated, a partial freezing has occurred. If you restart the operation without removing the cause, the
plate type heat exchanger will be closed and the ice cannot be melted, and in addition, the freezing process will be repeated resulting in any
damage to the plate type heat exchanger, leading to any such accidents that the refrigerant starts leaking or water starts entering the refrigerant
circuit.
1 - 6 - 4

Water quality

Water quality standards for chilled water, hot water and make-up water (4) (6)
ITEM (5)
pH (25°C)
Electrical conductivity (mS/m) (25°C)
-
Chloride ions (mg Cl /l)
2-
Sulfate ions (mg SO /l)
4
Acid consumption (pH 4.8) (mg CaCO
Total hardness (mg CaCO
3
Calcium hardness (mg CaCO
Ionic-state silica (mg SiO /l)
2
Iron (mg Fe/l)
Copper (mg Cu/l)
2
Sulfite ion (mg S /l)
+
Ammonium ion (mg NH /l)
4
Residual chlorine (mg CL/l)
Free carbon dioxide (mg CO
Stability index
N
OTES
1 The circle marks in the columns for corrosion or scale to develop.
2 Corrosion has a tendency to occur when water temperature is high (40°C or higher), and if metals with no protective coating whatever are directly
exposed to water, it would be a good idea to take effective measures against corrosion such as adding a corrosion inhibitor or deaeration treatment.
3 In a condenser water circuit that uses a closed cooling tower, the closed circuit circulating water and make-up water must satisfy its water quality
standards for the hot water system, and passing water and make-up water must satisfy those for the circulation type cooling water system.
4 Supply or make-up water should be tap water (clean water), industrial water and underground water except for purified water, neutral water and
softened water or the like.
5 The fifteen items in the table above represent typical causes of corrosion and scale.
6 Passing water may cause corrosion.
Do not use passing water.
10
• Installation procedure
Cooling water system (3)
Circulation system
Circulation water
6.8 to 8.2
Less than 80
Less than 200
Less than 200
/l) Less than 100
3
Less than 200
/l)
/l) Less than 150
3
Less than 50
Less than 1.0
Less than 0.3
Shall not be
Less than 1.0
Less than 0.3
/l) Less than 4.0
2
6.0 to 7.0
®
• VRV Systems • Installation procedure
Hot water system (2)
Circulation water
(20°C ~ 60°C)
Make-up water
Standard items
6.0 to 8.0 7.0 to 8.0
Less than 30 Less than 30
Less than 50 Less than 50
Less than 50 Less than 50
Less than 50 Less than 50
Less than 70 Less than 70
Less than 50 Less than 50
Less than 30 Less than 30
Reference items
Less than 0.3 Less than 1.0
Less than 0.1 Less than 1.0
Shall not be Shall not be
Less than 0.1 Less than 0.3
Less than 0.3 Less than 0.25
Less than 4.0 Less than 0.4
- -
Tendency (1)
Make-up water Corrosion
7.0 to 8.0
Less than 30
Less than 50
Less than 50
Less than 50
Less than 70
Less than 50
Less than 30
Less than 0.3
Less than 0.1
Shall not be
Less than 0.1
Less than 0.3
Less than 4.0
-
Scale