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Air and/or moisture in the refrigerant system can have undesirable effects as indicated below:
●
Higher system operating pressures.
●
Higher system operating current.
●
Performance and efficiency loss
●
Moisture in the refrigerant circuit may freeze and
cause blockages in the system
.
●
Water may lead to corrosion of
key components in the refrigeration system.
Therefore, the system components, indoor, outdoor and refrigerant pipe between the units must be
leak tested and evacuated thoroughly to remove any non-condensables and/or moisture from the system.
Air purging with vacuum pump
●
Preparation:
Check that all piping (both liquid and gas side pipes) between the indoor and outdoor units
have been properly connected and all wiring has been completed. Remove the service valve
caps from both the gas and the liquid side on the outdoor unit. Note that both the liquid and
gas side service valves on the outdoor unit are to be kept closed at this stage.
REFRIGERATION
Air purging
Please refer to Page 8 of this manual for specific pipe length and height specifications.
The outdoor unit is charged for a
nominal 10m pipe length for each indoor
unit
up to the maximum no. of indoor units (2-Head Outdoor 20m, 3-Head Outdoor 30m, 4-Head
Outdoor 40m & 5-Head Outdoor 50m). The total system refrigerant charge must be adjusted
REMOVE Refrigerant
Less than 10m pipe length
More than 10m pipe length
System Refrigerant Adjustment - Calculated for each Indoor Unit
ADD Refrigerant
15g/m for Ø 6.35mm Liquid Line
15g/m for Ø 6.35mm Liquid Line
or
according to the table below:
Indoor
Unit 1 2.0 10 0 Ø 6.35 15 0
FIVE Indoor Units (2.0+2.0+2.6+3.5+7.0kW) - 5 Head Outdoor Unit pre-charged for 50m
Size
(kW)
Actual
Length
(m)
Pre-charged Pipe
Length Variance
(m)
Liquid Line
(mm)
Size
Indoor Unit
(g/m)
Charge Adjustment
System Charge
(g)
Adjustment
Unit
Unit 2 2.0 12 2 Ø 6.35 15 30
Unit 3 2.6 6 -4 Ø 6.35 15 -60
Unit 4 3.5 20 10 Ø 6.35 15 150
Unit 5 7.0 14 4 Ø 9.52 30 120
Total System Length 62 Total System Refrigerant Adjustment (g) 120
In this example, an additional 240g of refrigerant is required to be ADDED to the system
System charging
●
Example 1
