Air Source Screw Water Chiller Unit – Installation Operation and Maintenance Manual
109
Method of charging and evacuating refrigerants:
1.
After evacuating the units, use the needle valves of the stop valves on both ends of the drier-filter to
charge refrigerants.
2.
Evacuate refrigerants from the needle valves of the stop valves.
3.
Use a special refrigerant charging and evacuating device to charge refrigerants (R134a) to or
evacuate refrigerants from the units.
Charge the R134a evacuated from the units into a fluid reservoir, which is designed to withstand the
pressure of the units and comply with related standards of pressure vessels. It is forbidden to drain the
R134a directly into air or sewers.
Determining the Amount of Refrigerants:
To check whether the refrigerant charge of the water chiller unit is insufficient, view the mirror on the
supplying line and evaporation pressure by performing the following steps:
Check that the unit operates at full load when the loop is running at full load. See the steps described
in the control section.
When the unit operates at full load, ensure that the outlet water temperature of the evaporator ranges
from 5.5°C to 6.5°C.
View the mirror on the supplying line.
The refrigerant charge is appropriate if the mirror is clear without bubbles, the liquid lens of the compressor
is at the full level, and the evaporation temperature is within the normal range.
However, the refrigerant charge is insufficient if bubbles appear at the bottom of the mirror and the
evaporation temperature is below the normal range.
1
0
.6 Routine Maintenance Items
Maintenance Items
Maintenance
Frequency
Acceptability Baseline
(Handling Method)
Remarks
A. Generality
Noise
Anytime
Check whether an abnormal sound can be
heard.
View the
items
1
meter to
the center
of
the
water
chiller
unit.
Vibration
Anytime
Check whether the amplitude of vibration
of auxiliary pipes and components is too
high.
Voltage
Anytime
The voltage must be within ±10% of the
rated voltage.
B.
Unit
exterior
Stain
Anytime
Keep clean always.
Rust
Anytime
Use an iron brush to remove the rust and
then apply anticorrosive paint.
Looseness
Anytime
Tighten screws.
