MCAC-CTSM-2014-03 DX type water-cooled screw chiller (PCB Control)
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and break the vacuum with refrigerant gas to a saturated pressure above freezing.
With a system gas pressure higher than the equivalent of a freezing temperature, invert the charging
cylinder and elevate the drum above the condenser. With the drum in this position, valves open, water
pumps operating, liquid refrigerant will flow into the condenser. Approximately 75% of the total
requirement estimated for the unit can be charged in this manner.
After 75% of the required charge has entered the condenser, reconnect the refrigerant drum and
charging line to the service valve on the bottom of the evaporator. Again purge the connecting line, stand
the drum with the connection up, and place the service valve in the open position.
Before replacing electronic expansion valve or thermal expansion valve of the system, pressure sensor
sampling shut valve, low pressure pipeline, etc. force the refrigerant in the liquid part of the system.
The particular steps are: (take careful consideration before continuing with the following steps)`
a Close the dry filter angle valve of the system.
b Start up the unit, and emergently stop the unit when the gas in the system is below 0.5bar.
c Close the liquid/air valve of the compressor.
d Discharge the residual refrigerant in the gas system.
e Carry on replacement of the parts of the system.
f
After the replacement, extract vacuum in the gas part.
g After the vacuum extraction, keep the negative voltage until the resumed vacuum in the unit meets
the requirements.
h Open the angle valve of liquid system and compressor liquid/air stop valve to ensure the loop of the
entire system is unobstructed.
i
Add proper amount of refrigerant, generally 5~10k.
Oil Charging/Low Oil Recharging
Pre-cautions in changing of oil
1.
Use only qualified oil and do not mix different brand of oil together. Different kinds of refrigerant should
match different kinds of oil, note that some synthetic oil is incompatible with mineral oil.
2. When using the synthetic oil for the chiller system, be sure not to expose the oil to atmosphere for a
long time, it is also necessary to vacuum the system completely when installing the compressor.
3. In order to ensure no moisture inside the system, it is suggested to clean the system by charging it
with dry Nitrogen and then vacuum the system repeatedly as long as possible.
4. It is essential to change for new oil especially after the motor burns out; the acidity debris still remain
inside the system so clean work must be done to overhaul the system. Check the oil acidity after 72
hours of operation and then change it again until the oil acidity is in the standard value.
5. Contact local distributor/agent for concerning unqualified oil to be used.
Oil change
1. Change oil periodically: Check the lubrication oil for every 10,000 hours of continuous running. For the
first operation of the compressor, it is recommended to change oil and clean oil filter after running at
