Johnson Controls YEWS Series, Installation, Operation And Maintanance Instructions

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Oil Charging Procedure
The oil should be charged into the oil separator using the
YORK Oil Charging Pump. To charge oil, proceed as
follows:
1. The unit should be shut down.
2. Immerse the suction connection of the oil charging
pump in a clean container of new oil and connect the
discharge conncetion to the compressor oil charging
valve.Do not tighten the connection at the charging valve
unless the air is forced out by pumping a few strokes of
the oil pump. Filling the lines with oil to prevent air from
being pumped into the system.
3. Open the oil charging valve and pump appropriate oil
(according the data in oil charge table) into the system.
Then close the charging valve and disconnect the hand oil
pump.
4. As soon as oil charging is completed, closed the power
supply to the starter to energize the oil heater. This will
keep the concentration of regrigerant in the oil to a
minimum.
Oil temperature control
Automatic oil temperature control is accomplished by
liquid injection into compressor/motor assembly. A
solenoid valve will be opened when the discharge
temperature increased to setpoints (only ITS&HP unit
need this function).
8.4 Oil filter
For YEWS100H/130H/170H/200H/210H , a single oil
filter is prov-ided as an standard equipment. Detail
operations refer to the compressor operation and service
manual.
For YEWS100P/130P/170P/200P/215P a replaceable oil
filter is equipped in the external oil supply line(as below
picture) . Please make sure all the valves are in open
status after the replacement of oil filter.
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YEWS-E Water Cooling Screw Chiller/Heat Pump
58
8.5 Condenser and Evaporator
General
Maintenance of condenser and evaporator shells is impotant
to provide trouble free operation of the unit. The water side
of the tubes in the shell must be kept clean and free from
scale.Proper maintenance such as tube cleaning, and testing
for leaks, is covered on the following pages.
Chemical water treatment
Since the mineral content of the water circulated through
evaprators and condensers varies with almost every source of
supply, it is possible that the water being used may corrode
the tubes or deposit heat resistant scale in them.
Reliable water treatment companies are available in most
large cities to supply a water treating process which will
greatly reduce the corrosive and scale forming properties of
almost any type of water.
As a preventive measure against scale and corrosion and
prolong the life of evaporator and condenser tubes, a
chemical analysis of water should be made, preferably before
the system is installed. A reliable water treatment company
can be consulted to determine whether water treatment is
necessary, and if so, to finish the proper treatment for
particular water condition.
Condenser and evaporator water side tube cleaning
procedure