Johnson Controls YEWS Series, Installation, Operation And Maintanance Instructions

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CONDITION
COMFORT COOING APPLICATIONS
EVAPORATOR APPROACH
DISCHRGE SUPERHEAT
BRINE(ICE MAKING) APPLICATIONS
EVAPORATOR APPROACH
DISCHRGE SUPERHEAT
R134a REFRIGERANT
1
℃
~3.5
5
℃
~15
℃
1
℃
~4.5
℃
6
℃
~20
℃
℃
YORK OIL TYPE
L(W)
MOISTURE
CONTENT ppm Total Acid Number
mgKOH/ml
< 300ppm
< 0.5
approach and refrigerant gas discharge superheat are at
within the values listed in Table 8-1.
A charging valve is located in the liquid line below the
evaporator. The size of the charging connection is 1/4 inch
male flare. Purge air and non-condensables from the
charging hose. Only add new refrigerant, or refrigerant
that has been tested and certified to meet American
Refrigeration Institute Standard (ARI-700).
（
suitable for
model D
）
TABLE 8-1 REFRIGERANT CHARGE LEVEL
8.3 Compressor oil
Yearly oil analysis is recommended to verify the
continued use of the compressor oil.
It is very important to take the oil sample after the oil
filter. The oil sample should not be left open to the
atmosphere for more than 15 minutes since it will absorb
moisture from the atmosphere and may yield erroneous
results.
Compressor oil should be changed when the oil analysis
indicates the oil has moisture and acid numbers are in
excess of the limits set in Table 8.2.
TABLE 8.2
–
COMPRESSOR OIL LIMITS
The YORK YEWS-E Chiller Compressors use rolling
element bearings (ball and roller bearings); no sleeve
bearings are used. Oil analysis that include metals may
cause confusion when the results are compared to other
equipment that utilize different bearing types. Iron and
copper are examples of metals, which will appear in oil
analysis that include metals. Other metals that may
appear are Titanium, Zinc, Lead, Tin and Silicon. These
metals should be ignored and are acceptable in quantities
of less than 100 ppm. If an oil analysis should indicate
high levels of Iron (more than 300 ppm) combined with
Chromium and Nickel (more than 50 ppm), consult your
local YORK Service Office
–
this could indicate bearing
damage and wear.
Changing Compressor Oil
Compressor oil is changed by draining oil from the oil
sump into a refrigerant recovery container. The oil sump
is under positive pressure at ambient temperatures.
Connect one end of a refrigeration charging hose to the
service valve located at the bottom of the oil sump;
connect the other end to an approved refrigerant recovery
cylinder. Open the valve and drain the oil from the oil
sump.
Charging units with Oil
The Oil Charge
YORK oil types approved for YEWS-E Units and the
quality of oil required is listed in Table 8-3.
UNIT TYPE
YEWS100
YEWS130
YEWS170
YEWS200
YEWS210
YEWS215
OIL TYPE
L*
L*
L*
L*
L*
L*
17
25
30
33
33
33
SYSTEM
QUANLITY(L)
* : HP unit use YORK
“
W
”
oil
YEWS-E Water Cooling Screw Chiller/Heat Pump
57