Specifications

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FORM 160.80-NOM1
YORK INTERNATIONAL
Liquid refrigerant will be visible in the evaporator sight
glass. The refrigerant level cannot be properly deter-
mined by viewing the liquid refrigerant level in the evapo-
rator sight glass.
All YS Chillers shipped Form 1 are charged with the
correct amount of refrigerant. Under some operating
conditions the chiller may appear to be overcharged or
undercharged with refrigerant. Consult with the YORK
Factory prior to removing or adding refrigerant. The
liquid line isolation valve may have to be partially throttled
to prevent overfeeding the evaporator in some applica-
tions and under certain operating conditions.
Definitions:
Evaporator Approach = (S.E.T) - (L.E.L.T)
Discharge Superheat = (C.D.G.T) - (S.C.T)
Where:
S.E.T. = Saturated Evaporator Temperature
L.E.L.T. = Leaving Evaporator Liquid Temp.
C.D.G.T. = Compressor Discharge Gas Temp.
S.C.T. = Saturated Condensing Temperature
These values can be obtained from the Graphic Control
Center. Refer to Graphic Control centerOperating In-
structions, Form 160.80-O1.
REFRIGERANT CHARGING
Should it become necessary to add refrigerant charge
to a YORK YS Chiller; add charge until the evaporator
approach and refrigerant gas discharge superheat are
at within the values listed in Table 9.
A charging valve is located in the liquid line below the
evaporator. The size of the charging connection is ¾
inch male flare. Purge air and non-condensables from
the charging hose. Only add new refrigerant, or refrig-
erant that has been tested and certified to meet Ameri-
can Refrigeration Institute Standard (ARI-700).
FILTER DRIER REPLACEMENT
The filter driers should be changed annually or when
excessive amount of oil is indicated in the refrigerant
charge.
When the filter driers require changing the chiller must
be shut off.
1. Close the (5) service isolation valves identified in
schematic drawing, Figure 23.
2. Carefully remove the insulation on the (2) filter dri-
ers located on the eductor block.
3. Relieve the pressure from the circuit using the pres-
sure access fitting located on the side of the educ-
tor block. Connect a refrigeration pressure hose to
the pressure access port and drain the oil and re-
frigerant into a suitable refrigerant recovery con-
tainer.
4. Loosen the Rota-Lock® Nuts at each end of the
(3) filter driers. Remove the filter driers.
5. Teflon® seal washers are used to seal the filter drier
connections. These washers must be replaced when
the filter driers are replaced.
6. Tighten the Rota-Lock® Nuts at each end of the
three filter driers to a torque of 60 ft-lb.
7. Evacuate the air from the oil filter to 500 microns
PSIG.
8. Open the five hand isolation valves. The chiller is
now ready to be placed back into service.
MOTOR
Inspect the motor at regular intervals. Keep the motor
clean and vent openings clear. Follow the original motor
manufacturer recommendation for lubricating the mo-
tor bearings. If the chiller is exposed to dusty and dirty
conditions during installation, lubricate the motor bear-
ings ahead of the suggested schedule.
DETERMINING CORRECT REFRIGERANT
CHARGE LEVEL
The refrigerant charge level is correct when the mea-
sured evaporator approach and discharge refrigerant
gas superheat are within the values listed in Table 9.
TABLE 9 – REFRIGERANT CHARGE LEVEL
CONDITION
R-22 R-134a
REFRIGERANT REFRIGERANT
COMFORT COOLING APPLICATIONS
EVAPORATOR
1°F-5°F1°F-5°F
APPROACH
DISCHARGE
35°F-45°F12°F-18°F
SUPERHEAT
BRINE (ICE MAKING) APPLICATIONS
EVAPORATOR
4°F-8°F4°F-8°F
APPROACH
DISCHARGE
45°F-65°F24°F-36°F
SUPERHEAT
IMPORTANT: The chiller must be at
design operating conditions and full
load operation before the correct re-
frigerant charge level can be properly
determined.
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