Refrigerant Leak Checking; Pressure Connections; Condenser Tubes; Condenser Water Side Tube Cleaning Procedure - York MILLENNIUM YS Manual

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 re-
claimed refrigerant that has been tested and verified to
meet ARI 700.

REFRIGERANT LEAK CHECKING

Periodic refrigerant leak checking must be part of a
comprehensive maintenance program. Leak check the
entire chiller using a calibrated electronic leak detector.
Confirm leaks with soap bubbles that are found using
the electronic leak detector.
Check refrigerant relief valve piping and tube rolled joints
as part of the comprehensive refrigerant leak checking
program.
Repair leaks before adding refrigerant.

PRESSURE CONNECTIONS

All threaded pressure connections used on the York YS
Chillers are SAE straight thread, O-ring face seal type
fittings or Primore Rotalock
The O-ring straight thread fittings and O-ring face seal
fittings are designed and used in accordance with SAE
J1926 and J1453. Should it become necessary to re-
move a fitting the O-ring(s) should be replaced. Make
certain to use only neoprene replacement O-rings. O-
rings can be ordered from the local York Service Of-
fice.
Pipe sealant compounds are not required with SAE type
O-ring fittings. The O-ring seal accomplishes the pres-
sure sealing. Lubricate the O-ring with compressor oil
prior to assembly.
All filter driers and angle shut off valves use Primore

Rotalock fittings. These fittings use a Teflon

seal washer. The Teflon fiber seal washers should be
replaced each time the filter driers are changed.

CONDENSER TUBES

The standard condenser tubes used in York YS Chillers
are internally enhanced copper tubes.
YORK INTERNATIONAL

fittings.

fiber
If the equipment is located in an un-
heated area that is susceptible to freez-
ing, the water must be drained from
the condenser to prevent tube failure
from freezing.
Proper condenser water treatment can eliminate or sig-
nificantly reduce the formation of scale on the water-
side of the condenser tubes.
Maintain a minimum condenser water flow rate of at
least 3.33 ft/sec. Water velocity should not exceed 12
ft/sec.
Condenser tubes must be maintained to provide proper
chiller operation. Condenser Approach Temperature is
a useful tool to monitor the performance of the con-
denser. By recording and logging the Condenser Ap-
proach Temperature as part of the chiller maintenance
program, this will provide a warning that the waterside
condenser tubes are fouled and require cleaning.
Condenser Approach Temperature is the difference be-
tween the Condenser Leaving Water Temperature and
the Saturated Condensing Temperature.
If the approach increases above 10ºF (5.6ºC), or during
the annual condenser inspection and the tubes are ob-
served to be fouled, the tubes will require cleaning. For
condenser fluids other than water consult with the local
York Field Service Office for the correct condenser ap-
proach.
CONDENSER WATER SIDE TUBE CLEANING
PROCEDURE
Two methods are used for waterside tube cleaning to
remove the scale; chemical and mechanical cleaning
procedures. The composition of the scale will deter-
mine which method will be most effective to remove
the scale and dirt.
Consult with the local York Field Service Office for a
recommendation of the method(s) used in the local area.

CHEMICAL CLEANING PROCEDURE

Chemical cleaning is an effective method to remove
scale from internally enhanced copper tubes. How-
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