York Millenium YK D Series, Руководство по установке, Страница: 24 / 28

24 YORK INTERNATIONAL
LD02139
FIG. 8 – TYPICIAL REFRIGERANT VENT PIPING
Stop Valves
Stop valves may be provided (by others) in the cooler
and condenser water piping adjacent to the unit to fa-
cilitate maintenance. Thermometer wells and pressure
taps should be provided (by others) in the piping as
close to the unit as possible to facilitate operating check.
Flow Switches (Field Installed)
A flow switch or pressure differential control in the chilled
water line(s) adjacent to the unit is an accessory fur-
nished for connection to the control center. If a flow
switch is used, it must be directly in series with the chiller
and sensing only water flow through the chiller. The dif-
ferential switch must sense pressure drop across the
unit.
Drain and Vent Valves
Drain and vent valves (by others) should be installed in
the connections provided in the cooler and condenser
liquid heads. These connections may be piped to drain
if desired.
Checking Piping Circuits and Venting Air
After the water piping is completed, but before any wa-
ter box insulation is applied. Tighten and torque (to main-
tain between 30 and 60 ft. lbs.) the nuts on the liquid
head flanges. Gasket shrinkage and handling during
transit cause nuts to loosen. If water pressure is ap-
plied before tightening is done, the gaskets may be
damaged and have to be replaced. Fill the chilled and
condenser water circuits, operate the pumps manually
and carefully check the cooler and condenser water
heads and piping for leaks. Repair leaks as necessary.
Before initial operation of the unit both water circuits
should be thoroughly vented of all air at the high points.
REFRIGERANT RELIEF PIPING
Each unit is equipped with pressure relief valves located
on the condenser and on the evaporator for the pur-
pose of quickly relieving excess pressure of the refrig-
erant charge to the atmosphere as a safety precaution
in case of an emergency, such as fire.
Refrigerant relief vent piping (by others), from the relief
valves to the outside of the building, is required by code
in most areas and should be installed on all chillers.
The vent line should be sized in accordance with the
ANSI/ASHRAE-15, or local code. The vent line must
include a dirt trap in the vertical leg to intercept and
permit clean out and to trap any vent stack condensa-
tion. The piping MUST be arranged to avoid strain on
the relief valves, using a flexible connection, if neces-
sary.
UNIT PIPING
Compressor lubricant piping and system external pip-
ing are factory installed on all units shipped assembled.
On units shipped dismantled, the following piping should
be completed under the supervision of the YORK rep-
resentative: (1) the lubricant piping to oil sump and oil
cooler and system oil return connections using material
furnished. See Form 160.49-N6.
CONDENSER
COOLER
VENT TO ATMOSPHERE
SUPPORT VENT PIPING TO AVOID
STRAIN ON RELIEF PIPING
FLEXIBLE CONNECTOR
FLANGED JOINT
TO PERMIT PIPING
DISASSEMBLY
SEE NOTE
CONDENSATION
TRAP
DUAL RELIEF
VALVES
NOTE: SHELLS MAY BE FURNISHED WITH
ONE OR TWO RELIEF VALVES,
DEPENDING ON SHELL SIZE.