Water System Installation - York YVAG012 Operation & Maintenance Manual

WATER SYSTEM INSTALLATION

Chilled liquid piping specification
General – When the unit(s) has been located in its final
position, the unit water piping may be connected.
Normal installation precautions should be observed in
order to receive maximum operating efficiencies. All
chilled water evaporator piping must comply with local
plumbing codes and ordinances in all aspects.
Since elbows, tees and valves decrease pump capacity,
all piping should be kept as straight and as simple as
possible. All piping must be supported independent of
the unit.
The following considerations of piping specification
should be observed:
a) The pipe diameter of the pipes inlet and outlet unit
shall not be smaller than the joint specification (DN25).
Also piping of DN32 or above is recommended
b) Piping to the inlet and outlet connections of the
unit should include high-pressure rubber hose or piping
loops to ensure against transmission of water pump
vibration. The necessary components must be obtained
in the field.
c) PP-R material is recommended for the water
supply and return piping of the unit for the household
water system. It will be beneficial, as the possibility of
the filth blockage and the water resistance will decrease.
d) Galvanized steel pipe (not recommended) shall be
designed as screwed connection. When the pipe
diameter is larger than DN100, clamp, flange or welded
joint can be applied for connection.
e) For welded connection (not recommended)
applied for piping, antiseptic treatment (rust cleaning
before painting) shall be conducted to the surface of
welded joint and heat-effected area.
f) Galvanized steel piping, PP-R piping and the
corresponding screwed joints are indicated in piping
specification of TABLE 2 , and just for reference only.
Chilled liquid piping installation
Water pipeline connection shall observe relevant
installation regulations. Piping should be kept free of
foreign matter.
The piping to and from the chiller must be designed to
suit the individual installation. It is important that the
following considerations are observed:
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Cooke Industries - Phone: +64 9 579 2185
a) The operating flow rate of the unit shall not exceed
40% of rated flow for each unit type, too large or too
small water flow rate would affect the normal use of the
unit.
b) The water flow direction of the unit shall be
connected according to the inlet and outlet pipe marks
on the unit, otherwise the performance of the unit might
be affected.
c) The pipeline must have independent support and
should not be placed on the unit.
d) Hand stop valves, thermometers and pressure
gauges should be installed in both inlet and outlet line
for adjusting water flow rate and facilitating servicing.
e) The external water pump and its controller cabinet
need to be installed on site; the main engine provides
230V~ control signal to realize the linkage of the unit
and the water pump. A stand-by pump shall be installed
on the site in case that the pump in common use would
break down and affect the unit operation;
f) The water filter included the unit shall be installed
on the inlet pipe of each unit to prevent the cooler from
large particles entering, which could cause damage to
the evaporator.
g) A water filter of no less than 60 mesh per inch shall
be installed on the inlet pipe of the external water pump
to guarantee reliable operation of the water pump.
h) At least one vent valve should be installed at the
highest points in the chilled water pipeline to allow any
trapped air to be exhausted. It can avoid generating
cavitation noise and damaging the water pump.
i) Auto-supply valve shall be installed for closed
type of water system (without open expansion tank) in
case that the unit could not operate normally when the
system is short of water. It is suggested to set the outlet
water pressure of the auto-supply valve 0.3bar higher
than the static pressure of the system, but the set value
shall be lower than the supplementing water pressure
(the source of the water supplementing), or it would not
conduct normal water supplement. The auto-supply
valve is usually installed at the return water line of the
system; heat isolation measures shall be conducted to
the water supplement pipeline and water supply valve
to against freeze-up in winter.
j) The chilled water lines that are exposed to ambient
Email: sales@cookeindustries.co.nz
FORM NO.: 6U5M-A11M-NB-EN
Web: www.cookeindustries.co.nz
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