York MILLENNIUM YCAS 250 Manual Download

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YORK INTERNATIONAL

FORM 201.18-NM3

INSTALLATION

LOCATION REQUIREMENTS

To achieve optimum performance and trouble-free ser-
vice, it is essential that the proposed installation site
meets with the location and space requirements for the
model being installed. For dimensions, weight and
space requirements, including service access details,
refer to the Technical Data Section.

It is important to ensure that the minimum service ac-
cess space is maintained for cleaning and maintenance
purposes.

OUTDOOR INSTALLATIONS

The units can be installed at ground level, or on a
suitable rooftop location. In both cases an adequate
supply of air is required. Avoid locations where the
sound output and air discharge from the unit may be
objectionable.

The location should be selected for minimum sun ex-
posure and away from boiler flues and other sources of
airborne chemicals that could attack the condenser coils
and steel parts of the unit.

If located in an area which is accessible to unautho-
rized persons, steps must be taken to prevent access to
the unit by means of a protective fence. This will help
to prevent the possibility of vandalism, accidental dam-
age, or possible harm caused by unauthorized removal
of protective guards or opening panels to expose rotat-
ing or high voltage components.

For ground level locations, the unit must be installed
on a suitable flat and level concrete base that extends
to fully support the two side channels of the unit base
frame. A one-piece concrete slab, with footings extend-
ing below the frost line is recommended. To avoid noise
and vibration transmission the unit should not be se-
cured to the building foundation.

On rooftop locations, choose a place with adequate
structural strength to safely support the entire operat-
ing weight of the unit and service personnel. The unit
can be mounted on a concrete slab, similar to ground
floor locations, or on steel channels of suitable strength.
The channels should be spaced at the same centres as
the vibration mounting holes in the unit base frame and
must be at least 4-3/4" (120 mm) wide at the contact

points. This will allow vibration isolators to be fitted if
required.

Any ductwork or attenuators fitted to the unit must not
have a total static pressure resistance, at full unit air-
flow, exceeding the capability of the fans installed in
the unit.

INDOOR INSTALLATIONS

The unit can be installed in an enclosed plant room
providing the floor is level and of suitable strength to
support the full operating weight of the unit. It is es-
sential that there is adequate clearance for airflow to
the unit. The discharge air from the top of the unit must
be ducted away to prevent recirculation of air within
the plant room. If common ducts are used for fans, non-
return dampers must be fitted to the outlet from each
fan.

The discharge ducting must be properly sized with a
total static pressure loss, together with any intake static
pressure loss, less than the available static pressure ca-
pability for the type of fan fitted.

The discharge air duct usually rejects outside the build-
ing through a louver. The outlet must be positioned to
prevent the air being drawn directly back into the air
intake for the condenser coils, as such recirculation will
affect unit performance.

LOCATION CLEARANCES

Adequate clearances around the unit(s) are required for
the unrestricted airflow for the air-cooled condenser
coils and to prevent recirculation of warm discharge
air back onto the coils. If clearances given are not main-
tained, airflow restriction or recirculation will cause a
loss of unit performance, an increase in power con-
sumption and may cause the unit to malfunction. Con-
sideration should also be given to the possibility of
down drafts, caused by adjacent buildings, which may
cause recirculation or uneven unit airflow.

For locations where significant cross winds are ex-
pected, such as exposed roof tops, an enclosure of solid
or louver type is recommended to prevent wind turbu-
lence interfering with the unit airflow.