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c.Make s ure
t hat condensate
drain trap is filled with water
to ensure
proper drainage.
d. Make sure that all tools and miscellaneous
loose parts
have been removed.
e. Make sure that the start-up
checklist
has been
performed
and filled out.
NOTE:
Ensure
wiring
does not contact
any refrigerant
tubing.
START-UP
Use the following
information
and Start-Up
Checklist
to check out
unit PRIOR
to start-up.
Unit Preparation
Check
that
unit
has
been
installed
in
accordance
with
these
installation
instructions
and all @plicable
codes.
Compressor
Mounting
Compressors
are
internally
spring
mounted.
Do
not
loosen
or
remove
compressor
holddown
bolts.
Refrigerant
Service Ports
Each independent
refrigerant
system
has a total of 3 Schrader-type
service
gauge ports per circuit.
One port is located
on the suction
line, one on the compressor
discharge
line, and one on the liquid
line. Be sure that caps on the ports are tight.
Crankcase
Heater(s)
Crankcase
heaters
are energized
as long
as there is power
to the
unit and the compressor
is not operating.
IMPORTANT:
Unit
power
must
be on for 24 hours
prior
to
start-up.
Otherwise,
damage
to compressor
may result.
Compressor
Rotation
On 3-phase
units, it is important
to be certain the scroll compressor
is rotating
in the proper
direction.
To determine
whether
or not
compressor
is rotating
in the proper direction:
1. Connect
service
gauges
to suction
and discharge
pressure
fittings.
2. Energize
the compressor.
3. The suction
pressure
should drop and the discharge
pressure
should rise, as is normal
on any start-up.
If the suction
pressure
does not drop
and the discharge
pressure
does not rise to normal levels:
1. Note that the evaporator
fan is probably
also rotating
in the
wrong direction.
2. Turn off power
to the unit and install lockout
tag.
3. Reverse
any two of the unit power
leads.
4. Turn on power
to the unit.
The suction
and discharge
pressure
levels
should
now
move
to
their normal
start-up
levels.
NOTE:
When the compressor
is rotating
in the wrong
direction,
the unit makes
an elevated
level
of noise
and does
not provide
heating
or cooling.
EQUIPMENT
DAMAGE
HAZARD
Failure to follow
this caution
may result in equipment
damage.
Compressor
damage
will occur
if rotation
is not immediately
corrected.
Evaporator
Fan
Fan belt and variable
pulleys
are factory-installed
but may need to
be adjusted
for specific
applications.
Be sure that fans rotate in the
proper
direction.
See Appendix
A for fan performance
data.
See
Appendix
B
for
air
quantity
limits,
evaporator
fan
motor
specifications,
FIOP
static
pressures,
and fan RPM
for various
motor
pulley
settings.
To alter fan performance,
see Evaporator
Fan Performance
Adjustment
in the Service section.
Condenser
Fans and Motors
Condenser
fans
and
motors
are
factory
set.
Refer
to
Condenser-Fan
Adjustment
section,
as required.
Return-Air
Filters
Check that correct
filters are installed
in filter tracks. (See Table 1.)
Do not operate
unit without
return-air
filters.
NOTE:
For units with
4-in.
filter option,
units
are shipped
with
standard
2-in.
filters. To install 4-in.
filters, the filter spacers
must
be removed.
Outdoor-Air
Inlet Screens
Outdoor-air
inlet screens
must be in place before operating
unit.
Optional
EconoMi$er
IV
See Fig. 19 for EconoMi$er
IV component
locations.
The optional
EconoMi$er
IV comes from the factory fully wired and assembled.
No field wiring
or assembly
is required
for standard
outdoor
dry
bulb
changeover
operation.
Field wiring
of accessory
sensors
is
required
for different
operational
modes.
EconoMi$er
IV Standard
Sensors
Outdoor
Air Temperature
(OAT)
Sensor
The outdoor
air temperature
sensor is a 10 to 20 mA device
used to
measure
the outdoor-air
temperature.
The outdoor-air
temperature
is used to determine
when the EconoMi$er
IV can be used for free
cooling.
The sensor is factory-installed
on the EconoMi$er
IV in
the
outdoor
airstream.
(See
Fig.
20.)
The
operating
range
of
temperature
measurement
is 40 ° to 100°F.
Mixed
Air Temperature
(MAT) Sensor
The mixed
air temperature
sensor is a 3 K thermistor
located
at the
outlet
of the
indoor
fan. (See
Fig.
20.)
This
sensor
is factory
installed.
The operating
range of temperature
measurement
is 0 ° to
158°F.
The temperature
sensor is a short probe with blue wires running
to
it.
Outdoor
Air Lockout
Sensor
The
EconoMi$er
IV is equipped
with
an ambient
temperature
lockout
switch
located
in the outdoor
airstream
which
is used to
lock out the compressors
below a 42°F
ambient
temperature.
EconoMi$er
IV Controller
Wiring
and
Operational
Modes
Determine
the EconoMi$er
IV control
mode
before
set up of the
control.
Some modes
of operation
may require
different
sensors.
Refer to Table 17. The EconoMi$er
IV is supplied
from the factory
with a mixed
air temperature
sensor and an outdoor
air temperature
sensor.
This
allows
for
operation
of the EconoMi$er
IV with
outdoor
air dry bulb
changeover
control.
Additional
accessories
can be added to allow for different
types of changeover
control and
operation
of the EconoMi$er
IV and unit.
B
Internal
Wiring
Check all electrical connections in unit control boxes; tighten as
required.
27
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