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Table
9 - Belt Tension
Adjustment
BEN
TENSION
(Ib)
50PM
VOLTAGE
UnitModelNumberPositionl0
A,J
B,K
C,L
D,M
E,N
_P
G,Q
H,R
260
4.8
5.1
5.6
4.5
4.8
5.1
5.6
4.5
20
460
4.8
5.1
5.6
4.5
4.8
5.1
5.6
4.5
575
5.6
5.1
5.6
4.5
5.6
5.1
5.6
4.5
260
4.8
5.1
5.6
4.5
4.8
5.1
5.6
4.5
24
460
4.8
5.1
5.6
4.5
4.8
5.1
5.6
4.5
575
5.6
5.1
5.6
4.5
5.6
5.1
5.6
4.5
260
4.5
5.4
5.9
4.5
4.5
5.4
5.9
4.5
28
460
4.5
5.4
5.9
4.5
4.5
5.4
5.9
4.5
575
4.5
5.4
5.9
4.5
4.5
5.4
5.9
4.5
B
Table 10 - Sensor Temperature/Resistance
Values
TEMPERATURE
(F)
-58
-40
-22
-4
14
32
50
68
77
86
104
122
140
158
176
185
194
212
230
248
257
266
284
302
RESISTANCE
(ohms)
200,250
100,680
53,010
29,091
16,590
9,795
5,970
3,747
3,000
2,416
1,597
1,080
746
525
376
321
274
203
153
116
102
89
70
55
Evacuation
Proper evacuation
of the system
will remove
noncondensables
and
ensure
a tight, dry system
before
charging.
Evacuate
from
both
high
and low
side ports.
Never use the system
compressor
as a
vacuum
pump.
Refrigerant
tubes
and
indoor
coil
should
be
evacuated
to 500
microns.
Always
break
a vacuum
with
dry
nitrogen.
The two possible
methods
are the deep vacuum method
and the triple evacuation
method.
Deep Vacuum
Method
The deep
vacuum
method
requires
a vacuum
pump
capable
of
pulling
a minimum
vacuum
of 500 microns
and a vacuum
gauge
capable
of accurately
measuring
this
vacuum
depth.
The deep
vacuum
method
is the most
positive
way of assuring
a system
is
free of air and liquid water. (See Fig. 30.)
Triple Evacuation
Method
The triple evacuation
method
should
only be used when
vacuum
pump
is capable
of pumping
down
to 28-in.
of mercury
and
system
does not contain
any liquid water. Proceed
as follows:
1. Pump
system
down
to 28-in.
of mercury
and allow
pump
to continue
operating
for an additional
15 minutes.
2. Close service valves
and shut off vacuum
pump.
3. Connect
a nitrogen
cylinder
and regulator
to system
and
open until system pressure
is 2 psig.
4. Close
service
valve
and allow
system
to stand
for 1 hr.
During
this
time,
dry
nitrogen
will
be
able
to diffuse
throughout
the system,
absorbing
moisture.
5. Repeat
this procedure.
System
will then contain
minimal
amounts
of contaminants
and water vapor.
Refrigerant
Charge
Amount
of refrigerant
charge is listed on unit nameplate.
Refer to
Carrier
GTAC II; Module
5; Charging,
Recovery,
Recycling,
and
Reclamation
section
for charging
methods
and procedures.
Unit
panels
nmst
be in place when
unit is operating
during
charging
procedure.
Puron®
(R-410A)
refrigerant
cylinders
contain
a dip tube which
allows
liquid
refrigerant
to flow from
the cylinder
in an upright
position.
Charge
units with cylinder
in the upright
position
and a
commercial
type metering
device in the manifold
hose.
[]NIT
OPERATION
AND
SAFETY
HAZARD
Failure
to follow
this caution
may result in personal
iniury
or equipment
damage.
This unit uses Puron ® (R-410A)
refrigerant
system
which
operate
at higher pressures
than R-22 or other
systems.
No
other
refrigerant
may be used in this system.
Gauge
set,
hoses,
and recovery
system
nmst
be designed
to handle
Puron
refrigerant.
If unsure
about
equipment,
consult
the
equipment
manufacturer.
NOTE:
Do
not
use
recycled
refrigerant
as it may
contain
contaminants.
No Charge
Use
standard
evacuating
techniques.
After
evacuating
system,
weigh
in
the
specified
amount
of
refrigerant
(refer
to unit
nameplate).
Low Charge Cooling
Using
cooling
charging
chart (see Fig.
31-33),
add or remove
refrigerant
until
conditions
of the chart are met.
An accurate
pressure
gage
and
temperature-sensing
device
are required.
Charging
is accomplished
by ensuring
the proper
amount
of liquid
subcooling.
Measure
liquid
line pressure
at the liquid
line service
valve using pressure
gauge.
Connect
temperature
sensing
device to
the liquid
line near the liquid
line service
valve
and insulate
it so
that outdoor
ambient
temperature
does not affect reading.
To Use the
Cooling Charging
Chart
Use the above
temperature
and pressure
readings,
and find
the
intersection
point
on the cooling
charging
chart.
If intersection
point on chart is above line, add refrigerant.
If intersection
point on
chart is below
line, carefully
recover
some of the charge.
Recheck
suction
pressure
as charge is adjusted.
38
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