Carrier 50TCQD17-D24, Инструкции по обслуживанию и техническому обслуживанию, Страница: 13 / 60

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How To Use Cooling Charging Charts:
Take the outdoor ambient temperature and read the
suction pressure gauge. Refer to chart to determine what
suction temperature should be. If suction temperature is
high, add refrigerant. If suction temperature is low,
carefully recover some of the charge. Recheck the suction
pressure as charge is adjusted.
SIZE DESIGNATION
NOMINAL TONS
REFERENCE
D17 15
D24 20
EXAMPLE:
Model 50TCQ*D17
Outdoor Temperature 85
_
F (29
_
C) . . . . . . . . . . . . . . . . . .
Suction Pressure 140 psig (965 kPa) . . . . . . . . . . . . . . . . .
Suction Temperature 55
_
F (13
_
C) . . . . . . . . . . . . . . . . . .
Refer to Fig. 21 through Fig. 24 for Cooling Charging
Charts.
Compressors
Lubrication:
Compressors are charged with the correct amount of oil at
the factory.
UNIT DAMAGE HAZARD
Failure to follow this caution can result in damage to
components.
The compressor is in a Puron (R--410A) refrigerant
system and uses a polyolester (POE) oil. This oil is
extremely hygroscopic, meaning it absorbs water
readily. POE oils can absorb 15 times as much water
as other oils designed for HCFC and CFC refrigerants.
Avoid exposure of POE oil to the atmosphere. This
exposure to the atmosphere can cause contaminants
that are harmful to R--410A components to form.
Keep POE oil containers closed until ready for use.
CAUTION
PURON
R
(R--410A) REFRIGERANT
This unit is designed for use with Puron (R--410A)
refrigerant. Do not use any other refrigerant in this
system.
Puron (R--410A) refrigerant is provided in pink (rose)
colored cylinders. These cylinders are available with and
without dip tubes; cylinders with dip tubes will have a
label indicating this feature. For a cylinder with a dip
tube, place the cylinder in the upright position (access
valve at the top) when removing liquid refrigerant for
charging. For a cylinder without a dip tube, invert the
cylinder (access valve on the bottom) when removing
liquid refrigerant.
Because Puron (R--410A) refrigerant is a blend, it is
strongly recommended that refrigerant always be removed
from the cylinder as a liquid. Add liquid refrigerant into
the system in the discharge line. If adding refrigerant into
the suction line, use a commercial metering/expansion
device at the gauge manifold; remove liquid from the
cylinder, pass it through the metering device at the gauge
set and then pass it into the suction line as a vapor. Do not
remove Puron (R--410A) refrigerant from the cylinder as a
vapor.
Refrigerant Charge
The amount of refrigerant charge is listed on the unit’s
nameplate. Refer to Carrier Publication, “GTAC2--5
Charging, Recovery, Recycling and Reclamation Training
Manual” and the following procedures:
Unit panels must be in place when unit is operating during
the charging procedure. If unit is equipped with a head
pressure control device, bypass it to ensure full fan
operation during charging.
NOTE
: Charge checking and adjustments must be made
while the system is operating in Cooling only.
No Charge:
Use standard evacuation techniques for Puron (R--410A)
refrigerant.. After evacuating system, weigh the specified
amount of refrigerant.
Low--Charge Cooling:
Using Cooling Charging Charts, Fig. 21 through Fig. 24,
vary refrigerant until the conditions of the appropriate
chart are met. Note the charging charts are different from
type normally used. Charts are based on charging the units
to the correct superheat for the various operating
conditions. An accurate pressure gauge and temperature
sensing device are required. Connect the pressure gauge to
the service port on the suction line. Mount the temperature
sensing device on the suction line and insulate it so that
outdoor ambient temperature does not affect the reading.
Indoor--air cfm must be within the normal operating range
of the unit.