Bryant 548J - Manual (Page 13)

13
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. Admit 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
Amount of refrigerant charge is listed on the unit’s
nameplate. Refer to the 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.
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 in the
specified amount of refrigerant.
Low--Charge Cooling
Using Cooling Charging Charts, Fig. 20 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. 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.
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
04A 3
05A 4
06A 5
07A 6
08D 7.5
09D 8.5
EXAMPLE:
Model 548J*04A
Outdoor Temperature
85_F (29_C) . . . . . . . . . . . . . . . . . .
Suction Pressure 140 psig (965 kPa) . . . . . . . . . . . . . . . . .
Suction Temperature should be 55_F (13_C) . . . . . . . . . .
Compressors
Lubrication
Compressors are charged with the correct amount of oil at
the factory.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in damage to
components.
The compressor is in a PuronR 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 the oil to the atmosphere.
CAUTION
!
Replacing Compressor
The compressor used with Puron refrigerant contains a
POE oil. This oil has a high affinity for moisture. Do not
remove the compressor’s tube plugs until ready to insert
the unit suction and discharge tube ends.
Compressor mounting bolt torque is 65--75 in--lbs (7.3--8.5
Nm).
548J