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existing thermostat and liquid solenoid valve. When found,
convert the evaporator second stage solenoid control into a
drop-solenoid control. Use the two SVR relays and transformer
as required on 569J***T/U models (above); wire the SVRs and
transformer per two solenoid valve systems.
SELECTING AN ACCUMULATOR
Because all 569J models use scroll compressors, an accumulator
is not required. If an accumulator is to be added, check the accu-
mulator manufacturer's literature carefully for indication of its
suitability for use with R-410A; look for minimum working
pressure of 200 psig (1380 kPa). Select the accumulator first on
the basis of its cataloged minimum capacity (tons) to ensure oil re-
turn from the accumulator, then on tube size or holding capacity.
MAKE PIPING CONNECTIONS
Piping connections at the 569J unit are ball valves with stub
tube extensions. Do not open the unit service valves until all
interconnecting tube brazing has been completed. The stub
tube connections include 1/4-in. SAE service fittings with
Schrader valve cores (see Fig. 12). Before making any brazed
connections to the unit service valves, remove both Schrader
valve caps and cores and save for re-installation. Connect a
source for nitrogen to one of these service fittings during tube
brazing to prevent the formation of copper oxides inside the
tubes at brazed joints.
When connecting the field tubing to the 569J service valves,
wrap the valves in wet rags to prevent overheating.
Pressure-test all joints from outdoor unit connections over to
the evaporator coil, using nitrogen as pressure and with soap-
and-bubbles.
When pressure-testing is completed, remove the nitrogen
source at the outdoor unit service valves and re-install the two
Schrader valve cores. Torque the cores to 2 to 3 in.-lb (23 to
34 N-cm).
Factory
High-Flow
Access Port
Service Valve
with Stem Cap
Fig. 12 — Typical Piping Connection Assembly
EVACUATION/DEHYDRATION
Evacuate and dehydrate the connected refrigeration system(s)
(excluding the 569J unit) to 500 microns using a two-stage
vacuum pump attached to the service ports outside the 569J
service valves, following description in GTAC II, Module 4,
System Dehydration.
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal injury,
death and/or equipment damage.
R-410A refrigerant systems operate at higher pressures
than standard R-22 systems. Do not use R-22 service
equipment
or
components
equipment.
Field Service
Access Port
(Schrader core)
Sweat
Connection
on
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, in-
vert the cylinder (access valve on the bottom) when removing
liquid refrigerant.
Because Puron (R-410A) refrigerant is a blend, it is strongly rec-
ommended 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.
PRELIMINARY CHARGE
Before starting the unit, charge R-410A liquid refrigerant into
the high side of each 569J circuit through the liquid service
valve(s). The amount of refrigerant added must be at least 80%
of the operating charge listed in Tables 4 or 5 for LINEAR line
length LESS the factory charge quantity (if factory shipping
charge has not been removed). See example below.
NOTE: See "Adjust Refrigerant Charge" on page 21 for details on
refrigerant charge adjustment. Be sure that all condenser fans are
operating while charging the unit.
Allow high and low side pressures to equalize. If pressures do
not equalize readily, charge R-410A vapor (using special ser-
vice manifold with expansion device) into the suction line ser-
vice port for the low side of system to assure charge in the
evaporator. Refer to GTAC II, Module 5, Charging, Recover,
Recycling, and Reclamation for liquid charging procedures.
Example:
569J*25A/B
60-ft (18.3 m) linear line length
Equivalent line length 90-ft (27.4 m)
Liquid Lift: 20-ft (6.1 m)
Select line sizes from Table 8 (569J***T/U):
Liquid 1/2 in.
Suction 1-1/8 in.
Charge
Circuit 1: 23.1 lb (at 75-ft linear length)
Circuit 2: 22.0 lb
80% of Operating Charge:
Circuit 1: 0.80 x 23.0 = 18.4 lb
Circuit 2: 0.80 x 22.0 = 17.6 lb
Factory Shipping Charge: 15 lb
Field-Charge
Circuit 1: 18.4 - 15.0 = 3.4 lb
Circuit 2: 17.6 - 15.0 = 2.6 lb
For linear line lengths longer than 125 ft (38 m), contact your
local Bryant representative for system charge value.
Step 7 — Install Accessories
Accessories requiring modifications to unit wiring should be
completed now. These accessories may include Winter Start
controls and Low Ambient controls. Refer to the instructions
shipped with the accessory.
14
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