Wear safety glasses and gloves when handling refrigerants.
Keep torches and other ignition sources away from refriger-
ants and oils. Failure to follow this warning can cause a fire,
serious injury, or death.
The scroll compressor pumps refrigerant throughout the system by
the interaction of a stationary and an orbiting scroll. The scroll
compressor has no dynamic suction or discharge valves, and it is
more tolerant of stresses caused by debris, liquid slugging, and
flooded starts. The pressure relief port is a safety device, designed
to protect against extreme high pressure. The relief port has an
operating range between 550 (3792) and 625 psi (4309 kpa)
differential pressure.
The information below covers the refrigerant system of the 50JZ,
including the compressor oil needed, servicing systems on roofs
containing synthetic materials, the filter drier and refrigerant
charging.
The Copeland scroll compressor uses Mobil 3MA POE oil.
This is the only oil allowed for oil recharge.
Refrigerant
This system uses Puron (R-410A) refrigerant which has
higher operating pressures than R-22 and other refrigerants.
No other refrigerant may be used in this system. Gauge set,
hoses, and recovery system must be designed to handle
Puron. If you are unsure consult the equipment manufacturer.
Failure to use Puron compatible servicing equipment or
replacement components may result in property damage or
injury.
Compressor Oil
The compressor in this system uses a polyolester (POE) oil, Mobil
3MA POE. 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. Take all necessary
precautions to avoid exposure of the oil to the atmosphere.
Servicing Systems on Roofs with Synthetic Materials
POE (polyolester) compressor lubricants are known to cause long
term damage to some synthetic roofing materials.
Exposure, even if immediately cleaned up, may cause embrittle-
ment (leading to cracking) to occur in one year or more. When
performing any service that may risk exposure of compressor oil to
the roof, take appropriate precautions to protect roofing. Proce-
dures which risk oil leakage include, but are not limited to,
compressor replacement, repairing refrigerant leaks, replacing
refrigerant components such as filter drier, pressure switch, me-
tering device, coil, accumulator, or reversing valve.
Synthetic Roof Precautionary Procedure
1. Cover extended roof working area with an impermeable
polyethylene (plastic) drip cloth or tarp. Cover an approximate
10 x 10 ft. (3 x 3 m) area.
2. Cover area in front of the unit service panel with a terry cloth
shop towel to absorb lubricant spills and prevent run-offs, and
protect drop cloth from tears caused by tools or components.
3. Place terry cloth shop towel inside unit immediately under
component(s) to be serviced and prevent lubricant run-offs
through the louvered openings in the unit base.
4. Perform required service.
5. Remove and dispose of any oil contaminated material per
local codes.
Liquid Line Filter Drier
The biflow filter drier is specifically designed to operate with
Puron. Use only factory-authorized replacement components. Fil-
ter drier must be replaced whenever the refrigerant system is
opened. When removing a filter drier, use a tubing cutter to cut the
drier from the system.
Do not unsweat a filter drier from the
system.
Heat from unsweating will release moisture and contami-
nants from drier into system.
Puron (R-410A) Refrigerant Charging
Refer to unit information plate and charging chart.
Some R-410A
refrigerant cylinders contain a dip tube to allow liquid refrig-
erant to flow from cylinder in upright position.
For cylinders
equipped with a dip tube, charge Puron units with cylinder in
upright position and a commercial metering device in manifold
hose. Charge refrigerant into suction-line.
Refrigeration Service Ports
Each unit system has 3 Schrader-type service ports: one on the
suction line, one on the liquid line, and one on the compressor
discharge line. Be sure that caps on the ports are tight.
High Flow Valves
Located on the compressor hot gas and suction tubes are High
Flow Valves. Large black plastic caps distinguish these valves
with o-rings located inside the caps. These valves cannot be
accessed for service in the field. Ensure the plastic caps are in
place and tight or the possibility of leakage could occur.
Step 9—System Information
PHASE MONITOR CONTROL
1. 3–phase scroll compressors are rotational sensitive
2. A flashing LED on phase monitor indicates reverse rotation.
3. This will not allow contactor to be energized
4. Disconnect power to unit and interchange 2 field wiring leads
on unit contactor.
Follow these steps to properly start up the system:
1. Fully back seat (open) liquid and vapor-tube service valves.
2. Unit is shipped with valve stem(s) front seated (closed) and
caps installed. Replace stem caps after system is opened to
refridgerant flow. Replace caps finger-tight and tighten with
wrench an additional 1/12 turn for back-seating valves (male
square stem).
3. Close electrical disconnects to energize system.
4. Set room thermostat desired temperature. Be sure set point is
below indoor ambient temperature.
5. Set room thermostat to COOL and fan control to ON or AUTO
mode, as desired. Operate unit for 15 minutes. Check system
refridgerant charge.
SEQUENCE OF OPERATION
Turn on power to indoor and outdoor unit. Transformer is
energized.
On a call for cooling, thermostat make circuits R-Y and R-G. On
three phase models with scroll compressors, the units are equipped
with a phase monitor to detect if the incoming power is correctly
phased for compressor operation. If the phasing is correct, circuit
R-Y energizes contactor, starting outdoor fan motor and compres-
sor circuit. R-G energizes indoor unit blower relay, starting indoor
blower motor on high speed.
NOTE:
If the phasing is incorrect, the contactor will not be
energized. To correct the phasing, interchange any two of the three
power connections on the field side.
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