National Comfort Product 1000 SERIES, Руководство по установке

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1.
1. Connect the vacuum pump to the service ports of the liquid
line and the vapor line service valves. If the vacuum pump
lines do not contain shut-off valves, hook up the vacuum
pump through a manifold gauge set, as the vacuum pump
lines must be closed for step 4 below.
a. If the evacuation is being performed on a new system
installation, the condensing unit service valves should
be kept in the closed position. The vacuum pump will
then be able to evacuate the refrigerant lines and
evaporator coil.
b. If the evacuation is being performed on an installation
where the condensing unit factory charge has been
lost, the service valves should be opened.
2. Following the vacuum pump manufacturer’s instructions,
allow the pump to operate until the system has been evacu-
ated down to 300 microns.
NOTE: Check for leaks if unable to get to 300 microns.
3. Allow the pump to continue running an additional 15 min-
utes. Turn off the pump and leave connections secured. Af-
ter 10 minutes if system fails to hold 500 microns or less,
check all connections for tight fit and repeat evacuation
procedure.
4. Isolate the vacuum pump by closing the shut-off valves on
vacuum pump lines or test gauge manifold.
5. Open the service valves. Opening the service valves will
allow the refrigerant in the condensing unit to enter the re-
frigerant lines and evaporator coil. The vacuum pump can
now be disconnected.
The condensing unit comes from the factory pre-charged for the
condensing unit, recommended evaporator coil, and the 10 feet
of refrigerant lines. If the actual line length is greater or less then
10 feet, add or remove refrigerant at the rate of 0.7 ounces per
foot.
If the condensing unit charge was lost for any reason, add fac-
tory refrigerant charge listed on condensing unit data plate, plus
adjustments described above.
If the unit is operating during charge adjustment, the access
panel must be in place to prevent high head pressure which
would shut down the unit.
Step 4 - Evacuation
Step 5 - Refrigerant Charging
1. Connect the charging cylinder to the manifold gauge set.
Open the charging cylinder valve and bleed air out of the
charging hose at the manifold gauge set connection.
2. Tighten the manifold gauge set charging connection. Open
the main manifold gauge set valve and introduce refrigerant
into the system.
NOTE:
Oil charge is polyester 32bce.
3. When the correct refrigerant charge level is obtained,
remove the manifold gauge set.
4. Replace the gauge port caps.
Permanently stamp the unit data plate with the total amount
of refrigerant in the system.
For coils equipped with TXV’s charge to sub-cooling, 15 - 19° at
service valve; superheat, 8 - 12° at service valve
Notes:
All information based on 400 CFM/Ton.
Recommended superheat is 8 - 12° at service valve.
Superheat temperature measurements should be taken within 3 feet
of the compressor suction line connection.
*** When checking superheat at extreme high temperature, charge to
minimum of 5° of super heat and re-check when temperature falls
back into the norm.
NOTE: Make certain that the volts, hertz, and phase cor-
respond to that specified on the unit rating plate, and
that the service provided by the utility is sufficient to
handle the additional load imposed by this equipment.
Make all electrical connections in accordance with the National
Electrical Code and any pertinent local codes or ordinances.
Use a separate branch electrical circuit for this unit. Locate a
disconnecting means within sight of and readily accessible to
the unit.
A. Line Voltage Connections
a. Connect the single phase power supply to unit contactor
terminal L1 and L2
b. Connect ground wire to lug
B. Low Voltage Connections
Consult the indoor unit installation instructions for thermostat
connections. Use a 2-wire thermostat cable between the out-
door and indoor units.
The system should be liquid-charged through the liquid-receiver
shut-off valve or through a valve in the liquid line. The use of a filter
drier in the charging line is highly recommended. Because R410A
and R407C are blends and scrolls have discharge check valves,
systems should be liquid-charged on both the high and low sides
simultaneously to ensure a positive refrigerant pressure is present
in the compressor before it runs. The majority of the charge should
be placed in the high side of the system to prevent bearing washout
during first-time start on the assembly line.
CAUTION
Low Suction Pressure Operation!
Compressor Damage!
Do not operate with a restricted suction. Do not operate with the
low-pressure cut-out bridged. Do not operate compressor without
enough system charge to maintain at least 0.5 bar suction pressure.
Allowing pressure to drop below 0.5 bar for more than a few seconds
may overheat scrolls and cause early drive bearing damage.
Step 6 - Electrical Connections
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