National Comfort Products MADISON 1000 SERIES, Installation Instructions Manual

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1.
Connect the vacuum pump to the service ports of the liquid 1.
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.
Following the vacuum pump manufacturer’s instructions, 2.
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.
Allow the pump to continue running an additional 15 min - 3.
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.
Isolate the vacuum pump by closing the shut-off valves on 4.
vacuum pump lines or test gauge manifold.
Open the service valves. Opening the service valves will 5.
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.
Connect the charging cylinder to the manifold gauge set. 1.
Open the charging cylinder valve and bleed air out of the
charging hose at the manifold gauge set connection.
Tighten the manifold gauge set charging connection. Open 2.
the main manifold gauge set valve and introduce refrigerant
into the system.
NOTE: Oil charge is polyester 32bce.
Step 4 - Evacuation
Step 5 - Refrigerant Charging
When the correct refrigerant charge level is obtained, re - 3.
move the manifold gauge set.
Replace the gauge port caps. 4.
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, 12 - 16° at ser -
vice 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 ( see Figure 2 )
a. Connect the single phase power supply to unit contactor
terminal L1 and L2
b. Connect ground wire to lug
B. Low Voltage Connections ( see Figure 3 )
Consult the indoor unit installation instructions for thermostat
connections. Use a 2-wire thermostat cable between the out -
door and indoor units.
When locating the room thermostat, it should be in the natural
circulating path of room air. Avoid locations where the thermo -
stat would be exposed to cold air infiltration; drafts from win -
dows, doors or other openings leading to the outside; exposure
to air currents from warm-or-cold air registers or to exposure
where the natural circulation of the air is cut off, such as behind
doors, above or below mantels, shelves, etc.
On a “call for cooling”, the thermostat “makes” circuits R-Y and
R-G. Circuit R-Y energizes the contactor starting the outdoor
fan motor and compressor circuit. R-G energizes the indoor unit
blower relay starting the indoor blower motor.
When the thermostat is satisfied, its contacts open, de-ener -
gizing the contactor and blower relay. Compressor and motors
should stop.
Step 6 - Electrical Connections
Sequence of Operations
4