EVACUATION
It will be necessary to evacuate the system if the unit has
developed a leak during shipment or was, for any other reason,
opened to the atmosphere. If a leak is suspected, leak test to
locate the leak. Repair the leak and test again.
WARNING: Never attempt to repair any brazed connections
while the system is under pressure. Personal injury
could result.
To verify if the system has no leaks, simply close the valve to
the vacuum pump suction to isolate the pump and hold the
system under vacuum. Watch the micron guage for a few
minutes. If the micron gauge indicates a steady and continuous
rise, it’s an indication of a leak. If the gauge shows a rise, then
levels off after a few minutes and remains fairly constant, its an
indication that the system is leak free but still contains moisture
and may require further evacation if the reading is above 500
microns.
SYSTEM CHARGE
The factory charge in the outdoor unit is listed in Table 3 and
includes enough charge for the unit and matched indoor coils.
Sweat connect units also include sufficient charge for 15 feet
of lines. Pre-charged line lengths are factory charged with the
correct amount of refrigerant required.
Sweat connect installations over 15 feet long and some indoor
coil matches may require some additional charge. Table 4 lists
the amount of any additional refrigerant required for line lengths
over 15 feet.
The “TOTAL SYSTEM CHARGE” must be permanently
stamped on the unit data plate.
Total system charge is determined as follows:
1. Determine the outdoor unit charge from Table 3.
2. Determine indoor coil adjustment from Table 3.
3. Calculate the line charge with the factors in Table 4.
a) Calculate total length of pre-charged lines for quick
connect units.
b) Calculate over 15 feet of sweat lines for sweat connect
units.
NOTE: The charge for pre-charged lines should be included
in the system charge shown on the data plate but need
not be added to the system. If sweat connect lines are
used, the line charge over 15 feet should be included
on the data plate and must be added to the system.
4. Total system charge = item 1 + item 2 + item 3.
5. Permanently stamp the unit data plate with the total amount
of refrigerant in the system.
Use the following charging method whenever additional refrig-
erant is required for the system charge.
CAUTION: Refrigerant charging should only be carried out by
a qualified air conditioning contractor.
Measurement Method
A calibrated charging cylinder or accurate weighing device
must be used to add refrigerant.
Check flare caps on service ports to be sure they are leak tight.
DO NOT OVERTIGHTEN (between 40 and 60 inch-lbs. maxi-
mum).
OWNER’S INSTRUCTION
Assist owner with processing warranty cards. Review User’s
Information Manual and provide a copy for the owner guidance
on proper operation and maintenance. Instruct the owner or the
operator how to start, stop and adjust temperature setting. The
owner should also be instructed about the 5 minute off cycle
timer and the defrost operation.
When applicable, instruct the owner that the compressor is
equipped with a crankcase heater to prevent the migration of
refrigerant to the compressor during the “OFF” cycle. The
heater is energized only when the unit is not running. If the main
switch is disconnected for long periods of shut down, do not
attempt to start the unit for 8 hours after the switch has been
connected. This will allow sufficient time for all liquid refrigerant
to be driven out of the compressor.
The installer should also instruct the owner on proper operation
and maintenance of all other system components.
LIQUID OD
VAPOR OD
R-22 CHARGE
OZ./FT.
5
⁄
16
“
5
⁄
8
”
0.44
5
⁄
16
“
3
⁄
4
”
0.46
5
⁄
16
“
7
⁄
8
”
0.48
TABLE 4 - REFRIGERANT LINE CHARGES
515.26-N1Y
Central Environmental Systems
9
