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21
Heat Controller
VFH InverterFlex
®
- Outdoor Ductless Mini-Split
36KBTU/H
Unit performance, efficiency, and life depends, to
a large extent, on a proper system charge. Time
spent on getting the charge right at start-up will
payoff in the long run. Operating conditions such
as voltage, air flow, evaporator coil size, and indoor
and outdoor temperature and humidity all have
an effect on the system pressures and superheat
conditions.
Units are factory charged before shipment. See
rating plate on outdoor unit for exact amount.
These units should be critically charged to ensure
proper performance. Some systems may require
additional charging of refrigerant, depending on
line set lengths. If the total line set length is less
than the amount in the table below, no additional
Field Charging
KBTU/H
Total allowable length (for all indoor units)
18
32.8 ft. (10m)
24
98 ft. (30m)
30 / 36
131 ft. (40m)
42
166 ft. (50m)
42KBTU/H
Electrical Work
Fig. 19
refrigerant is needed.
If the total length or refrigerant lines for all models is
greater than the amount shown in the chart, additional
refrigerant is needed.
18 - 30 KBTU/H Units
Additional Refrigerant Charge = sum of additional line
length* ft (m) times 0.22 oz/ft (20g/m).
36 - 42 KBTU/H Systems
Additional Refrigerant Charge = sum of additional line
length* ft (m) times 0.24 oz/ft (22g/m).
*Additional line length is the sum of all the line sets
for all indoor units subtracted from the total allowable
length shown in the table.