Product data

14
Unit selection
Select equipment to either match or be slightly less than
anticipated peak load. This provides better humidity
control, fewer unit cycles, and less part-load operation.
For units used in spaces with high sensible loads, base
equipment selection on unit sensible load, not on total
anticipated load. Adjust for anticipated room wet bulb
temperature to avoid undersizing equipment.
Unit mounting (outdoor)
Unit leveling — For reliable operation, units should be
level in all planes.
Clearance — Adequate clearance must be provided for
airflow. See dimensional drawings for proper clearances.
The condensing units are designed for free-blow applica-
tion. Air inlets and outlets should not be restricted.
Outdoor fan external static pressure available is less than
0.1 in. wg.
Unit location — Cooling units may be stacked 2 high.
Units may be wall mounted, pad mounted at ground level,
roof mounted, or mounted on or under a deck or patio. Be
sure water from roof does not drain directly onto the unit.
Unit mounting (indoor)
Clearance — Provide adequate clearance for airflow. The
unit return and discharge should not be obstructed by furni-
ture, curtains, or anything which may cause unit short
cycling or air recirculation. See base unit dimensional
drawings on pages 8-10 for required clearances.
Unit location — When selecting unit location, select a
location which will provide the best air circulation for the
room.
Units should be positioned as high as possible on the wall
for best air circulation. Allow adequate clearances above
the unit for servicing (removing unit covers). Place the unit
in the middle of the wall selected (if possible). Select an
outside wall if available to make piping easier, and place
the unit so it faces the normal location of room occupants.
Support
Adequate support must be provided to support the weight
of all fan coils. Refer to the Physical Data section on
page 6 for fan coil weights, and the base unit dimensional
drawings on pages 8-10 for the location of mounting
brackets.
System operating conditions
Operating limits:
OUTDOOR CONDENSING UNITS
FAN COIL UNITS
Low-ambient operation
Units can operate in cooling down to 55 F under all condi-
tions without a low-ambient kit.
Units equipped with accessory low-ambient kits should
also be equipped with an accessory crankcase heater.
Metering devices
Factory-installed capillary tubes are used as a metering
device.
Drain connections
Install drains to meet local sanitation codes. If adequate
gravity drainage cannot be provided, unit should be
equipped with accessory condensate pump. High wall fan
coil unit condensate pumps have an 6.5 ft suction lift.
See base unit dimensional drawings on pages 8-10 for
drain location and size.
Drain connections may be routed through alternate
locations. See base unit dimensional drawing on
pages 8-10 for possible alternate locations.
Refrigerant lines
General refrigerant line sizing:
1. All charges, line sizing, and capacities are based on
runs of 10 to 50 ft.
2. Refrigerant lines should not be buried in the ground. If
it is necessary to bury the lines, not more than 36 in.
should be buried. Provide a minimum 6-in. vertical rise
to the service valves to prevent refrigerant migration.
3. Both lines must be insulated. Use a minimum of
1
/
2
-in. thick insulation. Closed-cell insulation is
recommended in all long-line applications.
4. Special consideration should be given to isolating
interconnecting tubing from the building structure.
Isolate the tubing so that vibration or noise is not
transmitted into the structure.
5. Units are shipped with a full charge of R-22 refriger-
ant. Charge is based on 10 to 50 ft of line. Add addi-
tional charge by weight as necessary and check the
charge with a superheat calculator.
Long-line applications:
1. Mixed phase lines on all units should be
3
/
8
in. only.
DO NOT resize mixed phase lines for additional length.
2. Adjust charge to required amount by adding charge
and checking superheat.
For line lengths over 50 ft:
A crankcase heater should be added to the compressor.
Crankcase heaters help prevent refrigerant migration to
the compressor during the off cycle.
CONDITION
Maximum Cooling Ambient (F) 125
Minimum Cooling Ambient (F) (without
accessory low-ambient kit)
55
Minimum Cooling Ambient (F) (with
accessory low-ambient kit)
–20
Minimum Cooling Return-Air Temperature (F) 55
Maximum Cooling Return-Air Temperature (F) 95
Saturated Suction Temperature Range
Minimum (F)
Maximum (F)
–15
55
Saturated Condensing Temperature Range
Minimum (F)
Maximum (F)
80
150
Maximum Compressor Discharge Temperature (F) 275
Minimum Discharge Superheat (F) 60
CONDITION
Maximum Room
Temperature (F)
84
Minimum Room
Temperature (F)
64
Maximum Return Air (F)
Dry-Bulb
Wet-Bulb
85
72
Maximum Saturated
Suction Temperature (F)
55
Minimum Saturated
Suction Temperature (F)
27
Application data