Specifications

APPLICATION DATA
1. Unit selection
Select equipment to either match or be slightly less than
anticipated peak cooling load. This provides better humidity
control, fewer unit cycles, and less part-load operation.
Heating and cooling design loads must both be checked. To
meet heating requirements, calculate heater in addition to
heat pump capacity. Since indoor unit is off during defrost
cycles, it is not necessary for electric heater to meet total
heating requirement.
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 tem-
perature to avoid undersizing equipment.
Heating load using outdoor air must be checked in addition
to cooling load. Heating load of outdoor air can greatly
reduce heating capability.
When selecting equipment which has outdoor air intro-
duced into the unit, determine the mix conditions of room air
and outdoor air at design conditions. The cooling capacity
tables in this literature are based on 80 F edb. Adjust for
actual dry-bulb and wet-bulb conditions with the required
outdoor air to select the proper equipment.
2. Unit combinations and coil mixed matches
The 538D and 538B units are the only units approved for
use with the 619C,F, and E, duct-free split systems. The
538B units may also be used with other fan coil units (in
approved combinations).
NOTE: The 619C, F fan coils may also be used with 538A
condensing units to provide systems with cooling and elec-
tric heat. Refer to cooling system product data literature for
more details.
3. Unit mounting (outdoor)
a. Unit leveling — For reliable operation, units should be
level in all planes.
b. Clearance — Adequate clearance must be provided for
airflow. See dimensional drawings for proper clear-
ances. The heat pump units are designed for free-blow
application. Air inlets and outlets should not be re-
stricted. Outdoor fan external static pressure available is
less than 0.1 in. wg.
c. Unit location — Heat pump units should not be
stacked. Defrosted condensate from upper unit will
refreeze on lower unit. Units may be wall mounted, pad
mounted at ground level, roof mounted, or mounted on
or under a deck. Be sure water drainage from roof will
not drain directly onto the unit.
Units must be mounted so that snow will not obstruct air-
flow and so that defrosting coil ice can drain freely from
the outdoor unit drain pan. Snow and ice stands can be
field-fabricated to raise 538B and 538D (snow stand
only) size 018 or larger units to meet these conditions if
necessary. Contact your representative for drawings.
If 538B or 538D018,024 outdoor heat pump units are be-
ing mounted near a wall, the air should discharge toward
the wall. This will provide inherent coil protection and
the best possible sound and airflow performance. The
538D009,012 units should be mounted with fan dis-
charge pointing away from the wall.
4. Unit mounting (indoor)
a. Unit leveling — For reliable operation, units should
be level in all planes. The 619C ceiling-suspended fan
coils may have a slight pitch, but only toward the drain
connection.
b. Clearance — Provide adequate clearance for air-
flow. The unit return and discharge should not be ob-
structed by furniture, curtains, or anything which may
cause unit short cycling or air recirculation. See base
unit dimensional drawings on pages 18-24 for required
clearances.
c. Unit location — When selecting unit location, select a
location which will provide the best air circulation for the
room.
1) 619E HIGH WALL UNITS — These 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.
2) 619C CEILING-SUSPENDED UNITS — These units
should be mounted near the ceiling and against a
wall. The unit should be centered in the room for best
performance. Locating the unit on an outside wall will
make piping easier, but units may also be mounted
away from a wall if desired. (If the unit is mounted
away from a wall, the rear panel of the unit may need
a field-supplied trim strip for improved appearance.)
For quietest operation, locate the fan coil return over
an area which is not normally occupied. Do not block
air discharge for a minimum of 15 ft to prevent dump-
ing of cold air and drafts.
3) 619F IN-CEILING CASSETTE UNITS — These units
should be mounted in the ceiling, preferably near the
center of the room. If the unit must be mounted near
a wall, close the air discharge on the blocked side(s).
(Up to 2 sides may be blocked.) Locate the control
box away from the blocked side(s).
5. Mounting template
The 619C fan coil units are furnished with a mounting tem-
plate to mark the location of the mounting brackets, wiring,
and refrigeration hole locations. In addition, the 619C units
indicate the location of ventilation-air connections.
6. Support
Adequate support must be provided to support the weight
of all fan coils. Refer to the Physical Data section on
pages 11-17 for fan coil weights, and the base unit dimen-
sional drawings on pages 18-24 for the location of mounting
brackets.
64