Operating Mode Memory; Automatic Operation Auto. Mode; Operating Fault Diagnosis; Microprocessor Control Operation - Bryant 619E Installation, Start-Up And Service Instructions Manual

*Potential range.
†Desirable range.
NOTE: Unit is equipped with manual air vents which direct the air from
side to side. Up and down louver motion can be selected using the re-
mote controller. For maximum comfort, set louvers within the swing range.
See Adjusting Airflow section on page 13 for more information.
Fig. 19 — Louver Adjustments
VII. OPERATING MODE MEMORY
After the system is turned off or after a power failure, the
system remains in the last operating mode selected. When
the system is turned back on, or when power is automati-
cally restored, operation continues in the same operating mode
as when power shut down.
VIII. AUTOMATIC OPERATION AUTO. MODE
If Auto. mode is selected, the system automatically switches
the operating mode from heating (heat pump system only) to
cooling, or from cooling to heating (heat pump system only)
depending on the selected temperature.
NOTE: Between the cooling cycle and the heating cycle there
is a neutral zone of approximately 2° F above and 2° F be-
low the selected temperature when only the fan is operating.
IX. OPERATING FAULT DIAGNOSIS
The system includes an automatic diagnosis feature which is
activated under difficult or unacceptable operating condi-
tions. If such conditions occur, the system stops automati-
cally, the operating fault signal appears (green ''UNIT ON''
light on the front of the fan coil unit flashes), and an analysis
of the system operating conditions is initiated. The system
will then be restarted automatically, as soon as normal con-
ditions have been restored, or it will remain off. If the system
does not start again, the green ''UNIT ON'' light will flash an
error code.
X. MICROPROCESSOR CONTROL OPERATION
This system is controlled by a microprocessor designed to give
optimum levels of comfort and operating efficiency. The con-
trol is located in the 619E unit. To operate the unit, the factory-
supplied remote controller is required.
There are 9 (cooling only systems) or 12 (heat pump systems)
operating modes (including the Off mode) for the unit. Each
mode operates as follows:
• Off Mode — When the unit is in the Off mode, all func-
tions (compressor, outdoor fan, indoor fan, and air sweep)
are off, except the reversing valve (heat pump only), which
will stay energized if the unit was last operated in the Cool-
ing mode.
• Air Circulation Mode (Fan Operation Only) — When Air
Circulation mode is selected, the indoor fan will operate
continuously in the selected speed (high, medium, low, or
auto.). If the Auto. mode is selected, the indoor fan will op-
erate at low speed. The compressor and outdoor fan are
off. The reversing valve (heat pump only) will remain in
the last operating mode.
• Cooling Mode — When the Cooling mode is selected, the
indoor fan will operate continuously at the selected speed
if the speed is high, medium, or low. If the indoor fan is in
Auto. mode, the fan will change operating speeds depend-
ing on the difference between the room temperature and
the set point. The reversing valve (heat pump only) will be
energized. The compressor cannot run for 3 minutes from
the time the system starts up or for 3 minutes from the
time the compressor last operated. When the temperature
of the room is equal to or greater than the selected tem-
perature, the compressor and outdoor fan will operate un-
til the room temperature is 2° F below the set point, and
then shut off. When the room temperature is less than the
selected temperature, the compressor and outdoor fan re-
main off.
• Maximum Dehumidification Mode — When the Dehumidi-
fication mode is selected, the indoor fan will operate con-
tinuously at the selected speed if the speed is high, me-
dium, or low. If the indoor fan is in Auto. mode, the fan
will change operating speeds depending on the room tem-
perature. If the room temperature is below the set point,
the indoor fan will run at ultra-low speed, and the com-
pressor could run for up to 4 minutes. (Ultra-low speed is
a control-driven speed [not user configurable] used to sample
the space when the fan would normally be off.) The revers-
ing valve (heat pump only) will be energized. The compres-
sor cannot run for 3 minutes from the time the system starts
up or for 3 minutes from the time the compressor last
operated.
Initial Operation — When the mode is first selected, one of
the following occurs:
1. If the room temperature is above or equal to the se-
lected temperature, the unit will operate for 16 min-
utes, and the compressor and outdoor fan will operate.
The indoor fan will operate as in the Cooling mode. Af-
ter 16 minutes of operation (or when the room reaches
2° F below set point), the unit switches to normal dehu-
midification operation.
2. If the room temperature is below the selected tempera-
ture, the unit will operate for 8 minutes as follows: the
compressor and outdoor fan will operate for 3 minutes.
The indoor fan will operate in low speed, and 30 sec-
onds after the compressor stops, the indoor fan stops.
The unit remains off for 1 minute, and then the indoor
fan starts in ultra-low speed for 30 seconds. The unit
then switches to normal dehumidification operation.
Normal Operation — One of the following will take place:
1. When the temperature of the room is equal to or greater
than the selected temperature (by not more than 3° F),
the unit will operate for 8 minutes as follows: the com-
pressor and outdoor fan will operate for 3 minutes. The
indoor fan will operate in low speed, and 30 seconds af-
ter the compressor stops, the indoor fan stops. The unit
remains off for 1 minute, and then the indoor fan starts
in ultra-low speed for 30 seconds. The normal dehumidi-
fication operation is repeated for the newly sensed room
temperature.
2. If the room temperature is equal to or greater than
the selected temperature, but not by more than be-
tween 4° F and 6° F, the compressor and outdoor fan op-
erate for 4 minutes. The indoor fan will run at ultra-low
speed and will stop 30 seconds after the compressor stops.
After 3 minutes, the indoor fan runs at ultra-low speed
for 30 seconds. The normal dehumidification operation
is repeated for the newly sensed room temperature.
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