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7 SERIES 700A11 INSTALLATION MANUAL
Lockout
– when locked out, the blower will operate
continuously in “G” blower speed setting. The Alarm output
(ALM) and Lockout output (L) will be turned on. The fault
type identification display LED1 (Red) shall flash the fault
code. To reset lockout conditions with SW2-8 On, the demand
call must be removed for at least 30 seconds. To reset lockout
conditions with SW2-8 Off, the demand call must be removed
for at least 30 seconds. Lockout may also be reset by
turning power off for at least 30 seconds or by enabling the
emergency shutdown input for at least 30 seconds.
Lockout With Emergency Heat
- if the control is locked
out in the heating mode, and a call for emergency heat
is received, the control will operate in the emergency
heat mode while the compressor is locked out. The first
emergency heat output will be energized 10 seconds after
the W input is received, and the blower will shift to high
speed. If the control remains locked out, and the W input
is present, additional stage of emergency heat will stage
on after 2 minutes. When the W input is removed, all of
the emergency heat outputs will turn off, and the variable
speed ECM blower will shift to low speed.
High Pressure
– fault is recognized when the Normally
Closed High Pressure Switch, P4-9/10 opens, no matter how
momentarily. The High Pressure Switch is electrically in series
with the Compressor Contactor and serves as a hardwired
limit switch if an overpressure condition should occur.
Low Pressure
- fault is recognized when the Normally
Closed Low Pressure Switch, P4-7/8 is continuously open
for 30 seconds. Closure of the LPS any time during the 30
second recognition time restarts the 30 second continuous
open requirement. A continuously open LPS shall not be
recognized during the 2 minute startup bypass time.
Loss of Charge
– fault is recognized when the Normally
Closed Low Pressure Switch, P4-7/8 is open prior to the
compressor starting.
Condensate Overflow
- fault is recognized when the
impedance between this line and 24 VAC common or chassis
ground drops below 100K ohms for 30 seconds continuously.
Freeze Detection-Coax
- set points shall be either 30°F
or 15°F. When the thermistor temperature drops below
the selected set point, the control shall begin counting
down the 30 seconds delay. If the thermistor value rises
above the selected set point, then the count should reset.
The resistance value must remain below the selected set
point for the entire length of the appropriate delay to be
recognized as a fault. This fault will be ignored for the initial
2 minutes of the compressor run time.
Freeze Detection-Air Coil
- Air Coil Freeze Detection will
use the FP2 input to protect against ice formation on the
air coil. The FP2 input will operate exactly like FP1 except
that the set point is 30 degrees and is not field adjustable.
Over/Under Voltage Shutdown
- An over/under voltage
condition exists when the control voltage is outside the
range of 18 VAC to 30 VAC. If the over/under voltage
shutdown lasts for 15 minutes, the lockout and alarm relay
will be energized. Over/under voltage shutdown is self-
resetting in that if the voltage comes back within range
of 18 VAC to 30 VAC for at least 0.5 seconds, then normal
operation is restored.
Other Lockouts and Alarms
Several other lockouts and alarms are shown in the Status
LED1 (LED1, Red) table with the associated codes visible on
the thermostat, ABC Fault LED, and in text in the AID Tool.
Operation Description
Power Up
- The unit will not operate until all the inputs and
safety controls are checked for normal conditions. The unit
has a 5 to 80 second random start delay at power up. Then
the compressor has a 4 minute anti-short cycle delay after
the random start delay.
Standby
- In standby mode the compressor, pump, and
blower motor are not active. The RV may be active. The
blower and compressor will be off.
Heating Operation
- The unit will operate based upon demand
as calculated by the room setpoint algorithm. The resulting
compressor speed (1-12) will also select an appropriate blower
speed for the selected compressor speed. Aux Heat will not be
available (on IntelliZone2 Aux Heat is available on compressor
speeds 10-12) until after the 12th compressor speed has been
operational and still is not satisfying the thermostat, then
auxiliary electric heat will be activated.
Emergency Heat (W)
- The blower will be started on G
speed, 10 seconds later the first stage of electric heat will
be turned on. 5 seconds after the first stage of electric
heat is energized the blower will shift to Aux speed. If the
emergency heat demand is not satisfied after 2 minutes the
second electric heat stage will be energized.
Cooling Operation
- The unit will operate based upon
demand as calculated by the room setpoint algorithm.
The resulting compressor speed, speeds 1-9, (speeds 10-12
are reserved for SuperBoost mode only) will also select
CAUTION: Frequent cycling of power to the drive
can damage the drive! Wait at least 5 minutes
between cycles (connecting and disconnecting
power to the drive).
The Aurora Advanced VS Control System cont.
