York LX series, Руководство по установке

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Field Selectable Options via Software
(Selectable via the Aurora AID Tool)
Safety Features
The following safety features are provided to protect the
compressor, heat exchangers, wiring and other components from
damage caused by operation outside of design conditions.
Fuse – a 3 amp automotive type plug-in fuse provides protection
against short circuit or overload conditions.
Anti-Short Cycle Protection – 4 minute anti-short cycle protection
for the compressor.
Random Start – 5 to 80 second random start upon power up.
Fault Retry – in the fault condition, the control will stage off the
outputs and then “try again” to satisfy the thermostat Y input
call. Once the thermostat input calls are satisfied, the control will
continue on as if no fault occurred. If 3 consecutive faults occur
without satisfying the thermostat Y input call, then the control will
go to Lockout mode.
Lockout – when locked out, the blower will operate continuously.
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, thermostat inputs
“Y1”, “Y2”, and “W” must be removed for at least 3 seconds. To reset
lockout conditions with SW2-8 Off, thermostat inputs “Y1”, “Y2”, “W”,
and “DH” must be removed for at least 3 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 3 seconds.
Lockout With Emergency Heat - if the control is locked out in the
heating mode and W input 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 and blower will turn off.
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 hard-wired 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.
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.
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, Y1, Y2, W, DH, and G are not active.
Input O may be active. The blower and compressor will be off.
Heating Operation
Heating, 1st Stage (Y1) - The blower is started on “Y1” speed
immediately and the compressor is energized 10 seconds after the
Y1 input is received.
Heating, 2nd Stage (Y1, Y2) - The compressor will be staged to
full capacity 20 seconds after Y2 input is received. The 5 speed
ECM blower will shift to Y2 speed immediately.
Heating, 3rd Stage (Y1, Y2, W) - The first stage of electric heat is
energized 10 seconds after the W command is received. Blower
will increase to "W' speed immediately. If the demand continues
the second stage of electric heat will be energized after 5 minutes.
The Aurora ‘Base’ Control System cont.
LX SERIES INSTALLATION MANUAL