York YBS006-070 Installation Manual page 33

Lx compact commercial geothermal/ water source heat pumps single capacity
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Controls - Aurora Base Control cont.
Cycle with Blower - The accessory relay will cycle with the
blower output.
Cycle with Compressor - The accessory relay will cycle with
the compressor output.
Water Valve Slow Opening - The accessory relay will cycle and
delay both the blower and compressor output for 90 seconds.
SW2-6
CC Operation – selection of single or dual capacity
compressor. On = Single Stage; Off = Dual Capacity
SW2-7
Lockout and Alarm Outputs (P2) – selection of a
continuous or pulsed output for both the LO and ALM
Outputs. On = Continuous; Off = Pulsed
SW2-8
Future Use
Alarm Jumper Clip Selection
From the factory, ALM is connected to 24 VAC via JW2. By cutting
JW2, ALM becomes a dry contact connected to ALG.
ECM Blower Speeds
The blower speeds can be changed either by using the ECM
manual configurations mode method or by using the Aurora
AID Tool directly (see Instruction Guide: Aurora Interface and
Diagnostics (AID) Tool topic).
Field Selectable Options via Software
(Selectable via the Aurora AID Tool)
ECM Blower Speeds
An ECM blower motor can be driven directly using the onboard
PWM output. Four blower speeds are available, based upon the "G",
Y1 (low), Y2 (high), and Aux input signals to the board. The blower
speeds can be changed either by the ECM manual configurations
mode method (see ECM Configuration Mode topic) or by using the
Aurora AID Tool directly. All four blower speeds can be set to the
same speed if desired. Aux blower speed will remain at default or
current setting and requires the AID Tool for adjustment.
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.
LX COMPACT SERIES INSTALLATION MANUAL
Lockout – when locked out, the blower will operate continuously in
"G" speed, and PSC blower motor output will remain on. 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 a Y2 or 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 will turn off, and
the ECM blower will shift to "G" speed and PSC blower motor output
will remain on.
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.
Freeze Detection (Air Coil) - uses 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.
33

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