WaterFurnace Envision2 - Manual (Page 30)

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ENVISION 2 COMPACT INSTALLATION MANUAL
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.
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.
Controls - Aurora Base Control cont.