Controls - aurora base control cont, Field selectable options via software, Safety features – WaterFurnace Envision2 User Manual
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ENVISION
2
COMPACT - 50 HZ INSTALLATION MANUAL
Access Relay Operation
SW2-4
SW2-5
Cycle with Blower
ON
ON
Cycle with Compressor
OFF
OFF
Water Valve Slow Opening
ON
OFF
(Reserved)
OFF
ON
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 Reheat Operation – On = Normal; Off = Reheat
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.
Variable Speed ECM Blower Speeds
The blower speeds can be changed either by using the
variable speed ECM manual configurations mode method
or by using the Aurora AID Tool directly (see Instruction
Guide: Aurora Interface and Diagnostic (AID) Tool topic).
Field Selectable Options via Software
(Selectable via the Aurora AID Tool)
Variable Speed ECM Blower Speeds
A traditional variable speed ECM blower motor can be
driven directly using the onboard PWM output. Three
blower speeds are available, based upon the G (low), Y1
(med), and Y2/W (high) input signals to the board. The
blower speeds can be changed either by the variable speed
ECM manual configurations mode method (see Variable
Speed ECM Configuration Mode topic) or by using the
Aurora AID Tool directly. All three blower speeds can be set
to the same speed if desired.
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 low 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 three (3) seconds. To reset
lockout conditions with SW2-8 Off, thermostat inputs “Y1”,
“Y2”, “W”, and “DH” must be removed for at least three (3)
seconds. Lockout may also be reset by turning power off for
at least 5 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 ten (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 two (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 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.
Controls - Aurora Base Control cont.