WaterFurnace Envision2 - Manual (Page 30)

30
ENVISION 2 COMPACT - 50 HZ INSTALLATION MANUAL
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 - set points shall be either -1.1°C or
-9.4°C. 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 low
speed immediately and the compressor is energized
10 seconds after the Y1 input is received. The variable
speed ECM blower motor is switched to medium speed 15
seconds after the Y1 input.
Heating, 2nd Stage (Y1, Y2) - The compressor will be
staged to full capacity 20 seconds after Y2 input is
received. The variable speed ECM blower will shift to high
speed 15 seconds after the Y2 input is received.
Heating, 3rd Stage (Y1, Y2, W) - The first stage of electric
heat is energized 10 seconds after the W command is
received. If the demand continues the second stage of
electric heat will be energized after 5 minutes.
Emergency Heat (W) - The blower will be started on low
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 high speed. If the
emergency heat demand is not satisfied after 2 minutes the
second electric heat stage will be energized.
Blower (G) - The blower will start immediately upon
receiving a thermostat G command. If there are no other
commands from the thermostat the variable speed ECM
will run on low speed until the G command is removed.
Regardless of blower input (G) from the thermostat, the
blower will remain on low speed for 30 seconds at the end
of each heating cycle.
Cooling Operation
In all cooling operations, the reversing valve directly tracks
the O input. Thus, anytime the O input is present, the
reversing valve will be energized.
Cooling, 1st Stage (Y1,O) - The blower is started on low
speed immediately and the compressor is energized 10
seconds after the Y1 input is received. The variable speed
ECM blower motor is switched to medium speed 15 seconds
after the Y1 input.
Cooling, 2nd Stage (Y1, Y2, O) - The compressor will be
staged to full capacity 20 seconds after Y2 input was
received. The variable speed ECM blower will shift to high
speed 15 seconds after the Y2 input was received.
Blower (G) - The blower will start immediately upon
receiving a thermostat G command. If there are no other
commands from the thermostat the variable speed ECM
will run on low speed until the G command is removed.
Regardless of blower input (G) from the thermostat, the
blower will remain on low speed for 30 seconds at the end
of each heating, cooling, emergency heat, and reheat cycle.
Dehumidification (Y1, O, DH or Y1, Y2, O, DH) - When a
DH command is received from the thermostat during a
compressor call for cooling the variable speed ECM blower
speed will be reduced by 15% to increase dehumidification.
Emergency Shutdown - Four (4) seconds after a valid ES
input, P2-7 is present, all control outputs will be turned off
and remain off until the emergency shutdown input is no
longer present. The first time that the compressor is started
after the control exits the emergency shutdown mode,
there will be an anti-short cycle delay followed by a random
start delay. Input must be tied to common to activate.
Continuous Blower Operation - The blower output will
be energized any time the control has a G input present,
unless the control has an emergency shutdown input
present. The blower output will be turned off when G input
is removed.
Controls - Aurora Base Control cont.