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ENVISION CONSOLE INSTALLATION MANUAL
Random Start Delay
This delay will be used after every power failure, as well as
the first time the compressor is started after the control
exits the unoccupied mode or the emergency shutdown
mode. The delay should not be less than 1 second and not
longer than 120 seconds. If the control is in test mode the
random start delay will be shortened to 5 seconds.
Compressor Fixed On Delay Time
The Compressor Fixed On Delay Time will ensure that the
compressor output (B02) is not enabled for (90) seconds
after the control receives a call to start the compressor.
This delay is adjustable from 30 – 300 seconds over a BAS
or a MUI. If the control is in test mode the Compressor
Fixed On Delay Timer will be shortened to 5 seconds.
Compressor Minimum On Delay
The compressor minimum on delay will ensure that the
compressor output is enabled for a minimum of (2) minute
each time the compressor output is enabled. This will ap-
ply in every instance except in the event the high pressure
switch is tripped or emergency shutdown then the com-
pressor output will be disable immediately.
Compressor Short Cycle Delay Time
The compressor short cycle time delay will ensure that the
compressor output will not be enabled for a minimum of
(5) minutes after it is disabled. This allows for the system
refrigerant pressures to equalize after the compressor is
disabled.
Heating Cycle
On a call for heating, the blower enable output and acces-
sory output 2 will turn on immediately after the random
start delay timer has been satisfied. If the compressor
short cycle time delay has been satisfied, the compressor
will turn on after the blower enable and accessory output
2 are on and the fixed compressor start delay timers have
been satisfied.
Auxiliary heat output can be controlled over the BAS.
Set Point Control Mode
In set point control mode the reversing valve output
will be disabled. As the temperature drops below the
heating set point and begins to operate in the heating
proportional band, the low capacity compressor out-
put (BO-2) will be enabled. A PI loop in the program-
ming of the control will determine when the full capac-
ity compressor output (BO-4) is to be enabled. The
compressor must be operating in low capacity for a
minimum of 30 seconds before the full capacity com-
pressor output can be enabled. During low capacity
compressor operation the ECM2 blower will operate
in medium speed and will operate in high speed when
the compressor is operating at full capacity.
Thermostat Control Mode
In thermostat mode the compressor will be cycled
based on Y1 and Y2 calls from a room thermostat.
When the control receives a Y1 command (BI-7) from
the thermostat the low capacity compressor output
(BO2) will be enabled and the ECM2 blower will oper-
ate in medium speed. When the control receives a Y2
command (BI-8) from the thermostat the full capac-
ity compressor output will be enabled and the ECM2
blower will operate in high speed. During the heating
cycle the reversing valve will be commanded into the
off position.
Cooling Cycle
On a call for cooling, the blower enable output and acces-
sory output 2 will turn on immediately after the random
start delay timer has been satisfied. If the compressor
short cycle time delay has been satisfied, the compressor
will turn on after the blower enable and accessory output
2 are on and the fixed compressor start delay timers have
been satisfied.
Set Point Control Mode
In set point control mode the reversing valve output
will be enabled. As the temperature falls below the
cooling set point and begins to operate in the cooling
proportional band, the low capacity compressor out-
put (BO-2) will be enabled. A PI loop in the program-
ming of the control will determine when the full capac-
ity compressor output (BO-4) is to be enabled. The
compressor must be operating in low capacity for a
minimum of 30 seconds before the full capacity com-
pressor output can be enabled. During low capacity
compressor operation the ECM2 blower will operate
in medium speed and will operate in high speed when
the compressor is operating at full capacity.
Thermostat Control Mode
In thermostat mode the compressor will be cycled
based on Y1 and Y2 calls from a room thermostat.
When the control receives a Y1 command (BI-7) from
the thermostat the low capacity compressor output
(BO2) will be enabled and the ECM2 blower will oper-
ate in medium speed. When the control receives a Y2
command (BI-8) from the thermostat the full capac-
ity compressor output will be enabled and the ECM2
blower will operate in high speed. During the cooling
cycle the reversing valve will be commanded into the
“ON” position.
Envision Console Controls
