WaterFurnace Envisio Series Console - Manual (Page 33)

33
ENVISION CONSOLE - 50 HZ INSTALLATION MANUAL
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 apply in every instance except in the event the high
pressure switch is tripped or emergency shutdown then the
compressor 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
accessory 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 disabled. As the temperature drops below the
heating set point and begins to operate in the heating
proportional band, the low capacity compressor output
(BO-2) will be enabled. A PI loop in the programming
of the control will determine when the full capacity
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
compressor 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
operate in medium speed. When the control receives
a Y2 command (BI-8) from the thermostat the full
capacity 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
accessory 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 output
(BO-2) will be enabled. A PI loop in the programming
of the control will determine when the full capacity
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
compressor 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 operate in medium
speed. When the control receives a Y2 command (BI-8)
from the thermostat the full capacity 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.
Emergency Heat/Network Enabled Output (BO5)
This output is set from the factory to enable/disable
emergency heat. If a problem occurs with the unit resulting
in the compressor being locked out in heating mode, the
control will automatically enable this output to turn on field
installed electric heat. This output is interlocked with the
blower proving input BI-6 (Blower proving sensors must
be field supplied and installed). BI-6 must be connected to
PB2 position 3 (see unit schematic) in the field if no blower
proving sensor is desired. There is a configurable parameter
available through a BAS network that must be enabled if
this output is to be commanded over the BAS network.
Envision Controls cont.