68
RT-SVX063E-EN
S
Stto
op
pp
pe
ed
d
Stopped is a Unit mode when control is prevented from
running. For example, if External Auto/Stop binary
input is active,
External Auto Stop
will be listed as a
sub-mode.
R
Ru
un
n IIn
nh
hiib
biitt
The unit is currently being inhibited from starting and
running. For example, if a Power Up Delay timer is
preventing the unit startup,
Power Up Delay Inhibit
(Min:Sec)
will be listed with the remaining minutes and
seconds to expire.
A
Au
utto
o
The unit supply fan is typically running to provide
ventilation.
Idle
is listed as a sub-mode on startup
when the control is determining an initial heating or
cooling demand. Additional sub-modes are listed when
gas heat diagnostics are preventing heat operation.
R
Ru
un
nn
niin
ng
g
Running is a Unit mode then normal heating, cooling
and ventilation control functions are active. The supply
fan is running. Up to four Running sub-modes will be
listed on the user interface, Operating Modes screen.
Circuit
Circuit modes provide refrigerant circuit level operating
state and sub-mode information. When the unit has
two circuits, the user interface will provide both Circuit
1 and Circuit 2 mode and sub-mode information.
S
Stto
op
pp
pe
ed
d
The circuit is not running, and cannot run without
removing a condition. For example,
Diagnostic
Shutdown – Manual Reset
sub-mode is displayed when
a diagnostic has caused a circuit level shutdown and a
manual reset is required.
R
Ru
un
n IIn
nh
hiib
biitt
The circuit is currently being inhibited from starting
(and running), but may be allowed to start if the
inhibiting or diagnostic condition is cleared. For
example: Low Ambient Temp is displayed when
outdoor air temperature is below the Low Ambient
Lockout Setpoint; the circuit is being inhibited from
starting.
A
Au
utto
o
The circuit is not running but expected to start given
the proper conditions are satisfied.
W
Wa
aiittiin
ng
g tto
o S
Stta
arrtt
The circuit is going through the necessary steps to
allow the circuit to start; for example, EXV is being
commanded to a pre-position prior to starting a
compressor.
R
Ru
un
nn
niin
ng
g
A compressor on a given circuit is currently running.
R
Ru
un
nn
niin
ng
g —
— L
Liim
miitt
The circuit is currently running; however, the operation
of the unit/compressors is actively limited by the
controls. Active compressor protection sub-modes will
be listed. See Compressor Protections section for more
information.
S
Sh
hu
uttttiin
ng
g D
Do
ow
wn
n
The circuit is preparing to de-energize the compressor.
For example, Diagnostic Shutdown – Manual Reset is
displayed when the circuit is shutting down on a
latching diagnostic.
Unit Sub-Modes
Morning Warm Up
Morning Warm Up is an optional feature when heat is
configured and can be Enabled or Disabled. Morning
Warm Up is a mode often used during building
unoccupied periods and optimal start applications to
rapidly increase the space temperature, as efficiently as
possible, before building occupancy. The outdoor air
damper minimum position setpoint will be overridden
to 0%, ventilation air is not provided during Morning
Warm Up.
For Morning Warmup to initiate on a transition from
Unoccupied to Occupied, Space temperature control
units must be in Heat, Max Heat, or Auto. Discharge air
control units can also initiate Morning Warm Up on an
Off to Occupied transition.
For all equipment types (Constant Volume, Multi Zone-
VAV, and Single Zone VAV): On a transition from
Unoccupied to Occupied or Occupied-Standby, and
with a valid space temperature 1.5° F below the
Morning Warmup Setpoint, morning warm up
operation initiates. Heat Cool Mode Status reports
maximum heat if the heat type requires full airflow and
VAV Box Relay binary output will energize (see
Maximum Heat for details). Otherwise, heat types that
allow modulating airflow will report heat.
The Symbio 800 operates in a discharge air control
mode delivering heating capacity per Discharge Air
Heating Setpoint Active; this provides flexibility when
100% heat capacity in not desired. The supply fan
operates at max speed on Constant Volume
Units. Variable air volume discharge air control units
will operate the supply fan per Duct Static Pressure
Setpoint, if the installed heat type allows. (See Heat
Types section for more information).
When 60 minutes expires or when space temperature
equals or exceeds the Morning Warmup Setpoint,
Morning Warm Up mode will terminate.
Morning Warm Up mode can also be commanded via
Heat Cool Mode Request from a building automation
system or external control. In this case, the unit
remains in Morning Warm Up mode indefinitely until
the commanded mode is removed or changed. When
the space temperature exceeds the Morning Warmup
Setpoint, heating capacity is disabled but the supply
S
Se
eq
qu
ue
en
ncce
e o
off O
Op
pe
erra
attiio
on
n
