Unit Startup
44
RT-SVX46G-EN
While economizing, the mechanical cooling is disabled
until the economizer dampers have been fully open for
three minutes. If the economizer is disabled due to
unsuitable conditions, the mechanical cooling will cycle as
though the unit had no economizer.
Note:
The RTRM is designed to maintain a selectable
supply air temperature of 40°F to 90°F with a +/-
3.5°F deadband. However, to reduce the risk of
evaporator coil freeze-up in Precedent and Voyager
Light Commercial applications, supply air
temperature should not be set below 50°F.
Zone Temperature Control without a Night
Setback Panel or ICS - Unoccupied Cooling
When a field supplied occupied/unoccupied switching
device is connected between RTRM J6-11 and RTRM J6-
12, both the economizer and the mechanical cooling will
be disabled.
Zone Temperature Control without a Night
Setback Panel or ICS - Unoccupied Heating
When a field supplied occupied/unoccupied switching
device is connected between RTRM J6-11 and J6-12 and
DWU is enabled, the zone temperature will be controlled
at 10°F below the Morning Warm-up setpoint, but not less
than 50°F, by cycling one or two stages of either gas or
electric heat, whichever is applicable.
Morning Warm-up (MWU) Control
Note:
Heating control only used on Multi-Zone VAV
applications.
Morning warm-up is activated if the zone temperature is at
least 1.5°F below the MWU setpoint whenever the system
switches from unoccupied to occupied status. The MWU
setpoint may be set from the unit mounted potentiometer
or a remotely mounted potentiometer. The setpoint
ranges are from 50°F to 90°F. When the zone temperature
meets or exceeds the MWU setpoint, the unit will switch to
the “Cooling” mode. The economizer will be held closed
during the morning warm-up cycle.
Daytime Warm-up (DWU) Control
Note:
Heating control only used on Multi-Zone VAV
applications.
Daytime warm-up is applicable during occupied status
and when the zone temperature is below the initiation
temperature. It can be activated or deactivated through
ICS or a night setback zone sensor. If ICS or a night setback
zone sensor is not utilized, DWU can be activated by
setting the DWU enable DIP switch (RTAM) to ON and
supplying a valid morning warm-up setpoint.
The unit is shipped with a morning warm-up setpoint
configured and the daytime warm-up function is activated
(switch on). Opening the DWU enable switch will disable
this function.
If the system control is local, the DWU initiation setpoint is
3°F below the morning warm-up setpoint. The termination
setpoint is equal to the morning warm-up setpoint.
If the system control is remote (Tracer®), the DWU
setpoint is equal to the Tracer® occupied heating setpoint.
The initiation and termination setpoints are selectable
setpoints designated by Tracer®.
When the zone temperature meets or exceeds the
termination setpoint while the unit is in an occupied,
“Auto” mode or switched to the “Cooling” mode, the unit
will revert to the cooling operation.
If an occupied “Heating” mode is selected, the unit will
only function within the DWU perimeters until the system
is switched from the “Heat” mode or enters an unoccupied
status.
Return Air Smoke Detector
The return air smoke detector is designed to shut off the
unit if smoke is sensed in the return air stream. Sampling
the airflow entering the unit at the return air opening
performs this function.
In order for the smoke detector to properly sense smoke in
the return air stream, the air velocity entering the unit must
be in accordance with manufacturers recommended
airflow limits.
Economizer Startup
Minimum Position Setting
ReliaTel™ Control:
Momentarily jump across the Test 1 and Test 2
terminals on LTB1 one additional time if continuing
WARNING
Live Electrical Components!
Failure to follow all electrical safety precautions when
exposed to live electrical components could result in
death or serious injury. When necessary to work with
live electrical components, have a qualified licensed
electrician or other individual who has been properly
trained in handling live electrical components perform
these tasks.
WARNING
Rotating Components!
Failure to follow all safety precautions below could
result in rotating components cutting and slashing
technician which could result in death or serious injury.
During installation, testing, servicing and
troubleshooting of this product it may be necessary to
work with live and exposed rotating components. Have
a qualified or licensed service individual who has been
properly trained in handling exposed rotating
components, perform these tasks.
