Trane SEHJ090-162, Инструкция по установке, эксплуатации и обслуживанию

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Unit Startup
RT-SVX24J-EN 107
sequence of operation. As you review the sequence of
operations, remember these points:
1. The high limit switch will trip if exposed to a
temperature greater than the trip point, and will reset
automatically once the temperature falls below the
reset point.
2. The linear high limit switch is encased in a capillary
that extends across the unit supply air opening. The
limit will trip if any 6” span of the capillary exceeds the
trip point. Refer to
Table 42, p. 133 .
3. Electric heat will only energize if both of the high limit
safety controls are closed.
Electric Heat—CV, VAV Daytime Warm-up
CV electric heat operation is done with discrete stages of
electric heat. Stages 2 and 3 will not energize unless Stage
1 is already operating and unable to satisfy the heating
load. The heat will be staged to control to the Heating
Setpoint.
VAV Active Occupied Discharge Heating
When the changeover input is closed (or when
commanded by BAS) the unit will control discrete stages
of electric heat to the active supply air heating setpoint.
VAV occupied electric heating operation is done with
discrete stages (steps) of electric heat.The heat staging is
dependent on unit tonnage and heater selection.The heat
will be staged to control to the Supply Air Heating
Setpoint.
SZVAV Occupied Heating
Single Zone VAV heating will only be available with
modulating types of heat - IPak II units can use hydronic
and modulating gas and will include electric heat. During
SZVAV heating, the unit will calculate a discharge heating
setpoint based on zone heating demands, and the unit will
modulate heat to maintain the discharge temperature to
this setpoint.
Demand Control Ventilation Sequence of
Operation
Note: CO
2
sensor used with Demand Control Ventilation
must be powered from an external power source or
separate 24 VAC transformer.
Sequence of Operation without TRAQ
If the space CO
2
level is greater than or equal to the Design
Minimum CO
2
Setpoint, the outdoor air damper will open
to the Design Minimum Outdoor Air Damper Setpoint. If
there is a call for economizer cooling, the damper may be
opened further to satisfy the cooling request.
If the space CO
2
level is less than or equal to the DCV
Minimum CO
2
Setpoint, the outdoor air damper will close
to the DCV Minimum Outdoor Air Damper Setpoint. If
there is a call for economizer cooling, the damper may be
opened further to satisfy the cooling request.
If the space CO
2
level is greater than the DCV Minimum
CO
2
Setpoint and less than the Design Minimum CO
2
Setpoint, the outdoor air damper position is modulated
proportionally to the space CO
2
level relative to a target
position between the DCV Minimum CO
2
Setpoint and the
Design Minimum CO
2
Setpoint. If there is a call for
economizer cooling, the damper may be opened further to
satisfy the cooling request.
Sequence of Operation with TRAQ
If the space CO
2
level is greater than or equal to the Design
Minimum CO
2
Setpoint, the outdoor air damper will open
to the Design Minimum Outdoor Air Flow Setpoint. If there
is a call for economizer cooling, the damper may be
opened further to satisfy the cooling request.
If the space CO
2
level is less than or equal to the DCV
Minimum CO
2
Setpoint, the outdoor air damper will close
to the DCV Minimum Outdoor Air Flow Setpoint. If there is
a call for economizer cooling, the damper may be opened
further to satisfy the cooling request.
If the space CO
2
level is greater than the DCV Minimum
CO
2
Setpoint and less than the Design Minimum CO
2
Setpoint, the outdoor air damper position is modulated
proportionally to the space CO
2
level relative to a target
position between the DCV Minimum CO
2
Setpoint and the
Design Minimum CO
2
Setpoint. If there is a call for
economizer cooling, the damper may be opened further to
satisfy the cooling request.
Return Fan Sequence of Operation
Whenever the Supply Fan is turned ON, the return fan will
be turned ON. The speed of the return fan will control to
the Return Air Plenum Pressure Target. The target is
calculated internal to the control and will be between the
Minimum Return Air Plenum Pressure Setpoint and the
Maximum Return Air Plenum Pressure Setpoint
depending on unit operation conditions. A Return Air
Pressure High Limit will be set at 3.5 IWC. If the pressure
inside the return plenum exceeds the limit the unit will
shut down.
Unit Clustering
A cluster is a master unit and one or more similarly
configured slave units operative cooperatively, as a group,
to provide higher capacity and/or redundancy at partial
capacity. Clustering is accomplished by binding variables
between unit LCI-I modules, communicating common
setpoints and allowing each unit to run independent
algorithms. A cluster will share a common supply and
return duct network.
Low Charge Protection
For each refrigeration circuit, the entering and leaving
evaporator temperatures are used to calculate superheat.
When the calculated superheat exceeds the Evaporator