Trane Voyager RT-SVX17C-EN, Установка, эксплуатация и обслуживание

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Supply Air Temperature Reset
The supply air temperature can be reset by using one of
four DIP switch configurations on the RTAM or through ICS
when a valid supply air reset setpoint with a supply air reset
amount is given. A selectable reset amount of 0
o
F to 20
o
F
via RTAM potentiometer or ICS is permissible for each type
of reset.
The amount of change applied to the supply air temperature
setpoint depends on how far the return air, zone, or outdoor
air temperature falls below the reset temperature setpoint. If
the return air, zone, or outdoor air temperature is equal to or
greater than the reset temperature setpoint, the amount of
change is zero.
If the return air, or zone temperature falls 3
o F below the re-
set temperature setpoint, the amount of reset applied to the
supply air temperature will equal the maximum amount of
reset selected.
If the outdoor air temperature falls 20
o
F below the reset
temperature setpoint, the amount of reset applied to the
supply air temperature will equal the maximum amount of
reset selected. The four DIP switch configurations are as fol-
lows:
1. None - When RTAM DIP Switch #3 and #4 are in the "Off"
position, no reset will be allowed.
2. Reset based on Return Air Temperature - When RTAM
DIP Switch #3 is "Off" and Switch #4 is "On", a selectable
supply air reset setpoint of 50
o F to 90 o F via a unit
mounted potentiometer or Tracer™ is permissible.
3. Reset based on Zone Temperature - When RTAM DIP
Switch #3 is "On" and Switch #4 is "Off", a selectable sup-
ply air reset setpoint of 50
o F to 90 o F via RTAM potenti-
ometer or Tracer is permissible.
4. Reset based on Outdoor Air Temperature - When DIP
Switch #3 and #4 are "On", a selectable supply air reset
setpoint of 0
o F to 100 o F via RTAM potentiometer or
Tracer is permissible.
Constant Volume or Variable Air Volume
Applications
Off Mode
This mode is set at the zone sensor or by ICS. During this
status, no heating, ventilation, or mechanical cooling is be-
ing performed. When switching the "System" selector to the
"Off" mode from any other mode, any diagnostic data and
diagnostic indication signal will be retained as long as the
system remains in the "Off" status. Switching the "System"
selector from the "Off" mode back to any other mode of op-
eration will reset all diagnostics.
Zone Temperature - Unoccupied Cooling (CV Only)
While a building is in an unoccupied period as designated
by a remote panel with night setback, ICS or RTRM J6-11
and J6-12, the necessary stages of cooling will cycle to
maintain the zone temperature to within the unoccupied
setpoint deadband. If an economizer is enabled, it will
modulate in an attempt to maintain the zone temperature to
within the setpoint deadband.
Zone Temperature - Unoccupied Heating
While a building is in an unoccupied period as designated
by a remote panel with night setback or ICS, the necessary
stages of heat will cycle to maintain the zone temperature to
System Operation (Continued)
within the unoccupied setpoint deadband. For VAV systems,
the IGV's or VFD's will operate at 100% during this mode. It
will be necessary to drive VAV boxes to their maximum posi-
tion through ICS programming or the factory provided VHR
relay.
Mechanical Cooling with an Economizer
The economizer is utilized to control the zone temperature
providing the outside air conditions are suitable. The
method used to determine economizer effectiveness, de-
pending on the available data, is described below in de-
scending order of complexity. The most sophisticated
method available is always used.
Two of the three methods for determining the suitability of
the outside air can be selected utilizing the potentiometer
on the Economizer Actuator, as described below:
1. Ambient Temperature - controlling the economizing cycle
by sensing the outside air dry bulb temperature. Table 14
list the selectable dry bulb values by potentiometer set-
ting.
2. Reference Enthalpy - controlling the economizer cycle by
sensing the outdoor air humidity. Table 14 list the select-
able enthalpy values by potentiometer setting. If the out-
side air enthalpy value is less than the selected value,
the economizer is allowed to operate.
Table 14
Economizer Configuration Table
3. Comparative Enthalpy - By utilizing a humidity sensor
and a temperature sensor in both the return air stream
and the outdoor air stream, the economizer will be able
to establish which conditions are best suited for main-
taining the zone temperature, i.e., indoor conditions or
outdoor conditions.
Gas Heat Control
The ignition sequence and timing are provided by a separate
heat control module. The RTRM only provides the heating
outputs to initiate 1st and 2nd stages and control the com-
bustion blower relays. Both stages of the furnace, when initi-
ated after each cycle, will start and operate for one minute
then cycle back if only one stage is required.
When the fan selection switch is in the "AUTO" mode, the
fan will be delayed from coming on for approximately 30 sec-
onds after a call for heat has been initiated. The fan will re-
main on for approximately 90 seconds after the heating set-
point has been satisfied.
Electric Heat Control
The RTRM provides two heating outputs for 1st and 2nd
stages with a 10 second delay between each stage. When
the fan selection switch is in the "AUTO" mode, the fan will
start approximately 1 second before the 1st heater stage is
activated. The fan and heater will cycle off after the heating
setpoint has been satisfied.
Selection Dry Bulb Enthalpy Value
A 73°F 27 BTU/LB Air
B 70 25 BTU/LB Air
C 67 23 BTU/LB Air
D 63 22 BTU/LB Air
Method used to determine
econmizer effectiveness
Required
Comparative Enthalpy OAT, OAH, RAT, RAH
Reference Enthalpy OAT, OAH
Reference Dry Bulb OAT
Unable to determine effectiveness OAT data is invalid or unavailable