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

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System Operation (Continued)
Zone Temperature - Occupied Cooling (CV only)
When the unit is in the cooling mode and the zone tempera-
ture raises above the cooling setpoint controlband, the
economizer and the compressor stages will be cycled as re-
quired by the zone sensor, remote panel, or Tracer®.
Table 12 lists the percentages the dampers will open based
on these conditions.
Table 12
Percent of Damper Travel
Zone Temp - Econ Setpoint
o
F
Zone - ODT 0.0 - 0.5 0.5 - 1.0 1.0 - 2.0 2.0 - 3.0 3.0 - 5.0 > 5.0
0 - 7 F 0% 3% 9% 30% 90% 100%
7 - 14 F 0% 2% 6% 20% 60% 100%
> 14 F 0% 1% 3% 10% 30% 100%
Zone Temperature - Occupied Heating (CV only)
When the unit is in the heating mode and the zone tempera-
ture falls below the heating setpoint controlband, the neces-
sary stages of heat will cycle to raise the temperature to
within the setpoint controlband.
Supply Fan (CV only)
When the Fan Selection Switch is in the "AUTO" position
and a call for cooling is initiated, the supply fan will delay
starting for approximately one second. When the Fan Selec-
tion Switch is in the "ON" position, the supply fan will run
continuously. If air flow through the unit is not proven by the
differential pressure switch (factory setpoint 0.15 " w.c.)
within 40 seconds nominally, the RTRM will shut off all me-
chanical operations, lock the system out, send a diagnostic
to ICS, and the SERVICE LED output will pulse. The system
will remain locked out until a reset is initiated either manu-
ally or through ICS or a mode transition from OFF to a non-
OFF mode.
Supply Air Tempering (CV only)
This function allows the supply air temperature to be main-
tained within a low limit parameter during minimum ventila-
tion periods. When the system is in the "Heating" mode of
operation, the low limit parameter is equal to the heating
setpoint minus 10 degrees F.
When an economizer is installed, air tempering is allowed
with ICS
TM when the fan system switch is in the "ON" posi-
tion with no call for heating. If the supply air temperature
falls 10 degrees F below the heating setpoint, the next
available stage of heat will be turned on. It will remain on
until the supply air temperature reaches 10 degrees above
the heating setpoint.
While economizing, if the supply air temperature falls below
50
o F, the damper will not be allowed to open any further un-
til the supply air temperature rises above 50
o
F. If the supply
air temperature falls below 45
o
F, the dampers will be driven
to minimum position and held there until the supply air tem-
perature rises above 50
o
F.
The mechanical cooling is disabled while in an economiz-
ing state until two conditions are met;
1. The economizer dampers have been fully open for three
minutes, and;
2. The calculated rate of change in the zone temperature is
less than 12 o F per hour.
If the economizer is disabled due to unsuitable conditions,
the economizer is at the selected minimum position when
the supply fan is "On", and is closed when the supply fan is
"Off". The mechanical cooling will cycle as though the unit
had no economizer.
Mechanical Cooling without an Economizer (CV only)
Mechanical cooling is used to maintain the zone tempera-
ture. The RTRM is designed to limit the compressor cycle
rates to within 10 cycles per hour based on the minimum
compressor "on" and "off" times.
It stages the mechanical cooling to control the zone tem-
perature to /- 2
o
F of the sensor setpoint at the
sensed location. Table 13 list the compressor stepping se-
quence.
Table 13
Compressor Staging with Lead/Lag Disabled
Unit "ON" "OFF"
Model Step 1 Step 2 Step 3 Step 3 Step 2 Step 1
27.5 - 35 CPR 1* CPR 1, 2 N/A N/A CPR 1, 2 CPR 1
40 - 50 CPR 1** CPR 2,3*** CPR 1, 2, 3 CPR 1, 2, 3 CPR 2, 3*** CPR 1**
* - Single circuit, dual manifolded compressors
** - Number one refrigeration circuit, Stand alone compressor, is "On".
*** - First Stage is "Off", Number two refrigeration circuit, manifolded
compressor pair operating simultaneously, is "On".