Trane Voyager Commercial, Инструкция по установке, эксплуатации и обслуживанию

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RT-SVX34R-EN 63
Evaporator Temperature sensor (EET). If the EET drops
below 35°F for 10 continuous minutes compressors will
stage off. For dual circuit units one circuit will be
staged off initially, and then if the EET remains below
35ºF for an additional 10 minutes, the second circuit
will be staged off. For single circuit units one
compressor will be staged off initially, and then if the
EET remains below 35ºF for an additional 10 minutes,
the second circuit will be staged off. When the unit is
operating in hot gas reheat mode, only the reheat
circuit will be re-enabled if the EET rises above 45ºF.
The cooling circuit will not be re-enabled during hot
gas reheat until the unit leaves the current hot gas
reheat cycle or a dehumidification purge is initiated. If
the unit is operating in Cooling, the first circuit that de-
energized will be re-enabled when the EET rises above
45ºF. The second compressor will be allowed to re-
energize at 10 minutes after the EET rises above 45ºF or
if a purge cycle is initiated.
Drain Pan Condensate Overflow Switch
(Optional)
This input incorporates the Condensate Overflow
Switch (COF) mounted on the drain pan and the
ReliaTel Options Module (RTOM). When the
condensate level reaches the trip point for 6 continuous
seconds, the RTOM will shut down all unit function
until the overflow condition has cleared. The unit will
return to normal operation after 6 continuous seconds
with the COF in a non-tripped condition. If the
condensate level causes the unit to shutdown more
than 2 times in a 3 day period, the unit will be locked-
out of operation. A manual reset of the diagnostic
system through the Zone Sensor or Building
Automation System (BAS) will be required. Cycling unit
power will also clear the fault.
VFD Programming Parameters
See System Troubleshooting section.
Condenser Fan Sequencing Control
The condenser fans are cycled according to the
outdoor air temperature and the number of cooling
steps that are operating.
Table 38, p. 63 and Table 39,
p. 65 list the temperatures at which the A and B
Condenser Fan Outputs on the RTRM switches the fans
“Off”. The fans are switched back “ON” when the
outdoor temperature rises approximately 5° F above
the “Off” temperature.
Figure 48, p. 63 shows the condenser fans as viewed
from the top of the unit facing the control panel.
Whenever a condenser fan is cycled back “On”, the
condenser fan Outputs A and B and the compressor
steps are de-energized for approximately seven
seconds to prevent problems with fan windmill.
Figure 48. Condenser fan location
Lead fan
continuous operation
Control box
Table 38. Condenser fan/compressor sequence - std efficiency
Unit Size
(Ton)
Compressor Staging Sequence Condenser Fan Output O/A Temp. (°F)
Step 1 Step2 Step 3 Output A Output B
Fans “Off”
27.5 - 30
CPR1 (a)
NA
Fan #2 70
Fan #3 90
CPR1, 2
Fan #2 -10
Fan #3 60
35
CPR1 (a)
NA
Fan #2 65
Fan #3 85
CPR1, 2
Fan #2 -20
Fan #3 55
40 VAV only
CPR1 (b)
Fan #2 50
Fan #3, 4
70
CPR2 (c)
Fan #2 20
Fan #3, 4
60
CPR1, 2
Fan #2 -30
Fan #3, 4
50
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