Trane Voyager Commercial, Инструкция по установке, эксплуатации и обслуживанию

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140 RT-SVX34R-EN
Table 79. Troubleshooting (continued)
SYMPTOM PROBABLE CAUSE RECOMMENDED ACTION
T. Economizer modulates, but system
does not seem to operate as
efficiently as in the past.
1. Comparative enthalpy setup, RAS or RHS failed.
System is operating using Reference enthalpy.
1. Check the return air sensor (RAS) at connector
P10 by disconnecting P10 from RAT on the ECA.
Check for resistance between P10-1 and P10-2, refer
to the Resistance versus Temperature Chart. Replace
the sensor if necessary. Check the return air
humidity sensor (RHS) by measuring the operating
current at terminals RAH-1 and RAH-2 on the ECA.
Normal operating current is 4 to 20 milliamps mA.
Note: The humidity sensors are polarity sensitive,
and will not operate if connected backwards.
2. Reference enthalpy setup, OHS has failed. System
is operating using dry bulb control.
2. Check the outside humidity sensor (OHS) by
measuring the operating current at terminals OAH-1,
and OAH-2 on the ECA. Normal operating current is 4
to 20 milliamps mA.
3. Comparative enthalpy setup, OHS has failed.
System is operating using dry bulb control.
3. Perform #2 above.
U. Power Exhaust will not operate.
1. Exhaust motor has failed.
1. Check the exhaust fan motor, and replace if
necessary.
2. XFR has failed.
2. Check the exhaust fan contactor (XFR). Replace if
necessary
3. ECA has failed.
3. Perform the ECA Test Procedures discussed
previously.
4. XFSP has Failed
4. Perform the Exhaust Fan Setpoint Test Procedures
discussed previously.
V. VFD will not operate properly
1. RTAM has Failed
1. Perform the RTAM Test Procedures discussed
previously.
2. VFD has Failure 2. Check the VFD
3. Setpoint Failure
3. Perform the VFD Setpoint Test Procedures
discussed previously.
4. RTOM has Failed
4. Perform the RTOM Test Procedures discussed
previously.
W. Power Exhaust Fan cycles ON/OFF
1. Space Pressure Deadband is too narrow 1. Increase the Space Pressure Deadband.
2. Space Pressure Setpoint is too high/low
2. Verify Building Pressure with maximum building
exhaust enabled. Adjust Space Pressure Setpoint
accordingly.
Table 80. Component failure mode
COMPONENT FAILURE RESPONSE NORMAL RANGE DIAGNOSTIC
(OAS) Outdoor Air Sensor
1. Economizer in minimum
position. Will not modulate.
-55 to 175F / 680K to 1.2K
Heat and cool failure output at RTRM J6-7
to J6-6 and RTRM J6-8 to J6-6. Heat and
cool LED's blink at ZSM. Check at RTRM
connector P8, between P8-1 & P8-2.
2. ODM3 will not cycle off
(runs continuously).
-55 to 175F / 680K to 1.2K Check at RTRM connector P8.
(RAS) Return Air Sensor
Economizer operates using
Reference Enthalpy
0 to 209 F / 90K to 7.1K
ECA LED 4 Flashes. Check at ECA
connector P1 between P10-1 & P10-2.
(MAS) Supply Air Sensor
Economizer in minimum
position, will not modulate.
0 to 209 F / 90K to 7.1K
ECA 8 flashes.
(OHS) Outdoor Humidity
Sensor Uses Dry Bulb operation and
economizes if below 60 F DB.
4 to 20 mA / 10 to 90% RH
Honeywell C7600A. ECA 6 flashes. Check at ECA OAH-1 and
OAH-2 by measuring current draw.
(RHS) Return Humidity
Sensor
Economizer operates using
Reference Enthalpy.
4 to 20 mA / 10 to 90% RH
Honeywell C7600A. Check at ECA ECA 3 flashes. RAH-1 and
RAH-2 by measuring current draw.
Remote Minimum position
Potentiometer
1Economizer modulates but
minimum position stays at
zero.
Potentiometer range 50 to
200 Ohms. *NONE* Check resistance at ECA P and P1
50 to 200 Ohms.
Cooling Setpoint (CSP) for CV
or SZ VAV ZSM slide
potentiometer
Uses HSP and CSP CSP= HSP
+ 4 F or use RTRM Default
Mode.
100 to 900 Ohms Use ZSM
Test Procedures. *NONE* Check at terminals 2 and 3 on
ZSM
Heating Setpoint (HSP) for CV
or SZ VAV ZSM slide
potentiometer
Uses CSP and HSP HSP= CSP -
4 F. 100 to 900 Ohms Use ZSM
Test Procedures. *NONE* Check at terminals 2 and 5 on
ZSM.
TDL1, TDL2 or TDL3
(Temperature Discharge
Limit)
Comp1, Comp2 or Comp3 will
not operate.
Open 230 F +/- 6.5 F, Close
180 F +/- 12.5 F, Normally
closed
Cool Failure Output at RTRM J6-8 to J6-6
LED blinks at ZSM.
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