TROUBLESHOOTING
The FlotronicTY II control has many features to aid the technicians in troubleshooting a Flotronic II Chiller. By us- ing keypad and display module and status function, actual operating conditions of the chiller are displayed while unit is running. Test function allows proper operation of com- pressors, compressor unloaders, fans, EXVs and other com- ponents to be checked while chiller is stopped. Service function displays how configurable items are configured. If an op- erating fault is detected, an alarm is generated and an
alarm code(s) is displayed under the subfunction m I;;;;] ,
along with an explanation of the fault. Up to 5 current alarm codes are stored. For checking specific items, see Table 9.
Checking Display Codes - To determine how ma- chine has been programmed to operate, check diagnostic
information (( w ) and operating mode displays (/ Fi ).
If no dismay annears, follow procedures in Control Mod-
ules section+onlpage 64. If display is working, continue as follows:
1. Note all alarm codes displayed, F\ bi .
2.Note all operating mode codes displayed, MH .
3.Note leaving chilled water temperature set point in ef-
fect and current leaving water temperature, MFI .
If machine is running, compare the “in effect” leaving water temperature set point with current water tempera- ture. Remember, if reset is in effect, the values may be different because machine is operating to the modified chilled water set point, If current temperature is equal to set point, but set point is not the one desired, remember that if dual set point has been selected in the schedule function, there are 2 set points to which the machine can be operating. Check the programming of schedule func- tion to see if occupied or unoccupied set point should be in effect.
Unit Shutoff - To shut unit off, move LOCAL/
plete the pumpout cycle. Lag compressors stop immediately, and lead compressors run to complete pumpout.
Complete Unit Stoppage - Complete unit stop-
page can be caused by any of the following conditions:
1
1. Cooling load satisfied
2. Remote ON/OFF contacts open
3. Programmed schedule
4. | Emergency stop command from CCN |
5. | General power failure |
6. | Blown fuse in control power feed disconnect |
7. | Open control circuit fuse |
13.Cooler entering or leaving fluid thermistor failure
14.Low transducer supply voltage
15. Loss of communications between processor module and other control modules
16. Low refrigerant pressure
Single Circuit Stoppage - Single circuit stoppage can be caused by the following:
1 Low oil pressure in lead compressor
2.Open contacts in lead compressor
3.Low refrigerant pressure
4.Thermistor failure
5.Transducer failure
6.Ground fault in lead compressor indicator (indicator is
7.High suction superheat
8.Low suction superheat
9.Lead compressor circuit breaker trip+ Stoppage of one circuit by a safety device action does not affect other circuit. When a safety device trips on a lead compres- sor, circuit is shut down immediately and EXV closes.
10.Ground fault for any circuit compressor
Lag Compressor Stoppage - Lag compressor stop- page can be caused by the following:
1, Open contacts in
2.Compressor ground fault (indicator is
3.Compressor circuit breaker trip
4.Not required to run to meet cooling load requirement
If stoppage occurs more than once as a result of any of the above safety devices, determine and correct the cause before attempting another restart.
Restart Procedure - After cause for stoppage has been corrected, restart is either automatic or manual, depending on fault. Manual reset requires that LOCAL/ENABLE-
POWER FAILURE EXTERNAL TO THE UNIT - Unit restarts automatically when power is restored.
Typical Stoppage Faults and Reset Types
8. | |
| position |
9. | Freeze protection trip |
10.Low flow protection trip
11.Open contacts in chilled water flow switch (optional)
12.Open contacts in any auxiliary interlock. Terminals that are jumpered from factory are in series with control switch. Opening the circuit between these terminals places unit in stop mode, similar to moving the control switch to STOP position. Unit cannot start if these contacts are open. If they open while unit is running, unit pumps down and stops .
Chilled Water, Low Flow Chilled Water, Low Temperature
Chilled Water Pump Interlock
Control Circuit Fuse Blown
Low Refrigerant Pressure
Low Oil Pressure
Discharne Gas Thermostat Open
Manual reset
Auto reset first time, manual if repeat
Manual reset
Unit restarts automatically when power is restored
Manual reset
Auto reset first time, then manual if within same day
Manual reset Manual reset
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