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14
LEGEND
Table 4 —
Humidi-MiZer Troubleshooting
PROBLEM
CAUSE
REMEDY
Subcooling Reheat Mode Will
Not Activate
General cooling mode problem
See Cooling Service Troubleshooting (Table 5).
No dehumidification demand
See No Dehumidification Demand, below.
CRC relay operation
See CRC Relay Operation, below.
Circuit RLV, CLV or LDV valve problem
See CLV, RLV or LDV Valve Operation, below.
Hot Gas Reheat Mode Will Not
Activate
General cooling mode problem
See Cooling Service Troubleshooting (Table 5).
No dehumidification demand
See No Dehumidification Demand, below.
CRC relay operation
See CRC Relay Operation, below.
Circuit RLV, CLV or LDV valve problem
See CLV, RLV or LDV Valve Operation, below.
Circuit RDV valve is not open
See RDV Valve Operation, below.
Outdoor temperature too low
Check the LTLO is functioning properly.
No Dehumidification Demand
Relative humidity setpoint too low — Humidistat Check/reduce setting on accessory humidistat.
Relative humidity setpoint too low — RH sensor On units with DDC, verify the RH sensor is reading properly and
that the setpoint is set properly.
No humidity signal
Check wiring. Check humidistat or humidity sensor.
CRC Relay Operation
No 24V signal to input terminals
Check the dedicated Humidi-MiZer transformer for voltage or
tripped circuit breaker.
Check wiring.
Check transformer and circuit breaker.
No power to output terminals
Check wiring.
Relay outputs do not change state
Replace faulty relay.
RLV, CLV or LDV Valve
Operation
No 24V signal to input terminals
Check CRC Relay Operation.
Check wiring.
Check transformer and circuit beaker or fuses.
Solenoid coil burnout
Check continuous over-voltage is less than 10%.
Check under-voltage is less than 15%.
Check for missing coil assembly parts.
Check for damaged valve enclosing tube.
Stuck valve
Replace valve. Replace filter drier.
RDV Valve Operation
(NOTE: Normally Closed
When De-energized)
No 24V signal to input terminals
Check RDV relay operation.
Check wiring.
Check transformer and circuit breaker or fuses.
Solenoid coil burnout
Check continuous over-voltage is less than 10%.
Check under-voltage is less than 15%.
Check for missing coil assembly parts.
Check for damaged valve enclosing tube.
Stuck valve
Replace valve. Replace filter drier.
Low Latent Capacity in
Subcooling or Hot Gas
Reheat Modes
CLV valve open or leaking
See CLV Valve Operation, above.
Low Sensible Capacity in
Normal Cool or Subcooling
Reheat Modes
RDV valve open or leaking
See RDV Valve Operation, above.
Low Suction Pressure and
High Superheat During
Normal Cool Mode
General cooling mode problem
See Cooling Service Troubleshooting (Table 5).
RDV valve open or leaking
See RDV Valve Operation, above.
Low Suction Pressure and
High Discharge Pressure
General cooling mode problem
See Cooling Service Troubleshooting (Table 5).
Both RLV and CLV valves closed
See RLV and CLV Valve Operation, above.
RDV Valve Cycling On/Off
Hot Gas Reheat mode low suction pressure
limit
Normal Operation During Mixed Circuit Subcooling and Hot Gas
Reheat Modes at Lower Outdoor Temperatures.
Circuit B Will Not Operate
With Circuit A Off
Normal operation. Motormaster outdoor fan
control requires operation of circuit A.
None
CRC
—
Cooling/Reheat Control
CLV
—
Cooling Liquid Valve
RLV
—
Reheat Liquid Valve
RH
—
Relative Humidity
RDV
—
Reheat Discharge Valve
Summary of Contents for 48TC series
Page 40: ...40 Fig 56 Typical IGC Wiring Diagram...
Page 41: ...41 Fig 57 Integrated Gas Control IGC Board RED LED STATUS...
Page 47: ...47 Fig 62 RTU Open Overlay for Economizer Wiring...
Page 48: ...48 Fig 63 VFD Overlay for W2770 Controller Wiring...
Page 97: ...97 Fig D 48TC D17 D30 Power Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS...
Page 98: ...98 Fig E 48TC D17 D30 Power Diagram 460 3 60 APPENDIX D WIRING DIAGRAMS...
Page 99: ...99 Fig F 48TC D17 D30 Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS...
Page 100: ...100 Fig G 48TC D17 D30 Control Diagram with Humidi MiZer System APPENDIX D WIRING DIAGRAMS...
Page 104: ...104 Fig K PremierLink System Control Wiring Diagram APPENDIX D WIRING DIAGRAMS...
Page 106: ...106 Fig M RTU OPEN Wiring Diagram APPENDIX D WIRING DIAGRAMS...
Page 107: ...107 Fig N RTU OPEN Wiring Diagram with Humidi MiZer System APPENDIX D WIRING DIAGRAMS...
Page 109: ......