Viconics VT7607 BACnet Integration Guide (First Release 1000 Series) - Manual (Page 22)

22
Symptom Possible Cause Corrective Action
Wrong mode selected Select cooling mode
Thermostat in Unoccupied
mode Select Occupied Hold in Schedule hold or Override to
force the thermostat Occupied cooling setpoint
Anticycle delay active Wait, the anticycling period will end and the
equipment will start
Cooling setpoint is satisfied Lower the cooling setpoint
Cooling lockout attained 1. Mode is locked out based on outside air
temperature
2. Change configuration parameter C Lock to value -
40 °F ( -40 °C ) to by-pass lockout
Thermostat will not call
for cooling
Wiring error 1. Start the Fan by forcing the Fan ON mode
2. Put a jumper across terminals RC & Y1. The
cooling should come ON. If it does not, verify wiring
Wrong mode selected The thermostat will not
turn on the fan
Wiring error
1. Start the Fan by forcing the Fan ON mode
2. Put a jumper across terminals RC & G. The fan
should come ON. If it does not, verify wiring
Digital display shows
missing digits or erratic
segments Defective display Replace thermostat
RH sensor is out of range Verify the remote RH sensor or the internal RH
sensor
System Mode in Cool or Off Change the system mode parameter to heat
System Mode in Auto but a
cooling demand at the
thermostat Wait: when a heating demand will occur at the
thermostat, humidification will resume
Thermostat will not call
for humidification
High limit sensor is controlling
the humidifier output by
forcing it to 0% Wait: when the supply humidity will drop below the
high limit setpoint, humidification will resume.
RH sensor is out of range Verify the remote RH sensor or the internal RH
sensor
System Mode in Heat or Off Change the system mode parameter to cool
System Mode in Auto but a
heating demand at the
thermostat Wait: when a cooling demand will occur at the
thermostat, dehumidification will resume
Thermostat will not call
for dehumidification
Outside air temperature is
below the Dhu OALK
parameter Change the Dhu OALK parameter to a value that will
enable the dehumidification, if desired.