Page 45
TROUBLESHOOTING
APPENDIX
SYMPTOM
CAUSE and REMEDY
Lo is
continually
displayed
−
Temperature is below minimum 42.0°F
(5.5
°
C).
−
Probe is disconnected or defective.
Hi is
continually
displayed
−
Temperature is above maximum 111°F
(42°C).
−
Probe is short circuited.
Fan(s) or
heater not
operating
−
Verify whether the fan LED is on. If
LED is on, yet fan, actuator or heater is
not operating, verify wiring, fan and
fuse. Refer to Figure 5 for fuse
location. If fuse is blown, replace with
fuse of same type.
Stage 4 Fan,
actuator or
Heater is
operating
erratically
−
Verify that the software setting switch
(position 3) located behind the
faceplate is properly set.
−
Verify the minimum rating (10mA at
230V or 20mA at 230V.
Display is
blank
−
Verify that the line voltage selector
switch is properly set.
−
Verify that the 10 pin flat cable
between the main board and the
faceplate board is connected properly.
www.monitrol.com