Troubleshooting, Temperature – Shellab SMO38HP-2 User Manual
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TROUBLESHOOTING
TEMPERATURE
Temperature too high
1/ controller set too high
2/ controller failed on
– call Customer Service
3/ wiring error
– call Customer Service
Display reads "HI" or "400"+
Probe is unplugged, is broken or wire to sensor is broken
– trace wire
from display to probe; move wire and watch display to see intermittent
problems
Chamber temp spikes over set point and
then settles to set point
Recalibrate
Temperature too low
1/ high limit set too low
– see section 4.5
2/ controller set too low
3/ unit not recovered from door opening
– wait for display to stop changing
4/ unit not recovered from power failure or being turned off
– incubators
will need 24 hours to warm up and stabilize
5/ element failure
– call Customer Service
6/ controller failure
– confirm with front panel lights that controller is calling
for heat
7/ high limit failure
– confirm with front panel lights that High Limit is
operating correctly
8/ wiring problem
– check all functions and compare wiring to owners
manual - especially around any areas recently worked on
9/ loose connection
– check shadow box for loose connections
Display reads "LO"
1/ sensor is plugged in backwards
– call Customer Service
2/ if ambient room temperature is lower than range of unit
– compare set
points and ambient temperature to rated specifications in Section 10.0
Unit will not heat over a temperature that
is below set point
1/ confirm that blower motor is moving and that amperage and voltage
match data plate
– check blower motor motion in shadow box and feel for
air movement in chamber
2/ confirm that set point is set high enough
–turn High Limit clockwise and
see if High Limit light comes on
3/ check connections to sensor
4/ check calibration
– using independent reference thermometer.
Unit will heat up at all
1/ verify that controller is asking for heat by looking for controller light
– if
controller light is not on, there is a problem with the controller
2/check amperage
– amperage should be virtually at maximum rated
(data plate) amperage
3/ do all controller functions work?
4/ is the High Limit set high enough?
– for diagnostics, should be fully
clockwise with the pilot light never on
5/ HAS THE FUSE/CIRCUIT BREAKER BLOWN?
Indicated chamber temperature unstable
1/ ±0.1 may be normal
2/ is blower motor working?
– remove top panel and verify movement of
Section
8