14
SECTION 9
TROUBLESHOOTING AND
SERVICE
TEMPERATURE
Temperature too high
1/ controller set too high-see SECTION 6.4
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 temperature spikes over
set point and then settles to set
point
recalibrate – see section 6.5
Temperature too low
1/ Controller set too low – see section 6.6
2/ Main control set too low – see section 6.4
3/ unit not recovered from door opening – wait for display to
stop changing
4/ unit not recovered from power failure or being turned off
5/ element failure – see if Heating light is on; compare
current draw to data plate
6/ Main controller failure – confirm with front panel lights
that controller is calling for heat
7/ Controller failure – confirm with front panel lights that
circuit breaker/fuse is operating correctly
8/ wiring problem – check all functions and compare wiring
to wiring schematic in manual - especially around any areas
recently worked on
9/ loose connection – check shadow box for loose
connections
Display reads "LO"
1/ Main sensor is plugged in backwards – reverse sensor
wires to controller
2/ if ambient room temperature is lower than range of unit –
compare set points and ambient temperature to rated
specifications in section 9.0, Unit Specifications
Unit will not heat over a
temperature that is below set point
1/ confirm that Controller set point is set above the Main
Temperature set point and that the reset switch has not
been activated
2/ check connections to sensor