Shellab SCO26H-2 - Manual (Page 13)

4/ is the Over Temp Limit Thermostat set high enough? – for diagnostics, should
be turned fully CCW 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 fan working?
– remove top panel and verify movement of cooling fan in
center of shadow box
3/ is ambient radically changing
– either door opening or room airflow from
heaters or air conditioning? – stabilize ambient conditions
4/ sensor miss-located, damaged or wires may be damaged - check mounts for
control and Over Temp Limit Thermostat sensors, then trace wires or tubing
between sensors and controls
5/ calibration sensitivity
– call Customer Service
6/ high limit set too low – be sure that Safety is more than 5 degrees over
desired set point; check if Over Temp Limit pilot light is on continuously; turn
controller knob completely clock-wise to see if problem solved then follow
instructions in section 6.4
7/ electrical noise
– remove nearby sources of RFI including motors, arcing
relays or radio transmitters
8/ bad connection on temperature sensor or faulty sensor
– check connectors
for continuity and mechanical soundness while watching display for erratic
behavior; check sensor and wiring for mechanical damage
9/ bad connections or faulty solid state relay
– check connectors for mechanical
soundness and look for corrosion around terminals or signs of arcing or other
visible deterioration
10/ Water jacket empty or low
– check indicator warning light or water level at fill
port in back of unit.
11/ Peltier condensate collector failure
Will not maintain set point
1/ assure that set point is at least 5 degrees over ambient
2/ see if ambient is fluctuating
Display and actual (from reference
thermometer) don’t match
1/ calibration error – see operator’s manual
2/ temperature sensor failure – evaluate if pilot light is operating correctly
3/ controller failure – evaluate if pilot light is operating correctly
4/ allow at least two hours to stabilize
5/ see if reference thermometer is certified
Reference thermometer does not match
digital display
See Temp Calibration in Section 10
Can't adjust set points or calibration
1/ turn entire unit off and on to reset
2/ if repeatedly happens, call Customer Service
Calibrated at one temperature, but not
at another
This can be a normal condition when operating temperature varies widely, e.g.,
>30C° difference between setpoints. For maximum accuracy, calibration should
be done at close to the set point temperature.
HUMIDITY LEVEL
Can't achieve rated humidity/temp
1/ relative humidity sensor or controller failure
2/ check for bad door seal
3/ check for leaking water around steamer
4/ confirm a sufficient and distilled water source
5/ calibrate humidity sensor with independent reference
6/ assure that pressure relief valve is closed
7/ assure that steamer is working (see Humidity Section-4)
Can't adjust set points or calibration
1/ confirm all wire connections
2/ confirm software revision
3/ call Customer Service
Steam generator not working
1/ check if fill solenoid, injection valve, relief valve, float switch and relays are
working
– see schematic in manual
2/ check for water leaks around steamer