Mechanical, Other – Shellab SGO3-2 User Manual
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1/ ±0.1 may be normal.
2/ For G suffix models: may vary ±2.0 degrees.
3/ For F suffix models: is fan working?
–verify movement of air in
chamber.
4/ Is ambient room temperature radically changing
– either door
opening or room airflow from heaters or air conditioning ?
– stabilize
ambient conditions.
5/ This may happen if exhaust stack is 100% open or if power exhaust
is cycling
– adjust stack to at least ¼ closed.
6/ Sensor miss-located, damaged or wires may be damaged - check
mounts for control and OTP sensors, then trace wires or tubing
between sensors and controls.
7/ Calibration sensitivity
– call Customer Service.
8/ High limit set too low
– be sure that Safety Thermostat is set more
than 5 degrees over Main Controller set point; check if OTP pilot is on
continuously; turn controller knob completely clockwise to see if
problem solved then follow instructions in section 6.5 for correct setting.
9/ Electrical noise
– remove nearby sources of RFI including motors,
arcing relays or radio transmitters
10/ 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.
11/ 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.
Will not maintain set point
1/ Assure that set point is at least 5 degrees over ambient.
2/ See if ambient is fluctuating; check for adjacent open doors or
HVAC duct openings
– stabilize ambient conditions.
Display and reference thermometer don’t
match
1/ Calibration error
– see section 6.4.
2/ Temperature sensor failure
– call Customer Service.
3/ Controller failure
– call Customer Service.
4/ Allow at least two hours to stabilize.
5/ Verify that reference thermometer is certified.
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. For maximum accuracy, calibration should be done at or as
close to the set point temperature.
MECHANICAL
Motor doesn't move; F suffix models
1/ If shaft spins freely: check connections to motor and check voltage to
motor.
2/ If shaft rubs or is frozen, relieve binding and retest.
Motor makes noise; F suffix models
1/ If noise is from the motor, tap the top of motor shaft with ball peen
hammer.
2/ If the sound gets worse, tap the other end of the shaft
– avoiding
touching the blower wheel.
3/ If there is no change, call Customer Service.
Door not sealing
1/ Adjust hinge blocks or twist the door.
2/ Confirm that unit has not been damaged and body is not square.
3/ Check physical condition of gasket for tears or punctures.
OTHER