Despatch DES2000 Controller - Manual (Page 18)

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Table 8 Difficulties, Probable Causes, and Remedies
Difficulty Probable cause Suggested Remedy
Failure to heat CONTROL instrument
malfunction Check parameter in controller or replace
controller if OUT LED on controller does not turn
on.
Erratic
temperature CONTROL instrument
malfunction Check control parameters before replacing the
CONTROL instrument.
Inaccurate
temperature CONTROL instrument
miscalibration Recalibrate CONTROL instrument.
Oven will not
control at
setpoint HI-LIMIT instrument set
too low Set the HI-LIMIT higher.
CONTROL instrument
malfunction Check control parameters before replacing
CONTROL instrument.
Air friction of recirculation
fan Open exhaust air vent. Unit will not control at
minimum operating temperature with vent(s)
closed.
Heater does
not shutdown
until temp.
reaches the
HI-LIMIT
setting CONTROL instrument
malfunction Verify control parameters. Replace relay if no
output exists. Replace CONTROL instrument if
5VDC output exists.
SSR Relay malfunction Replace relay if no CONTROL output exists.