Despatch RFD Series - Manual (Page 38)

T ROUBLESHOOTING
RFD Oven Series Owner’s Manual
38 Version 1
Copyright © 2012 by Despatch Industries.
All rights reserved. No part of the contents of this manual may be reproduced, copied or transmitted in any form or by any
means including graphic, electronic, or mechanical methods or photocopying, recording, or information storage and
retrieval systems without the written permission of Despatch Industries, unless for purchaser's personal use.
Difficulty Probable Cause Suggested Remedy
on fan shaft wheel and inlet ring
Unbalanced fan wheel Replace fan wheel
Excessive vibration
Dirty fan wheel Clean fan
Unbalanced fan wheel Replace fan wheel
Oven will not
control at setpoint
High Limit set too low
Set the High Limit higher.
Protocol 3 controller
malfunction
Replace controller
SCR malfunction
Replace SCR and/or check control output
voltage.
Air friction of recirculation
fan Open exhaust air vent. Unit will not control
below minimum operating temperature with
vent closed.
Heater does not
shut down until
temperature
reaches the High
Limit setting
Protocol 3 controller
malfunction Replace controller.
SCR malfunction Replace SCR
Danger!
Electrical panels contain high voltage. Disconnect and lock out the
power supply before working inside any electrical panels. Failure to
lock out the power supply can result in death or injury.
7.2. Troubleshoot Airflow Conditions
Table 4 lists possible problems and remedies for airflow conditions.
Table 4. Airflow Troubleshooting.
Conditions Actions
A. Non-uniform work
chamber 1. Check to get a lightly positive chamber pressure by closing down
exhaust or opening up fresh air.
a. Review damper instructions (Section 3.2)
b. Adjust optional supply louvers:
i. Open for cold spots
ii. Close for hot spots
c. If necessary, adjust optional return louvers in the same
manner.