2017_E_TYPE-HL.doc Page 45 of 55 24-Oct-2017
This causes the normally closed solenoid valve on the water line to be energized,
spraying water through the misting nozzles to cool the process chamber and oxidizer flue gases.
This water spray action continues until the oxidizer temperature is reduced below the alarm
setting.
If the water spray control system stays on for more than 30 seconds, several conditions
may exist:
1. The nozzles of the OTS system are either partially or completely clogged, thus preventing
a proper water spray from occurring.
2. The deflector pins on the nozzles are bent or broken off which causes a straight stream of
water to be injected into the process chamber. This is not proper, as the OTS spray must
mist to be effective
3. The oven was overloaded with combustible material, which produces combustible fumes
more rapidly than the OTS system can handle.
4. The loading procedures and/or parts processed have been changed or the alarm settings
have been altered on the oven controllers.
5. In case events #3 or #4 occur frequently, a programmable ramp and soak controller may
be installed to control the temperature in the process chamber. This controller will raise
the chamber temperature via a special customized profile or temperature set-point
sequence.
7.3 Testing
Test the process chamber water spray nozzles with the door open so that you can observe
the water spray from the nozzles. Check the system before each cleaning cycle
Activate the OTS spray system by pressing the OTS Test button. This should start the
process chamber water spray mist, which can be confirmed by visual inspection.
7.4 Instrument Synchronization
[For Ovens With Adjustable Burling Switches]
The process indicating control, OTS control, and ETC-P (Excess Temperature Control-
Process) should be synchronized for ETC-P and OTS closes 50
0
F above process chamber set
point.
Note: Programmable controllers - Set OTS and ETC-P 50
0
F above the highest set point
To Next Page
Loading...