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the final location for the oven. However, it may be a receiving dock, some well
ventilated space or even outside if the weather is acceptable. If this location is a very
clean area, then special attention must be given to an exhaust hook-up that will capture
the smoke and odor.
The following procedure is recommended:
1.
Locate the equipment exhaust opening where chamber air is being expelled.
If the oven filter is burned off in a clean area, be sure to handle the equipment
exhaust appropriately. If the equipment is large and the exhaust stack is a
permanent service connection, it should be connected before the burn-off
process is run. If the equipment is small with no permanent exhaust duct
required, arrange a temporary connection out of the clean area that will handle
the maximum temperature of the equipment. Direct the smoke and odor outside,
or to a highly ventilated area.
2.
Filters for 260 C/500 F and below: Set the temperature control at the maximum
process temperature.
Filters for above 260 C/500 F: To maximize the life of the filter, set the control to
ramp the oven temperature at 1 C (1.8 F) per minute or slower. Program a 3
hour soak at 75 C/167 F, and a 3.5 hour soak at 105 C/220 F during the first
heating ramp. The limited ramp rate and soaks will cure the ceramic adhesive in
these filters for maximum strength.
3.
Start the fan after making the electrical power connections.
4.
Energize the equipment heater.
Use enough fresh air or purge nitrogen to remove the smoke, while still being
able to achieve and maintain the necessary temperature. The completion of the
burn-off period should be based on the particle level in the oven or smoke-free
exhaust and minimal odor level.
The filter hold-down nuts should be checked after burn-off and tightened again if
necessary. For best oven particle control, this step should be repeated on a regular
basis.
