Instruction manual

-6-
Electric Heat Treat Furnace Start-Up Procedure
MIFCO Heat Treat Furnaces are very easy to operate. They have been thoroughly tested and
calibrated at the factory. The following steps will get the furnace running and if you refer to the easy,
one page start-up guides for your particular instrument, the setpoints and programs can be entered.
Included in this manual are the instrument manuals for your particular furnace, from the
manufacturer.
Start-Up
1. Press the start button or flip the toggle switch to on. The instrument will go through a brief self
diagnostic and then display the current temperature. If the furnace has a separate cooling unit for the
water cooled bearing, be sure to turn it on also.
2. If there is a circulating fan bypass switch for cooling the high temperature chamber, make sure that
it is in the off position. This will insure that when the door is opened while the chamber is in operation,
the fan will shut off to prevent accidents.
3. Enter a setpoint into the controlling instrument, per instructions for that instrument on the
following pages.
4. If there is a high limit instrument, there must also be a setpoint entered into it that is 25 to 30 degrees
higher than the controlling instrument setpoint. This can also be left at its maximum temperature setting
(default setting from the factory). The primary purpose of the high limit instrument is to protect the
heating panels from overheating in the event of a problem with the main temperature controller. That is
why the default is set to the chamber maximum setpoint at the factory. The secondary purpose of the
high limit is to protect parts being processed from going over a maximum setpoint, as a backup to the
main temperature controller.
5. The chamber should proceed to the setpoint and hold at temperature with no further adjustments.
Shut-Down
1. Turn the setpoint on the controlling instrument down to 100° or less and open the chamber door.
Allow the furnace to run until the chamber falls below 200° F. This will protect the bearings on the fan
shaft. In the low temperature chambers that contain stainless work chambers, the fan will continue to
run automatically with the door open. On chambers with a safety cutoff for the fan, there will be a
bypass switch for the circulating fan on the control panel. Turn this switch on so that the chamber will
cool faster. Failure to follow this procedure will reduce the life of the bearings on the fan shaft and they
will not_ be replaced under the machine warranty.