One thing that sometimes comes up in service calls from the field is how to change temperature values from Centigrade to Fahrenheit and vice-versa.

To change temperature values from degrees Centigrade to degrees Fahrenheit, increase the existing Factory Configuration Number (FCN) by 1. For example, if the FCN is 64, change it to 65. Follow these steps in sequence:

  1. Cut power to the controls by turning off the yellow breaker switch located on the control panel. Open the control
  2. panel door and toggle the EPROM switch (located under “CAUTION” on the control board) from OPER to CAL.
  3. Restore power to the control panel with the yellow breaker switch.
  4. The display will read “HIT ANY BUTTON”.
  5. Use the [arrow} and go to “EEPROM DIAGS”, then hit [ENTER}.
  6. Use the [arrow] to go to “SET POINTS MENU”, then hit [ENTER}.
    • Warning! When in “EEPROM DIAGS”, do not hit [ENTER] when the “SET DEFAULT VALUES” is displayed. This will result in the loss of all set points and calibrations!
  7. [Arrow] to “FACTORY CONFIG #”, then hit [ENTER]
  8. Note the number value and increase it by 1 using [Arrow] (you may have to use asterisk [*] to change the increment value). Then hit [ENTER].
  9. Cut power to the controls with the yellow breaker switch.
  10. Switch the EPROM from CAL to OPER.
  11. Restore power to the controls with the yellow breaker switch.
  12. All temperature values will now be in degrees Fahrenheit.

Note

To change from Fahrenheit to Centigrade, simply follow the above sequence, but decrease the FCN by “1”. For example, if the FCN is “65”, change it to “64”. All temperature values will now be in degrees Centigrade.

Recommendation

Whenever a controller is changed from one unit of measure to another, conversion factors and rounding errors can cause a slight degradation in accuracy. Primus recommends that a unit be calibrated after a change in the temperature units.


Have a question or having difficulties? Talk to Dave Schall, our PRIMUS sterilizer expert who is here to assist you anytime at 877.679.7800 extension 1212 or email at dschall@spire-is.com.

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