How to Perform Monthly Maintenance on a Midmark M9®/M11® Steam Sterilizer

Video training guide—how to perform monthly cleaning and maintenance on a Midmark steam sterilizer. Learn more at midmark.com.

This video is an overview of monthly maintenance for your autoclave. However always refer to the appropriate technical documentation for the complete list of instructions, safety alerts and sequence of procedures before conducting any service or maintenance operations. Every 28 days the autoclave automatically displays a "perform monthly maintenance" message. This is a more thorough cleaning of the unit and involves multiple steps. Clean the chamber and plumbing: with a cool chamber drain the autoclaves reservoir and refill with distilled water. Add one ounce of speedclean autoclave cleaner directly to the cool chamber. This is where you load your instruments for sterilization. Run one pouches cycle, but push the stop button when the drying cycle begins. It's not necessary for the dry cycle to run during this maintenance. Drain the reservoir again and refill a second time with clean distilled water for the rinse cycle. Rinse by running one unwrapped cycle. Push the stop button when the drying cycle begins. After the cycle has completed, drain and fill the reservoir with clean distilled water. Then allow the sterilizer to cool. Remove the trays and tray rack, and wipe with a damp cloth. Next remove and clean filters. Remove filters by pulling upward and twisting slightly. Filter should be cleaned by washing with a mild soap and distilled water solution. Use a small stiff brush or an ultrasonic cleaner to remove stubborn deposits. After cleaning rinse the filters with distilled water and set them aside. Wipe the inside of the autoclave chamber being careful not to damage the heating element, steam temperature probe, or water level sensor. Reinsert the filters into the appropriate holes by pushing downward while twisting slightly. Reinstall the tray rack. Next, remove and clean the door and door dam gaskets. Remove the door dam gasket and then the gasket ring from the unit. Clean gaskets and ring with speedclean, distilled water and a soft brush. Inspect the gaskets for damage, shrinking or swelling. Replace the gasket if damage is apparent. Press the door gasket ring into the channel and the door gasket and place the door gasket back into the door. The next part of the required monthly maintenance involves verifying proper operation of the pressure relief valve. Since high pressure and temperature steam will be vented from under the autoclave during this track place a roll towel around the bottom of the autoclave to act as a steam barrier. Press the unwrap cycle and then start. Monitor the display and wait for the pressure to reach 20 PSI. When 20 PSI is reached pull upward firmly on the relief valve lever on top of the autoclave capping and hold it open for three seconds. Steam should discharge freely from beneath the rear of the unit. Release the lever quickly and verify that the valve has closed properly, by noting that steam has stopped escaping. If the unit is still releasing steam pull up on the valve lever again and release it quickly so the valve snaps back into position.
Repeat this if necessary to make sure the valve is seated correctly. Press STOP to cancel the cycle preventing the unit from overheating.
Allow the chamber to cool. If excessive force is required to open the valve or if it will not reseat properly, contact your Midmark authorized dealer. When the maintenance is complete the "perform monthly maintenance" message will go away during your next sterilization cycle. M9 and M11's are designed and tested to provide exceptional reliability throughout their service life. To ensure integrity, performance and safety of all major components, it is the responsibility of the user to have the sterilizer performance and operation verified by Midmark Authorized Service Provider at least every 10 years or 10,000 cycles, whichever comes first. For more detailed information about maintaining your autoclave, please refer to the M9/M11 installation and operation manual. For further support contact Midmark Support Services at 1-800-MIDMARK