Tuttnauer 3870

Asset Type

Sterilizer

Manufacturer

Tuttnauer

Model

3870

Manual Reference

Operation & Maintenance Manual, Tabletop Autoclaves Models 1730, 2340, 2540, 3140, 3850, 3870 M & MK, Cat. No. MAN205-0007000EN, Rev. Q.

Manufacturer Recommendation / AEM Status

Tuttnauer lists maintenance activities at daily, weekly, monthly, 12-month, annual, and cycle-based intervals.

Daily

Clean the door gasket using mild detergent, water, and a soft cloth or sponge. Confirm the gasket is clean and smooth. Before operation, check the reservoir water level and add distilled water when needed.

Weekly

Clean the air jet. Clean and descale the chamber, copper tubes, and reservoir using Chamber Brite. Remove and clean the trays and tray holder with detergent or a non-abrasive stainless-steel cleaner. Lubricate the two door pins, door-tightening bolt screw shaft, and bearing. Clean the exterior with a soft cloth.

Weekly or Every 20 Cycles, Whichever Occurs First

Replace the water in the reservoir.

Monthly

Clean and check the safety valve. The manual recommends having the distilled or mineral-free water quality tested once per month.

Every 12 Months or as Needed

Replace the door gasket.

Annually

Inspect the locking device for excessive wear.

Chamber Brite Interval Clarification

Section 8.1 lists Chamber Brite cleaning once per week. The detailed Chamber Brite procedure also states every 20 cycles or as needed. Because both intervals appear in the manual, follow the more frequent interval or the facility’s documented maintenance policy.

The 3870 requires two packets of Chamber Brite per cleaning procedure. The listed cleaning cycle for an M-series autoclave is 30 minutes at 273°F/134°C from a cold start, without a drying cycle.

Manufacturer-Listed Replacement Items

Door gasket: Replace every 12 months or as needed.

Door gasket part number: Not specified in the provided manual.

Electrical Safety and Calibration Status

The provided operation and maintenance manual does not list a recurring electrical safety testing interval, ground resistance or leakage-current limits, a pressure-gauge calibration interval, a thermostat calibration interval, or a manufacturer PM test form with calibration tolerances.

The unit is intended to be connected to a properly grounded outlet protected by an earth-leakage device or GFI. Electrical safety testing should be completed and documented when required by facility policy.

If a facility performs this PM at a different interval or changes the listed activities, that should be handled under the facility’s approved AEM program, risk assessment, maintenance history, and applicable regulatory requirements.

What This PM Procedure Covers

• Visual and mechanical inspection
• Door, gasket, locking mechanism, and safety-device inspection
• Chamber, reservoir, air-jet, tray, and piping maintenance
• Safety-valve functional check
• Water-quality and reservoir maintenance review
• Functional sterilization-cycle check
• Facility-policy electrical safety testing
• PM documentation and return-to-service determination

Required Tools and Equipment

• Mild detergent
• Soft cloth or non-abrasive sponge
• Non-abrasive stainless-steel cleaner
• Distilled or mineral-free water
• Two packets of Tuttnauer Chamber Brite
• Silicone reservoir drain hose supplied with the autoclave
• Drain bucket
• Light machine oil, such as 3-in-1 oil, or white lithium grease
• Screwdriver, hook, or similar tool for operating the safety-valve ring
• Heat-resistant gloves and appropriate PPE
• Biological and chemical indicators when included under facility sterilization-monitoring policy
• Electrical safety analyzer when required by facility policy

Step-by-Step PM Procedure

1. Remove the Sterilizer from Service

Action

• Confirm the chamber pressure gauge reads 0 psi.
• Turn the main power switch off.
• Disconnect the power cord before cleaning, draining, or mechanical inspection.
• Allow the chamber and internal components to cool.

Expected Outcome

The unit is electrically isolated, depressurized, and cool enough to service safely.

2. Inspect the Exterior and Installation

Action

Inspect the cabinet and control panel, power cord, plug, rear power inlet, main switch, pressure gauge, timer and thermostat knobs, multipurpose valve and knob, indicator lights, feet, countertop stability, and rear and right-side ventilation clearance.

Confirm the sterilizer is level and positioned on a rigid surface capable of supporting the unit and load.

Expected Outcome

No damaged, loose, burned, cracked, corroded, or missing components are present.

3. Inspect and Clean the Door Gasket

Action

• Inspect the gasket for cracks, cuts, flattening, stiffness, contamination, or steam-leak tracks.
• Clean it with mild detergent, water, and a soft cloth or sponge.
• Verify the gasket remains smooth.
• Replace the gasket if it is 12 months old, damaged, or no longer seals correctly.
• When installing a replacement gasket, position the widest side of its trapezoidal cross-section toward the door.

Expected Outcome

The gasket is clean, flexible, undamaged, correctly installed, and capable of sealing the chamber.

4. Inspect the Door and Locking Mechanism

Action

Inspect the door closing device, tightening bolt and threads, two door pins, door microswitch and actuator, pressure-locking bellows mechanism, door alignment, and locking components for excessive wear.

Apply a few drops of oil to the two door pins, door-tightening bolt screw shaft, and closing-device bearing.

Do not overtighten the door. The manual instructs that it be tightened only hand-tight unless additional tightening is needed to obtain a complete seal.

Expected Outcome

The door closes smoothly, activates the microswitch, locks securely under pressure, and shows no excessive wear.

5. Remove and Clean the Trays and Tray Holder

Action

• Remove both trays and the tray holder.
• Clean them with detergent or a non-abrasive stainless-steel cleaner and water.
• Rinse immediately to prevent staining.
• Inspect for distortion, corrosion, sharp edges, or damage.

The manual lists the following 3870 tray components:

• Large tray: Cat. No. CC520010
• Small tray: Cat. No. CC520020
• Tray holder: Cat. No. CC510010

Expected Outcome

Trays and holder are clean, undamaged, and securely supported.

6. Drain and Flush the Reservoir

Action

• Confirm the power cord is disconnected and chamber pressure is zero.
• Connect the supplied silicone hose to the drain valve and route it into a bucket.
• Turn the drain valve counterclockwise to open.
• Fully drain the reservoir.
• Flush the reservoir with approximately one quart of tap water.
• Close the drain valve clockwise.
• Inspect the drain valve for leakage.
• Refill with distilled water to just below the safety-valve holder.

Do not fill above the base of the safety-valve holder.

Expected Outcome

The reservoir drains freely, the drain valve seals, and the reservoir contains clean distilled water at the correct level.

7. Clean the Air Jet

Action

• Remove the reservoir cover.
• Locate the air jet and its permanently installed cleanout wire.
• Move the wire back and forth through the jet opening ten times.
• Inspect for visible debris or mineral deposits.

The manual identifies a dirty air jet as a primary cause of incomplete air removal, failed spore tests, and chemical indicators that do not change correctly.

Expected Outcome

The air-jet opening is clear and the cleanout wire moves freely.

8. Clean and Descale with Chamber Brite

Action

• Confirm the chamber is cold and empty.
• Remove the trays and instruments.
• Spread two packets of Chamber Brite in an even line along the chamber bottom from back to front.
• Add the proper cycle water.
• Run a cold-start sterilization cycle at 273°F/134°C for 30 minutes without drying.
• Exhaust the sterilizer.
• Drain the reservoir.
• Refill the reservoir with distilled water.
• Run a second 30-minute sterilization cycle without Chamber Brite and without drying.
• Exhaust and drain the reservoir again.
• Turn the sterilizer off and allow it to cool.
• Wipe the chamber interior and tray holder with a damp cloth.
• Refill the reservoir with distilled water.
• Briefly place the multipurpose valve in FILL WATER to admit approximately 2–4 ounces into the chamber, then remove that water.

Do not process instruments during the cleaning procedure.

Do not use bleach, steel wool, steel brushes, or abrasive cleaning materials.

Expected Outcome

The chamber, reservoir, copper tubing, and associated piping are clean and free of visible deposits and Chamber Brite residue.

9. Check the Chamber Pitch and Fill Level

Action

• With the chamber empty, place 24–27 ounces, or 720–810 mL, of distilled water into the 3870 chamber.
• Confirm the water covers the chamber bottom to within approximately ½ inch of the front groove.
• Adjust the front feet only if needed to obtain the correct water position.

Expected Outcome

The chamber pitch allows the correct quantity of water to cover the chamber bottom without excessive or insufficient fill.

10. Perform the Monthly Safety-Valve Check

Action

Use heat-resistant PPE and keep your face and hands away from escaping steam.

• Run a sterilization cycle at 273°F/134°C.
• Allow chamber pressure to reach approximately 30 psi, identified in the manual as approximately 260 kPa.
• Return the timer to 0 minutes.
• Remove the reservoir cover.
• Using a screwdriver, hook, or similar tool, pull the safety-valve ring.
• Hold the valve open for approximately two seconds and release it.
• Verify steam is released and the valve closes immediately.
• Turn the multipurpose valve to EXH/DRY after a successful check.
• Wait until chamber pressure returns to 0 psi before opening the door.

If the valve remains stuck open, allow pressure to fall to zero, operate the valve ring, and repeat the check. If it sticks open again, remove the sterilizer from service and arrange repair.

Expected Outcome

The valve releases steam when operated and reseats immediately without continued leakage.

11. Perform a Functional Cycle

Action

• Confirm the reservoir contains distilled water.
• Set the pressure-gauge tracking needle to 0 psi.
• Place the multipurpose valve in FILL WATER.
• Fill the chamber to the proper water level.
• Return the valve to STERILIZE.
• Close and hand-tighten the door.
• Select the applicable temperature and cycle time.
• Observe the power, heat, and dry indicator operation.
• Confirm pressure rises steadily.
• Confirm the heat indicator cycles as the selected operating point is maintained.
• Confirm the timer counts down and the buzzer sounds at completion.
• Turn the multipurpose valve promptly to EXH/DRY.
• Confirm pressure returns to 0 psi.
• Confirm the door remains locked while pressure is present and can be opened after pressure reaches zero.

For a 3870 M cold-start cycle, the manual lists:

• Unwrapped instruments at 273°F/134°C: 32 minutes
• Wrapped instruments at 273°F/134°C: 36 minutes
• Packs at 273°F/134°C: 45 minutes
• Lower-temperature cycle at 250°F/121°C: 60 minutes

These are total sterilization-cycle timer settings and do not include drying.

Expected Outcome

The sterilizer heats, pressurizes, controls, times, exhausts, dries, and releases the door normally without steam or water leakage.

12. Verify Sterilization Monitoring

Action

When required by facility infection-prevention policy:

• Verify chemical indicators respond appropriately during the cycle.
• Review biological-indicator testing records.
• Confirm failed indicator or spore-test results have been investigated.

The manual states that a biological spore test should be used at least weekly, while noting that testing standards may vary.

Expected Outcome

Sterilization-monitoring results comply with the facility’s approved policy.

13. Final Inspection

Action

Inspect for door-gasket leakage, safety-valve leakage, steam escaping from the closing-device area, water leakage from the drain valve, water spilling when the door opens, abnormal noise, odor, overheating, or electrical operation, failure of pressure to rise or return to zero, and failure of the door interlock.

Reinstall the trays and tray holder after all cleaning residue has been removed.

Expected Outcome

The sterilizer is clean, complete, leak-free, and operating normally.

Electrical Safety Testing

The provided manual does not state a recurring electrical safety test interval or manufacturer-specific acceptance limits.

Perform electrical safety testing when required by facility policy, after applicable electrical repairs, or under the facility’s approved AEM program.

Ground Resistance

Ground resistance measured in ohms, expected ≤ 0.5 Ω or facility/NFPA 99 criteria if different:

Result =

Leakage Current

Touch/chassis leakage measured in microamps:

Facility limit used =

Result =

Pass / Fail =

Additional Electrical Inspection

Protective ground present at the supply outlet: Pass / Fail

Power cord and plug condition: Pass / Fail

GFI or earth-leakage protection present as required by installation policy: Pass / Fail

Pass / Fail Criteria

Pass

The sterilizer passes PM when:

• Chamber, reservoir, trays, piping, and air jet are clean.
• Door gasket and locking mechanism are serviceable.
• Safety valve releases steam and reseats immediately.
• Chamber fills with the correct water quantity.
• Unit heats, pressurizes, controls, times, exhausts, and dries normally.
• Door remains locked while pressure is present.
• No steam, water, or electrical leakage is observed.
• Required electrical safety results meet the facility’s documented limits.
• Required chemical or biological monitoring results are acceptable.

Remove from Service

Remove the sterilizer from service when:

• The safety valve remains stuck open, fails to release, or continues leaking.
• The door opens or can be released while chamber pressure is present.
• The door bellows or locking device is damaged or excessively worn.
• The chamber, door, or pressure-retaining components are damaged.
• The unit overheats or repeatedly trips the cutout thermostat.
• The unit does not achieve or maintain normal operating pressure.
• Steam leakage cannot be corrected by proper door closure or gasket replacement.
• Chemical or biological monitoring fails and the cause has not been corrected.
• Electrical safety testing fails.
• The power cord, plug, grounding connection, or enclosure is unsafe.

Use the manufacturer service manual, facility policy, and approved AEM program to determine the final PM interval and return-to-service requirements.