1. Maintenance cycles and core tasks
Routine maintenance (after each experiment)
· Main tasks: Clean glass components; wipe instrument surfaces; check system tightness.
· Key points and operations:
· Glass components: Rinse immediately with clean water after use, clean with a soft-bristled brush, and let dry for future use. The frosted joints can be cleaned with ethanol and a small amount of vacuum grease can be applied.
· Instrument surface: Wipe with a soft cloth dampened with water or ethanol to remove solvents and stains.
· Tightness inspection: Clamp the vacuum tube and observe whether the vacuum gauge reading remains stable, making a preliminary judgment on whether there is any air leakage.
Weekly maintenance
· Main tasks: Replace the heating pot medium; clean the glass ground joint and apply vacuum grease.
· Key points and operations:
· Heating pot: Drain and replace with deionized water or silicone oil to prevent scale buildup or degradation of the medium.
· Glass joint: Remove it, clean the ground joint with ethanol, and reapply a thin layer of vacuum grease.
monthly maintenance
Main tasks: Replace the bath solution in the water bath; clean the condenser tube.
· Key points and operations:
· Water bath: It is recommended to replace the bath liquid once a month to prevent scale buildup from affecting heating. If deionized water is used, 0.1g of sodium carbonate can be added per liter to prevent rust.
· Condenser tube: If the inner wall turns yellow and forms scale, it can be soaked and cleaned with 20%-25% dilute hydrochloric acid.
Quarterly maintenance
Main tasks: Inspect and clean the sealing ring; inspect mechanical components.
· Key points and operations:
· Seal ring: Disassemble and inspect for aging, wear, or debris embedded. Clean the groove with a soft cloth dipped in alcohol, apply vacuum grease after it dries, and reinstall. Typically, it needs to be inspected and replaced every 3-6 months.
· Mechanical components: Check whether the rotating spindle operates smoothly; listen for any abnormal noise from the motor, and contact a professional for lubrication if necessary.
II. Long-term maintenance for deactivation
If the instrument needs to be stored for an extended period (such as during the holidays), it is recommended to follow the steps below:
1. Thorough cleaning: Empty and clean all glass components, evaporation flasks, and collection flasks, ensuring they are completely dried.
2. Drain the liquid: Drain all the medium from the water bath and the cooling circulator.
3. Protecting the vacuum pump: This is a crucial step. For diaphragm vacuum pumps, a small amount of anhydrous ethanol or acetone should be injected into the inlet before shutdown and run for a few minutes to clean the internal piping and diaphragm, followed by pumping in air to dry it. Allowing the pump to continue pumping air for 15-20 minutes after the experiment can also help expel condensed solvents.
4. Storage with power off: Turn off all power sources, place the instrument in a dry, ventilated environment free from corrosive gases, and cover it with a dustproof cover.
III. Common Fault Troubleshooting
When encountering problems, you can refer to the following list for preliminary diagnosis:
• Insufficient vacuum degree/slow distillation speed
Possible causes: system air leakage; vacuum pump malfunction; aging of sealing ring.
· Solution steps:
1. Check all glass joints and vacuum pipelines for tight connections and cracks.
2. Inspect and clean the sealing ring, and replace it if necessary.
3. Check whether the vacuum pump is working properly.
• The motor does not rotate
Possible causes: power supply issue; transportation lock not released; belt aging or broken; circuit fault.
· Solution steps:
1. Check the power plug and switch.
2. Check whether it is an electric lift model. If it is, unlock the transportation lock.
3. Contact a professional to inspect the belt and internal circuitry.
• The water bath is not heating up
Possible reasons: power supply is not connected; heating coil is damaged; temperature controller is faulty.
· Solution steps:
1. Confirm that the power supply is normal and the bath pot has been filled with medium.
2. Check the display and indicator lights of the temperature controller.
3. Contact after-sales service to inspect the heating coil or temperature control components.
• Adhesion of glass ground edge
Possible reasons: Long-term non-use or dried-up vacuum grease.
· Solution steps:
1. Do not twist hard. Gently tap the connection with a wooden tool.
2. Apply moderate heat to the adhered area and utilize thermal expansion for separation.
3. Place the entire assembly into the ultrasonic cleaning machine for indirect ultrasonic exposure.
IV. Key points for operation and storage
· Operation: Ensure that the temperature of the heating pot is at least 25°C below the flash point of the solvent. When the instrument is operating, do not touch the rotating parts and the heating pot. The volume of distilled material should not exceed half of the evaporation flask.
Environmental requirements: Place the instrument on a stable, vibration-free surface. Ensure the environment is dry to prevent moisture from affecting the electrical components.
Rotary evaporators of different brands and models may vary, so the preferred step before carrying out any maintenance is to refer to the official instruction manual that comes with your equipment.