1、 Daily cleaning and disinfection
1. Equipment surface and cavity cleaning
Use a soft cloth or vacuum cleaner to clean surface dust and avoid corrosive cleaning agents. After each freeze-drying, it is necessary to wipe the inner wall of the chamber with a dust-free cloth to remove food residues and prevent corrosion or microbial growth. 70% ethanol or specialized disinfectants should be used for disinfection, and food should be disinfected immediately after changing batches.
2. Maintenance of condenser and radiator
Clean the surface dirt of the condenser every six months to ensure heat dissipation efficiency; The radiator needs to be regularly cleaned with a brush vacuum cleaner to prevent ventilation obstruction and overheating.
3. Vacuum pump cleaning
Check the oil quality after each use and replace the oil immediately if turbidity is found, and clean the intake filter membrane (recommended 0.22 μ m PTFE filter membrane).
2、 Key system maintenance
1. Vacuum system maintenance
Sealing inspection: Use a helium mass spectrometer leak detector or vacuum gauge to check the sealing of door seals and valve interfaces every month. Any abnormal fluctuations in vacuum degree (>15Pa) should be repaired in a timely manner.
Vacuum pump oil replacement: Replace the dedicated vacuum pump oil every 300-500 hours of operation or 6 months to ensure pumping efficiency.
2. Maintenance of refrigeration system
Monitor refrigerant pressure monthly (R404A system low pressure 0.2-0.3MPa, high pressure 1.2-1.5MPa), and contact engineers for maintenance in case of abnormalities.
If the ice thickness of the cold trap exceeds 5mm, the automatic defrosting program or manual defrosting (temperature ≤ 50 ℃) should be activated to avoid damage to the equipment caused by excessive ice thickness.
3. Electrical system inspection
Test the grounding safety of the power cord monthly, and calibrate the temperature sensor (with an error of ≤± 1 ℃) and vacuum sensor (with an error of ≤± 5%) every six months.
3、 Safe operation and long-term maintenance
1. Operating standards
Pre frozen material thickness ≤ 15mm, ensuring complete freezing (usually ≤ -50 ℃); The loading capacity shall not exceed 70% of the chamber volume to ensure uniform airflow.
Do not handle materials containing acid, alkali or volatile solvents to avoid equipment corrosion or explosion risks.
2. Management of vulnerable parts
Regularly replace vulnerable parts such as door seals and filters; Reserve key spare parts such as vacuum pump oil and sensors to ensure repair within 24 hours after failure.
3. Long term shutdown maintenance
Disconnect the main power supply and cover it with a dust cover. Perform a monthly power on test run; Restart the refrigeration unit with an interval of ≥ 3 minutes.
4、 Environment and Record Management
1. Environmental requirements: The equipment should be placed in a ventilated area (temperature ≤ 32 ℃, humidity ≤ 80%), away from heat sources and direct sunlight.
2. Maintenance records: Establish a ledger to record maintenance time, content, and replacement parts (such as vacuum pump oil replacement records kept for more than 3 years), for easy fault tracing.
By implementing the above maintenance measures, the lifespan of the equipment can be significantly extended while ensuring the nutritional retention rate of pet food.