Key scenarios that require professional maintenance

The refrigeration efficiency has significantly decreased

Performance: Prolonged pre freezing time, slow recovery of cold trap temperature, unstable vacuum degree.

Possible reasons: refrigerant leakage, compressor wear, heat exchanger scaling.

Maintenance: Leak detection and repair, refrigerant replenishment/replacement, cleaning of heat exchange components.

Abnormal noise or vibration

Performance: The compressor produces abnormal noise during operation and the overall vibration of the equipment intensifies.

Possible reasons: loose components, worn bearings, improper refrigerant charging.

Maintenance: Tighten screws, replace worn parts, and re adjust refrigerant charging amount.

Restart after long-term disuse

Scenario: Before the equipment is restarted after being shut down for more than 3 months.

Maintenance: Check the insulation of the circuit, test the starting performance of the compressor, and replace the dry filter (to avoid moisture).

When the environmental conditions are harsh

Scenario: The device operates in an environment with high levels of dust, humidity, or temperatures exceeding 30 ℃.

The maintenance cycle has been shortened to once every 3 months, with a focus on cleaning the condenser dust and checking the moisture resistance of the electrical system.

3、 Core projects of professional maintenance

Compressor system

Check the quality of the compressor oil. If there is excessive emulsification or impurities, replace the lubricating oil.

Check the sealing of the air valve, and if it is severely worn, grind or replace the components.

Test the insulation resistance of the motor to ensure safe operation.

Refrigerant circulation system

Analyze the purity of the refrigerant and eliminate impurities such as moisture and air (purification or replacement is required when the purity is below 98%).

Replace the dry filter (usually once a year, more frequently in humid environments).

Pressure test: Check whether the high and low pressure sides meet the design parameters and identify leakage points.

Heat exchanger (condenser/evaporator)

Clean the dust and debris on the surface of the condenser (especially for air-cooled equipment) to ensure heat dissipation efficiency.

Remove frost buildup on the surface of the evaporator (if using a coil evaporator) to avoid affecting heat exchange.

Control system and sensors

Calibrate temperature sensors (cold trap, material temperature probe), and adjust if the error exceeds ± 0.5 ℃.

Test the response sensitivity of components such as pressure controllers and solenoid valves to ensure the normal functioning of automatic control.

4、 Maintenance precautions

Operated by professionals

The refrigeration system involves high-pressure components and special refrigerants (such as R404A, R23), which may cause safety accidents or equipment damage to non professionals.

Record and maintain archives

Save information such as maintenance time, project, and replacement part model for easy traceability of equipment status.

Prioritize following the manufacturer's recommendations

The maintenance cycle of different brands of equipment (such as Thermo Fisher, Dongfeng, LABCONCO, etc.) may vary greatly, and it is necessary to refer to the manual or consult the after-sales engineer.

5、 Daily recommendations for extending the lifespan of refrigeration systems

Avoid frequent start stop: Wait at least 5 minutes after each shutdown before restarting to reduce compressor load.

Keep the environment clean: Regularly clean up the debris around the equipment to ensure good ventilation (air-cooled equipment needs to reserve ≥ 30cm of heat dissipation space).

Monitoring operating parameters: Daily recording of cold trap temperature, vacuum degree, compressor current and other data, and timely shutdown for troubleshooting in case of abnormalities.