1、 Key points for cleaning condenser

The condenser releases heat from the refrigerant to the environment through heat dissipation. If the surface is covered with dust and dirt, it can lead to a decrease in heat dissipation efficiency, resulting in weakened cooling effect, increased energy consumption, and even compressor overload damage. Therefore, regular cleaning of the condenser is crucial.

1. Preparation before cleaning

Power outage and safety protection: Before cleaning, the power supply of the centrifuge must be cut off and a "Do not close" warning sign must be hung to prevent accidental operation from causing electric shock. Operators should wear insulated gloves, goggles, and dust masks to prevent cleaning agents or dirt from splashing into their eyes or respiratory tract.

Equipment shutdown and cooling: If the centrifuge has just finished running, wait for at least 30 minutes until the condenser temperature drops to room temperature before operating to prevent scalding of high-temperature components.

2. Cleaning steps

Surface dust removal:

Use a soft bristled brush or low-pressure compressed air to blow along the direction of the condenser fins to remove surface dust. Avoid direct blowing of high-pressure air to prevent deformation of the fins.

For stubborn dirt, it can be gently wiped with a damp cloth. It is forbidden to use hard objects such as wire brushes and sandpaper to scrape, so as not to damage the surface coating of the fins.

Deep cleaning:

If oil stains or biofilms accumulate between the fins, specialized condenser cleaning agents should be used. After diluting according to the instructions, spray evenly onto the surface of the fins with a spray bottle, let it stand for 10-15 minutes, and after the dirt softens, use a soft bristled brush to scrub along the gaps between the fins.

After cleaning, rinse the fins with clean water until there is no residue of cleaning agent. Finally, dry it with a dry cloth or compressed air.

3. Check after cleaning

Fin integrity: Check the fins for lodging, breakage, or corrosion perforation. Slight lodging can be gently corrected with a fin comb; Serious damage requires contacting the manufacturer to replace the condenser.

Fan operation: After cleaning, start the centrifuge and observe whether the condenser fan is running normally, with no abnormal noise or vibration. If the fan bearings are worn, they need to be replaced in a timely manner.

Heat dissipation effect test: After running the device for 30 minutes, touch the condenser air outlet with your hand and there should be obvious hot air discharge. If the temperature of the air outlet is too low, it may cause poor heat dissipation and the fan needs to be cleaned or checked again.

2、 Key points for refrigerant inspection

Refrigerant is the core medium of the refrigeration cycle in cryogenic centrifuges, and its leakage or insufficient charging can lead to a decrease in refrigeration capacity, and even damage to the compressor. Therefore, it is necessary to regularly check the refrigerant status.

1. Appearance inspection

Pipeline leakage:

Observe whether there are oil stains on the connecting pipelines of components such as condenser, compressor, and dry filter. If oil stains are found, soap water or a leak detector should be used to further confirm the leakage point.

For minor leakage, apply foam water on the pipe connection and observe whether there are bubbles.

Component corrosion: Check for green copper rust or white powder on the surface of copper pipes, especially for equipment used in humid environments. Severe corrosion can cause pipeline perforation, and corroded components need to be replaced in a timely manner.

2. Pressure and temperature detection

High pressure gauge reading:

Start the centrifuge and wait for stable operation before observing the reading on the high-pressure gauge. The normal pressure range varies depending on the type of refrigerant. If the pressure is too high, the condenser may be blocked or the heat dissipation may be poor; Low pressure may result in refrigerant leakage or insufficient charging.

Low pressure gauge reading: The low pressure gauge reading should be lower than the high pressure gauge. If the low pressure is too high, it may cause expansion valve failure or evaporator frosting; Low pressure may result in insufficient refrigerant or clogged dry filters.

Temperature comparison: Use an infrared thermometer to measure the temperature difference between the condenser outlet pipeline and the ambient temperature. The normal temperature difference should be 5-10 ℃. If the temperature difference is too small, there may be insufficient refrigerant or low condenser efficiency; If the temperature difference is too large, there may be air or insufficient subcooling in the system.

3. Refrigerant charging and recovery

Charging volume control:

Refrigerant charging should be carried out according to the charging amount indicated on the equipment nameplate, and excessive or insufficient charging is prohibited. Excessive use can lead to an increase in compressor load and even damage from liquid hammer; Insufficient capacity can lead to a decrease in cooling capacity.

Accurate measurement with an electronic scale is required during filling, and the gas filling method should be used.

Recycling and Environmental Protection: If it is necessary to replace the refrigerant, professional recycling equipment must be used to recycle the old refrigerant into a sealed container, and direct discharge into the atmosphere is prohibited. After recycling, the refrigerant type and purity should be labeled and handed over to qualified units for processing.

3、 Suggested maintenance cycle

Condenser cleaning:

Normal laboratory environment: clean once every 3 months;

Serious dust or biological pollution in the environment: Clean once a month.

Refrigerant inspection:

Check the pressure, temperature, and leakage situation once a year;

If the equipment frequently reports "low pressure protection" or "high pressure protection" faults, the refrigerant should be checked immediately.

4、 Precautions

Do not disassemble on your own: The condenser and refrigeration system involve high-pressure and low-temperature components, and non professionals are prohibited from disassembling or repairing them. Please contact the manufacturer or authorized service provider.

Use original accessories: When replacing refrigerants, dry filters, or sealing rings, the designated model of the equipment must be used to avoid compatibility issues that may cause leaks.

Record maintenance logs: After each cleaning and inspection, it is necessary to record in detail the time, operation content, and problems discovered, in order to track the equipment status and develop maintenance plans.