What are the reasons for the lack of heat transfer capacity of the condenser?

1. Dust or scaling on condenser surface

Dust accumulation: When the condenser is cooled by air, dust will accumulate on its surface after long-term operation. Dust is like a layer of insulation, which will hinder the transfer of heat from the refrigerant to the outside air. For example, in the condenser of the air conditioner, if the condenser fins of the outdoor unit are covered with dust, the air cannot smoothly flow through the fins, and the heat exchange efficiency between the air and the refrigerant is reduced.

Scaling: For water-cooled condensers, impurities such as minerals in the water will deposit on the inner surface of the tube wall of the condenser, forming scale. The thermal conductivity of scale is much lower than that of the metal pipe wall, which will greatly increase the thermal resistance. For example, in some water cooling systems using hard water, calcium and magnesium plasma in the water will form hard scale on the tube wall, making it difficult for heat to be transferred to the cooling water through the tube wall, resulting in a decrease in the heat exchange capacity of the condenser.

2. Insufficient cooling medium flow

air-cooled condenser: If the fan fails or the vent is blocked, the cooling air flow will be insufficient. Fan failure may be caused by motor damage, blade deformation and other reasons. The blockage of the vent may be due to the ingress of foreign matter or the accumulation of debris in the surrounding environment. For example, in some air-conditioning condensers installed outdoors, the vents are blocked by leaves, plastic bags and other debris around them, which reduces the amount of air entering the condenser and reduces the heat exchange efficiency.

water-cooled condenser: Water pump failure, pipe blockage or valve not fully open will cause insufficient cooling water flow. Pump failure may be due to mechanical failure or motor problems. Pipeline blockage may be due to the precipitation of impurities in the water or the growth of microorganisms. For example, in an industrial water cooling system, algae in the water blooms and blocks the cooling water pipe, so that the cooling water cannot pass through the condenser at a sufficient flow rate, resulting in a decrease in heat exchange capacity.

3. Abnormal refrigerant flow

Too much or too little refrigerant: Too much refrigerant will cause the liquid level in the condenser to be too high, reducing the effective heat exchange space, causing the refrigerant to not fully transfer heat to the cooling medium. On the contrary, too little refrigerant will make the flow rate of the refrigerant in the condenser too fast, there is not enough time for heat exchange, so that the heat exchange capacity is reduced. For example, in the process of charging the refrigerant in the refrigeration system, if the charging amount exceeds the design requirement, the heat exchange efficiency of the condenser will be affected.

Clogged refrigerant line: The refrigerant may be blocked in the pipeline due to impurities, sludge or ice blockage. The impurities may come from metal chips generated by wear inside the system or foreign bodies remaining during installation. Sludge is formed under certain conditions after the mixing of lubricating oil and refrigerant during the operation of the compressor. Ice blockage is caused by the freezing of moisture in the system at low temperature and low pressure. When the refrigerant pipeline is blocked, the flow of the refrigerant is hindered, which makes the flow and distribution of the refrigerant in the condenser uneven, thereby affecting the heat exchange capacity.

4. The structure of the condenser itself is damaged

Tube bundle rupture or leakage: The tube bundle of the condenser is the main component of the heat exchange between the refrigerant and the cooling medium. If the tube bundle is broken, the refrigerant may leak, which will also affect the normal heat exchange process. For example, under the impact of external force or long-term corrosion, cracks or small holes may appear in the tube bundle, causing the refrigerant to leak into the cooling medium, and reducing the amount of the refrigerant participating in the heat exchange, so that the heat exchange capacity is reduced.

Baffle plate damaged or displaced: The function of the baffle is to guide the cooling medium to flow between the tube bundles and increase the time and area of heat exchange. If the baffles are damaged or dislodged, the cooling medium may take a shortcut and not be able to adequately exchange heat with the refrigerant within the tube bundle. For example, during transportation or installation, the baffle may be impacted and deformed, which affects its guiding effect on the cooling medium, thereby reducing the heat exchange efficiency of the condenser.