The role of a condenser
The function of a condenser is to convert the high-temperature, high-pressure gaseous refrigerant sent from the compressor into a liquid refrigerant, and the refrigerant dissipates heat in the condenser to change state. Therefore, a condenser is a heat exchanger that dissipates the heat absorbed by the refrigerant in the vehicle to the atmosphere through the condenser.
Condensers in automobiles are usually installed in front of the car (generally installed in front of the radiator) and cooled by a fan (the condenser fan is generally shared with the radiator fan, and the model uses a dedicated condenser fan)
The structure of a condenser is as the following picture. It consists mainly of pipes and fins, and has a refrigerant inlet and an outlet.Details
Working principles of automobile condensers:
When the refrigerant enters the evaporator, the pressure excitation is reduced, from high pressure gas to low pressure gas. This process absorbs heat, so the evaporator surface temperature is very low, and then the fan can blow the cold air. The condenser will be The high-pressure, high-temperature refrigerant from the compressor is cooled to a high pressure, then cooled at a low temperature and then evaporated through a capillary to evaporate in the evaporator.
Types of automobile condensers
According to the type of cooling medium, the condensers can be classified into four categories, and its function is as following:
In such a condenser, the refrigerant effect of the refrigerant in the other refrigeration system is relied upon to cool the refrigerant vapor on the other side of the heat transfer partition to cause the latter to condense and liquefy, such as the evaporation-condenser in a cascade refrigerator.
2) Air-cooled (also known as air-cooled):
In this type of condenser, the heat released by the refrigerant is carried away by the air. The air can be natural convection, or it can be forced to flow using a fan. This type of condenser is used in places where the Freon refrigeration unit is inconvenient or difficult to supply.
3) Water cooled:
In this type of condenser, the heat released by the refrigerant is carried away by the cooling water. The cooling water can be used once or recycled. Water-cooled condensers can be divided into vertical shell-and-tube type, horizontal shell-and-tube type and casing type according to different structural types.
4) Water-air cooled:
In this type of condenser, the refrigerant is simultaneously cooled by water and air, but mainly relies on the evaporation of cooling water on the surface of the heat transfer tube, and a large amount of heat is taken from the refrigerant side as the latent heat of vaporization of water, and the role of air Mainly to remove water vapor to accelerate the evaporation of water. Therefore, such condensers consume a small amount of water, and are preferred for condensers in areas where air drying, water quality, and water temperature are low and water is not sufficient. Such condensers can be divided into two types, evaporative and leaching, depending on their structural types.
Inspection, disassembly, repair, installation of automobile condensers
1. Common malfunctions of condensers
If the condenser has poor heat dissipation, leakage or blockage, the refrigeration and air conditioning system will be insufficient or not cooled. Common malfunctions of condensers
(1）Condenser fins are dirty, clogged, deformed or damaged;
(2）There is damage, leakage, etc. at the condenser pipe connection
2. Disassembly of the condenser
When the condenser needs to be replaced or needs to be removed for maintenance, disassemble as following:
(1) Discharge refrigerant;
(2) Remove the tubing connected to the condenser and plug the spout with a cloth.
(3) Loosen the condenser fixing bolts and take out the condenser. Care should be taken not to damage the condenser fins when removing the condenser.
3. Inspection and maintenance of condenser
(1) Check the surface of the condenser fins for dirt, if any, brush with a soft brush. Do not flush with steam or high pressure water gun to avoid damaging the condenser heat sink.
(2) Carefully inspect the condenser for paint stripping, deformation, breakage and cracks. If there is damage, crack or deformation, it will affect the sealing performance of the condenser and the normal circulation of the internal refrigerant. The condenser needs to be replaced.
4. Installation of condensers
Install the condenser in the reverse order of removal. After installation, vacuum, replenish the refrigerant and check for leaks.
Automobile condenser temperature is too high
Possible fault location/cause of condenser temperature too high:
1)Poor heat sink 2)Engine water temperature is too high
Condenser overheating maintenance plan or measure:
1) Clean the condenser; Overhaul the condenser and replace if necessary
2) Overhaul or change related accessories
You can find exclusions from the following aspects:
1. Check if the electronic fan is working properly and the air hood is damaged. If there is a problem, there will be no ventilation and heat dissipation when parking.
2. Is the outside of the radiator and the condenser dirty? If it is clean, it will be fine.