- Health Benefits
The dryer / filter element (2 functions in 1 component) is mounted in the air conditioning systems with a TEV valve (Thermal Expansion Valve). The dryer/filter element (hereafter referred to as the dryer) is mounted between the condenser and the TEV. The dryer is often mounted on the condenser. Sometimes the housing is even 1 whole with the condenser.
The refrigerant is passed from the condenser through the dryer in liquid state. The compressor provides the pressure and circulation of the refrigerant in the system. The condenser has previously converted the refrigerant from gaseous to liquid state and can therefore be filtered better.
One of the tasks of the dryer is to remove dirt and moisture from the refrigerant. It is very important to keep the air conditioning system free of moisture. When moisture is present in the system (eg due to a saturated drying element), there is a chance that it will freeze somewhere in the system (eg at the evaporator because that is where it gets coldest). Then there are blockages and the air conditioning no longer cools. As a result, the interior of the car heats up. After the air conditioning has been switched off for fifteen minutes, the evaporator has had time to defrost and the air conditioning will work again for a few minutes.
The drying element is filled with silica gel / silicate granules. These granules contain moisture-absorbing crystals of a silicate. These granules absorb the moisture from the refrigerant as well as possible. The other internal filter elements ensure that the wear and dirt particles remain behind. The dry and clean refrigerant then leaves the dryer via the riser (see picture) and is then fed to the TEV (Thermal Expansion Valve). The TEV is mounted on the evaporator, through which the refrigerant is then passed.
Another job of the dryer is to store refrigerant. Storage allows any gas bubbles to escape, so that the expansion valve receives a constant flow of refrigerant (in liquid form). The pressure waves are flattened in this way. It can be compared to the operation of a accumulator.
The dryer/filter element may become saturated. The drying element (the silica gel / silicate granules) has then absorbed so much moisture that they no longer have an absorbing effect. The moisture is absorbed once and is never released again. When the drying element can no longer function due to the large amount of moisture, we speak of "saturation".
Over time (we are talking about years) there is a chance of saturation. Especially if the air conditioning system has been emptied a number of times and filled with an air conditioning station. Every time the station is connected, or when the system is under construction and pipes are disconnected, a small or large amount of outside air can enter the system. The drying element immediately absorbs all the moisture in the outside air from the air in the air conditioning system. That is why it is wise to replace the filter / dryer element after work on the air conditioning system.
Another cause of saturation can be incorrect installation of the filter/drier element. When a new element is placed, cover caps are placed on it. These caps should only be removed when the relevant pipes of the system are mounted. If these caps are removed and the pipes are not mounted on the dryer until minutes later, the drying element has been exposed to the outside air for too long. It is already a fact that a certain amount of moisture has already penetrated. It is therefore wise to replace the complete filter / dryer element every time the system is emptied and filled.
Compare it to a car oil filter. It is also replaced when the engine oil is changed.
Click here to go to the air conditioning (main) page, where the operation of the whole system with the parts is described.