- Empty and fill system
Every car with air conditioning contains an amount of between 350 and 800 grams of refrigerant. The refrigerant is pumped in gas form by the compressor (1) to the condenser (3). This gives the gas a high pressure (10 – 25 bar).
In the condenser, the gas, which is under high pressure, is cooled by the fan (4). As a result, the gas has become liquid (condensed). It then flows through the dryer/filter element (5). The purpose of this dryer/filter is to filter the impurities that can enter the system as well as water particles from the liquid gas. The gas continues to flow to the expansion valve (8). Here the gas is atomized in the evaporator (6), so that the liquid part changes back into gaseous form.
In the past, the first air conditioning systems were filled with the refrigerant type R12. It later turned out that this was very bad for the environment if it was released through leakage, which is why refrigerant of the type R134a is always used today, which is less harmful to the environment. Old R12 systems may no longer be filled and must therefore be converted to an R134a system during repair. Other hoses and couplings must be fitted here so that the system can be filled with the newer type of refrigerant).
The latest air conditioning systems use the refrigerant type R1234YF. This system will replace R134a in the future. For the time being, new cars are still being produced with this (older) refrigerant.
Emptying and filling the system:
An air-conditioning unit (service station) is required for emptying and filling. This device also checks that the system is free of leaks. After emptying the system, the refrigerant and compressor oil quantities are weighed. This shows how much the system has been drained in recent months or years. A properly functioning system is allowed to drain a maximum of 10% each year.
In the case of leaks, this can of course go much faster. If the air conditioning system never receives maintenance (by this we mean emptying and filling the system), it may be that after a number of years (eg up to 8 years) the air conditioning no longer works. The system is then so empty that it can no longer function properly. This can damage the air conditioning compressor. With any luck, filling the system will be enough to get it working again. It is therefore recommended to have the system maintained every 2 to 4 years. An air conditioning check is therefore not the same as maintenance; sometimes a check only measures the air temperature and concludes whether or not the system is working properly. During maintenance, therefore, ask clearly whether the system will be emptied and filled.