How does the air conditioning system on my car work?
There are 5 main parts that make up the system…
The compressor is at the heart of the air conditioning system and is similar in size to an alternator. It is normally sited low down in the engine bay and is connected to the rest of the air conditioning system by 2 hoses. When the air conditioning is turned on inside the vehicle it electrically operates the clutch on the compressor pulley causing refrigerant gas to be pumped through to the rest of the system at a very high pressure. At this point, due to the pressure, the refrigerant gas is very hot.
The condenser is a radiator, normally with one or more of its own electric cooling fans. The condenser cools the high-pressure refrigerant gas, which has come from the compressor and transfers it in to a liquid, expelling the heat in to the atmosphere.
The receiver dryer sits in line with the outlet from the condenser and captures any moisture or contaminates which if left to circulate in the system would cause damage to other air conditioning components.
Next in line is the expansion valve. This part reduces the pressure causing the refrigerant to be reverted back to a gas from a liquid, which causes rapid cooling.
This part is buried deep underneath the dashboard and is where the now highly cooled refrigerant absorbs the heat from inside the vehicle by way of the air being pushed over the outside of the very cold evaporator.
How often should I recharge my cars air con system?
We recommend that you have the system recharged every 2 years. This is in line with most manufacturer recommendations.
Why does it need to be recharged?
Most modern vehicles have an air conditioning or climate control system and that is just as important to maintain as any other system on the vehicle. Around 10-15% of the systems refrigerant can be lost naturally every year. Air conditioning repairs can be costly and largely caused by a lack of regular maintenance i.e. low refrigerant. Low refrigerant can result in the compressor being asked to work much harder than it’s designed to do in order to maintain the required pressure to run the system. Running an air conditioning system with low refrigerant is like running your cars engine with low engine oil, which results in high friction levels and prematurely worn parts.
How much does it cost to recharge the air con system?
Air conditioning recharge/regas – £55 plus VAT.
This involves recovering the refrigerant that remains in the system; a vacuum test and recharge to the vehicle specific refrigerant level including oil if required and UV leak detection dye.