An automotive air conditioner system can be classified into four basic parts - a belt driven pump called a compressor to compress and circulate gas, a radiator like unit called a condenser (removes heat and condenses gas to a liquid), an expansion device, either an orifice tube or a thermal expansion valve (TXV) (dependent on the kind of A/C system used). Systems using orifice tubes also have an accumulator before the compressor to remove moisture from the refrigerant while TXV systems have a receiver-dryer before the evaporator to perform the same crucial task. Both the accumulator and receiver-drier are also used to store refrigerant.

An automotive air conditioning is designed to absorb the heat from the air in the inside of the vehicle and transfer it to the exterior, leaving only cooled or 'conditioned' air behind to be recirculated. Hot air is passed across a gas filled evaporator, where the heat is easily absorbed by the refrigerant (in gas form), effectively removing the heat from the air in the car.

The now heated gas is pulled through the compressor where it is further heated (via compression). The next stage involves the refrigerant being forced through the condenser to quickly extract the heat from the refrigerant. The refrigerant, now condensed to a liquid, then moves through the expansion device (either a TXV or Orifice tube), which regulates the flow of refrigerant going to the evaporator, changing the high-pressure liquid to a low-pressure mist (gas). A fan blowing over the cold fins of the evaporator produces the cold air being blown into the car and the entire process then begins all over again.

A typical air conditioner service may include some of the following items;

• Evaluate air vent temperature
• Check condenser temperature correct
• Assess suction line temperature
• Confirm operation of drive belt & pulley ok
• Ensure correct operation of valves and thermostats
• Condenser fins cleaned
• Ensure good condition of components and hoses
• Evacuation and recharge of refrigerant (where required)
• Test system lines and components for leaks with an electronic leak detector

Avoiding compressor seizure is achieved by checking or changing the oil level in the refrigerant. Should the air filters get choked with dirt and bacteria it will affect the performance of the entire system and it can even cause it to fail to operate completely. Aside from degrading air conditioner performance, dirty air filters can cause all kinds of health problems too.

An air conditioner should be checked for problems annually for any signs of decay in the connections, seals and hoses and ensure there is no reduction of refrigerant over time. Regularly servicing your automotive air conditioner system keeps refrigerant at optimum levels meaning the system does not need to work as hard and this in turn protects the system from damage and reduces the amount of fuel being used up.

An automotive air conditioning is designed to absorb the heat from the air in the inside of the vehicle to the exterior, leaving only cooled or 'conditioned' air behind to be recirculated. This is achieved using a special compound called refrigerant, capable of readily absorbing heat as a gas and quickly losing heat as a liquid.

Being exposed to the elements and very diverse operating conditions and being in use occasionally rather than being 'Always On' can cause issues with the connections, seals and hoses. Your automotive air conditioning system should be examined on a regular basis to ensure there are no problems or refrigerant loss due to failure or leakage from these points.

Simply by cooling the air in your car under normal running conditions, the filters of the air con get dirty and intermittent use can cause seals to dry and crack, allowing them to leak. Even without leaks, the gas in a car air conditioning system will eventually begin to degrade or evaporate over time and should be recharged where required to keep the air con system in peak running condition.

Only qualified mechanics with the appropriate training should attempt to service a car air conditioner. Specific licences are required to be able to service or repair some types of car air conditioning systems, especially where regas (recharging of the refrigerant) is concerned. Strict guidelines and procedures must be adhered to when handling certain refrigerants, which must always be fully recovered and not allowed to escape into the atmosphere during servicing.

Refrigerant can also pose serious health risks if handled incorrectly. Specialist equipment is also required as the air conditioning system is under extreme pressure and must be pulled into a deep vacuum to remove any moisture, to avoid seriously damaging the system. You can find out more about licensing on the Australian Refrigeration Council (ARC) Website.

The evaporator core can be subject to the development of microbes, bacteria and even fungus. This can lead to nasty smells and possibly even be bad for the health of any vehicle occupants. Although modern evaporator units tend to be more efficient, the addition of extra fins leads to an increased ability to trap moisture, allowing micro-organism development.

Woodberry Mechanical Plus mechanics can use specialised ultrasonic technology to eliminate any micro-organisms that may cause bad odours or health issues.

Just ask about our MIST service, which will kill any bacteria that may be lurking in your car's air system. These bacteria can cause odours and even make you sick, especially if you have allergies or asthma. A MIST service doesn't just make your car smell better - it makes it healthier for you and your family.