Van, Truck, Trailer, Bus and Coach Aftermarket News in Ireland

Air conditioning maintenance and repair offers profit opportunities – DENSO says

Almost all modern cars are equipped with air-conditioning, either manual or automatic controlled, representing a real opportunity for workshops to offer competent air-conditioning maintenance and repair.

How do air-conditioning systems work?

DENSO---Fitting-AC-compressor-copyVehicle air-conditioning is designed to provide a comfortable environment for the driver and passengers whatever the weather. The most significant factors related to passenger comfort are temperature, humidity, airflow, radiant heat and clean air.

All car air-conditioners adhere to the same concept and utilise a ‘vapour compression’ refrigeration system. These systems use a refrigerant, when changing phase, to exchange high quantities of heat from the air blown into the car – cooling, heating and dehumidifying the car’s interior.

The refrigerant cycle does have a high and low pressure side and consists of the following four main components: an evaporator, a compressor, a condenser and an expansion device. Two components increase and decrease pressure and temperature, and two components dissipate heat.

Depending on the typical design of a vehicle air-conditioning system, each has either a receiver dryer or accumulator tank.

The basic rule is to replace the receiver dryer or accumulator tank when the system is empty or when the system has been opened.

Different sensors are used to control the air-conditioner either for correct operation or for maintaining the comfortable environment. When a vehicle is equipped with automatic air-conditioning, also referred to as climate control, temperature sensors for ambient and interior temperature – in combination with humidity and solar radiation sensors – are used to maintain a comfortable environment.
To minimise the risk of system failure, which normally means expensive repair, regular operation and annual maintenance are both important. Systems do fail because of different reasons, but the primary reason is insufficient refrigerant.

DENSO-AC-Compressor-duo-with-packagingSM-copyMaintenance is key
Regular maintenance, when performed in the correct way, will avoid issues such as incorrect levels of refrigerant, insufficient heat exchange of condenser and excessive corrosion of aluminium parts.
When performing maintenance, it is important to use the correct tools and equipment and to understand what to check. What’s more, it is very important that equipment is regularly maintained in order to ensure it operates according to specification and cleanliness.

If equipment is not serviced regularly, it is impossible to know the state of the refrigerant inside the machine and this does increase the risk of charging dirty and/or incorrect refrigerant or oil. This would frustrate customers, who may seek compensation for system failure.

Equipment & Tools
A thorough air-conditioning service will take between 45 minutes and one hour using specialist tools and equipment including:
1) Refrigerant gas analyser
2) Sight glass to check state of refrigerant and oil inside
3) Thermometer to read air outlet temperature inside the car when checking system performance.
4) Electronic leak detector
5) Nitrogen pressure test equipment
6) Refrigerant charging equipment.
7) Refrigerant recovery equipment.
8) Oil injection equipment for each type of compressor oil.
9) Flushing equipment to clean refrigerant cycle.
10) Belt tension gauge to confirm correct tension of compressor drive belt.
11) Torque wrench for correct tightening of tubes and hoses.