Delphi offers useful tips to help drivers enhance fuel economy during A/C use

The use of any commercial vehicle's air conditioning system increases the load on a vehicle's engine, which in turn consumes fuel
. The National Renewable Energy Laboratories (NREL) estimates that traditional air conditioning systems account for approximately 5 percent of a vehicle's fuel usage each year in the U.S. and 3 percent in Europe and Japan. With a long history of developing thermal technology, Delphi continues to develop energy-efficient air conditioning systems that can cut those numbers in half. But for today's drivers, just properly using the air conditioning controls will help reduce fuel consumption.

Here are some tips to using a vehicle's air conditioning system more efficiently:

* Press the recirculation button to enable the recirculation of the passenger air back through the air conditioner. This button may be labeled as "MAX." Use of the recirculation feature will significantly reduce the energy used by the air conditioning system.

* For a manual system, it is most efficient to keep the temperature control in the full cold position and use the blower fan setting to adjust the amount of cooling. The temperature control should be used to adjust the air only after the blower is at the lowest setting.

* If the A/C is not as cold as it used to be, an air conditioning specialist can evaluate and repair the system. If there is a leak in the system, it should be repaired and recharged with refrigerant. It is also normal for the A/C system to lose small amounts of refrigerant by permeation through hoses over years of use. This may require a recharge of refrigerant.

* A vehicle's HVAC system may have an air filter that has caught debris and is reducing airflow. If this is the case, the filter needs to be changed. On newer vehicles, this air filter could be located behind the glove box or below the windshield wipers. It can be changed by the vehicle's owner or by service personnel. A service interval should be in the vehicle's owner's manual.

Besides optimizing a vehicle's air conditioning system, drivers can also park in a shady spot, use a reflective sun shade or leave the window partially open during sunny days.

"These simple steps allow the [vehicle] air and seats to be cooler which helps the air conditioning provide cooling comfort faster and save fuel at the same time," said James Bertrand, president Delphi Thermal Systems, Delphi Corp.

With a long history of producing automotive thermal systems, Delphi has developed energy-efficient technologies that are smaller, lighter and help reduce the impact on the environment.

From an August 2009 White Paper by Delphi Corp.