ACtion Magazine - NAPA - Spring 2016 - (Page 28)

Compressor variables that keep customers cool and save fuel By Dave Hobbs, MACS Field Correspondent ernment mandated CAFE (Corporate Average Fuel Economy) standards total around two dozen. Changing the way A/C compressors operate is one of them. See Figure 1. A/C Compressors & MPG Using A/C can contribute to more than a 25% fuel economy reduction. In one real world study published in an SAE white paper, a 2009 Ford Explorer and a 2009 Toyota Camry were tested at various speeds, both with and without the A/C turned on as well as with and without the windows rolled down. At cruising speeds of between 40 and 70 MPH, both vehicles consumed more energy with the A/C on (windows up of course) compared to driving at the same speeds with the windows down and A/C off. Ford's variable displacement compressor was running at 100% duty cycle. Both vehicles were tested again at highway speeds of around 80 MPH. The Explorer maintained better fuel economy with the A/C off and the windows rolled down compared to having the A/C on and windows up. The Camry, however, did not see a penalty in fuel US Department of Energy Summer can be hot and vacations can be pricey. A combination like that typically leads to concerns for the best comfort possible from a vehicle's HVAC system, along with fuel economy to help maximize your customers' travel budgets. This MACS Service Report will help you understand the designs and service diagnostics of the latest A/C compressors. We'll focus on belt driven conventional compressor changes related to fuel economy in order for you to help your customers go further and stay cooler, wherever their summer travels take them. Who would have dreamed 10 years ago that a new Ford F-150 truck would have extensive aluminum body construction? Vehicle weight reduction technologies such as carbon fiber, once considered too expensive for production vehicles, are making their way into the family car too. Carbon Fiber Reinforced Plastics (CFRPs) are predicted to gain widespread adoption for automotive lightweighting by 2025, one industry study group has concluded recently. In the world of fuel economy, light is right for the entire vehicle and this includes the HVAC system. The number of methods currently in use by OEM engineers to meet increasing gov- Figure 1: Of the energy within a gallon of gasoline, only around 20% actually gets to the wheels to propel the vehicle under city driving conditions. While that number goes up closer to 30% for highway driving, it's not a good statistic. Heat losses within the engine are the biggest wasters of this energy and the toughest challenge. Those parasitic losses such as turning water pumps, alternators and A/C compressors aren't huge, but do add up. 28 ACTION/NAPA * Spring 2016

Table of Contents for the Digital Edition of ACtion Magazine - NAPA - Spring 2016

ACtion Magazine - NAPA - Spring 2016
Watching yf
A/C Diagnostics and Troubleshooting
Staying visible in times of change
The compressor is not just a component
Restricted air flow
Externally Controlled variable displacement
A new Jeep
Increasing Facebook interactions
Mission possible
R-1234yf and other trends

ACtion Magazine - NAPA - Spring 2016