DENSO Develops Smaller Air Conditioning Unit for Compact Car; First Application on the iQ
22 October 2008
DENSO Corporation has developed a new air conditioning unit which is approximately 20% smaller in volume than the conventional product. The new system will be installed on Toyota’s new iQ compact car to be launched in Japan in November and in Europe in early 2009.
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| The new DENSO AC unit. Click to enlarge. |
With improvements including new resin molding technologies, DENSO reduced the size of the blower fan for the new air conditioning unit. This allows the blower unit containing the blower fan to be reduced by almost half the size of the conventional unit, contributing to the size reduction of the air conditioning unit.
The new air conditioning unit also can be mounted in the center of the instrument panel to create more legroom for the front passenger. DENSO achieved this by integrating the blower unit—which generally is separated from the main unit and located above the front passenger’s leg space—into the uppermost side of the main unit.
My first and foremost question is this: What refrigerant is used? We can't use chlorofluorocarbons any more (because the chlorine content bleaches away the ozone layer), we can's use fluorocarbons (because such compounds are hundreds or thousands of times more potent as greenhouse gases). So what does Denso use as a refrigerant?
Posted by: Alex Kovnat | 22 October 2008 at 04:18 AM
These things generally don't care about the refrigerant. It's just a system to put evaporating liquid on one side of a barrier and blow air over the other; it's limited by pressure and chemical compatibility and not much else. R-12 systems can be converted to R-134a, and I don't doubt that the Denso unit could run on HFCs or even a mixture of propane and isobutane with the right vapor pressure.
Posted by: Engineer-Poet | 22 October 2008 at 09:35 AM
Propane and isobutane aren't a threat to the ozone layer, nor are they (in reasonable amounts) a global warming threat. Unfortunately, mother nature pulls a trick on us in that, if a car using these materials as refrigerants is involved in an accident, you're going to have a fire/explosion hazard.
Since nothing is without problems, we have to set priorities and live with the problems of whatever we decide to use or do.
Posted by: Alex Kovnat | 22 October 2008 at 09:48 AM
Propane and isobutane are just as explosive as gasoline vapor. I doubt the propane/isobutane reservoir for a cooling system will have much more total volume than what you have in gasoline outside of the gas tank.
Posted by: | 22 October 2008 at 04:58 PM
whatever happened to using CO2 as a refridgerant?
Posted by: GreenPlease | 22 October 2008 at 06:08 PM
Denso uses R-134ａ since 1999.
http://www.globaldenso.com/en/csr/report/1999/pdf/09.pdf
Posted by: ken1784 | 23 October 2008 at 04:17 PM
Very pure propane is less of a fire hazzard than R134. All new refrigerators in Germany use pure hydrocarbon refrigerants. Carbon Dioxide requires tubing that can withstand ten times the pressure of propane and may not even work in some climates; the compressor and seals need to resist those pressures too. The belt driven compressor should be eliminated for an electric one taht can be sealed for the life of the carand mounted on the frame. LG makes very efficient free piston ones with no crankshaft. ..HG..
Posted by: Henry Gibson | 25 October 2008 at 07:05 PM
Very pure propane is less of a fire hazzard than R134. All new refrigerators in Germany use pure hydrocarbon refrigerants. Carbon Dioxide requires tubing that can withstand ten times the pressure of propane and may not even work in some climates; the compressor and seals need to resist those pressures too. The belt driven compressor should be eliminated for an electric one that can be sealed for the life of the carand mounted on the frame. LG makes very efficient free piston ones with no crankshaft. ..HG..
Posted by: Henry Gibson | 25 October 2008 at 07:13 PM