The new ClearSky diesel particulate filter (DPF) has been conditionally verified by the California Air Resources Board (CARB) for use with Carrier Transicold’s ComfortPro auxiliary power unit (APU). This allows operators of class 8 tractors with 2007 or newer engines to use these APUs with the new DPF throughout the state.
 
Active-regeneration technology in the new DPF achieves CARB’s emission standard, which calls for particulate emissions to be reduced by at least 85%. It also meets CARB’s NOx (nitrogen oxide) emission regulations.

Active regeneration might be considered impossible because these units typically don’t generate enough heat to burn off particulates from the exhaust. Carrier says the ComfortPro’s Deltek hybrid diesel-electric technology is unique, and its generator creates the necessary temperatures.

With a silicon carbide filter element and an easy-to-maintain design, the ClearSky DPF replaces the ComfortPro muffler on new equipment, and it can be field-installed on existing units (model PC6000). Requiring no driver intervention, the DPF automatically regenerates in less than 25 minutes, every 10 to 30 operating hours.

Without a DPF, some truckers are now prohibited from running their diesel-powered APUs in California. The California law applies to trucks equipped with a 2007 or newer engine. Rigs with older engines may still use the ComfortPro APU without the DPF in California. And, even without the DPF, operators of newer rigs can take advantage of the APU’s shorepower option when parked at any California location where an adequate 110-volt power supply is available.