Cummins introduces ComfortGuard APU System

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The new ComfortGuard APU from Cummins is the engine manufacturer’s first complete auxiliary power unit system for over-the-road trucks. The system combines the company’s Onan generator with tailored HVAC components to power all hotel loads for comfort and convenience. The quiet, compact and reliable system offers an effective solution to anti-idling regulations and the high cost of diesel fuel, Cummins says.

“With an increase in legislation and enforcement of truck engine idling laws and the rising cost of fuel, APUs are a must for over-the-road truckers,” says Shawn Wasson, APU business leader for Minneapolis-based Cummins. “A Cummins ComfortGuard APU system can pay for itself through reduced engine idling in about 18 months or less. The ComfortGuard APU system is a logical outgrowth of both the engine and idle management products for which Cummins is known, and the RV, marine and mobile generators built under the long-established Onan brand from Cummins.”

The company says the ComfortGuard system’s plug-and-play design reduces the cost of installation by up to one-half; quick disconnects, pre-charged A/C lines and compact dimensions allow system installation on most trucks in about a day. The ComfortGuard system is designed to reduce wear and tear on truck engines, and to match the engine’s oil change interval of 500 hours.

The Cummins ComfortGuard system’s Cab Air heating and cooling components are compact and offer high performance, according to the company; the space-saving A/C system fits beneath the sleeper berth and has a 12,000 Btu capacity to maintain comfortable temperatures inside the cab. The 4,000/8,000 Btu, two-stage electric heating element provides comfort in the coldest weather, while the evaporator section, which also mounts under the bunk, delivers up to 350 cubic feet per minute of cool, comfortable air, Cummins says. Both heating and cooling are controlled by a thermostat similar to the ones found in most homes; the ComfortGuard Cab Air APU system can be programmed to start automatically based on thermostat settings or time of day.

The ComfortGuard Cab Air condenser section is contained in a heavy metal case that protects coils from road grime, rocks or gravel that can be thrown up by the tires and cause major damage. Unlike similar units that have to be mounted vertically, the ComfortGuard Cab Air condenser is designed to mount in any orientation – upside-down, right-side-up or lying flat on its back.

The ComfortGuard APU system is powered by a two-cylinder diesel engine – the same engine as used in many Onan RV generators that are designed for low noise and low vibration. Equipped with a Cummins alternator, the unit produces 4,000 watts at 120 volts, 60 Hz AC, with exceptional voltage and frequency stability for sensitive appliances and electronic equipment, the company says; it also produces up to 40 amps at 12 volts DC for charging the truck’s batteries, and powering lights and fans. Weighing 375 pounds, the ComfortGuard APU system is within the allowable gross vehicle weight variance for tractor-trailers equipped with APU equipment.

The unit comes standard with ground fault interrupter (GFI) outlets for added safety and to allow easy reset from inside the cab. The APU also features self-diagnostics with a built-in microprocessor and LCD readout; at the touch of a button, the operator can program automatic controls or check coolant temperature and overall operational history. The durable, powder-coated steel enclosure opens easily, providing quick access for service, according to Cummins. Overall dimensions are 21 inches long, 24.5 inches deep and 28 inches high, making it compact enough to mount behind fairings.

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