APU (Auxiliary Power Unit)

HOTSTART's diesel-powered locomotive heating system eliminates idling when a locomotive is shut down or put in layover where no electrical service is available. Operating independently of other locomotive systems, the HOTSTART APU circulates heated coolant through the engine, compressor, expansion tank and oil cooler to keep the entire locomotive's water system warm during shutdowns. Depending on ambient temperature, the system will maintain the prime mover's coolant between 90-120°F while also maintaining the battery's full charge. The HOTSTART APU is small enough to fit in the nose of most locomotives as well as any car body or walkway.

Heat loss through wet cooling systems (wet radiator) during heating system operation may reduce or impair the heating system’s ability to maintain optimal heat levels for engine operation or engine start.

The compact HOTSTART APU allows for multiple installation possibilities.

Inside mount on GP-35 at Montana Rail Link

Inside mount on SD45 at Eastern Gateway Railroad

Inside mount on GP38-3 at Rail Trusts Equipment Inc.

Walkway mount on GP-8 at Maumee & Western

Nose mount on GP-9 at Butte, Anaconda & Pacific Railway

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