Idling costs you money. Engine off. Climate on.


Webasto presents: automated Engine-Off Heating & Cooling Technology. An ingenious way to maintain comfort and the efficiency of your machines throughout the whole day  – and still cut costs effectively!


To keep the engine at normal operating temperature and maintain comfortable temperatures in the driver's cab, it’s common practice to leave the engine running when vehicles are stationary or waiting. Engine idling often accounts for up to 50% of total engine time!

As the chart clearly shows, in terms of the share of total operating cost over the entire life span of a machine (“total cost of ownership” or TCO), idling can increase expenses by up to 17%.

Although the machine is not being put to productive use, fuel continues to be unnecessarily consumed and the number of operating hours still goes up when the engine idles. The former has an effect as a direct cost-driver, while the latter has a huge impact on the vehicle’s resale value, frequency of maintenance and warranty requirements.


Engine-Off technology


Your advantages

  • Heating and cooling from a single source
  • A constant 69.8°F (21°C) - 365 days a year
  • A ready-for-duty driver at all times
  • Up to 90% less fuel consumption
  • Diesel particulate filters stay clean longer
  • Made-to-measure climate systems
  • Up to 60% fewer operation hours
  • Less wear-and-tear, less maintenance
  • Save up to $7,793.00  (€7,000) per vehicle and year

How Engine-Off Heating (EOH) technology works


1. Engine running:
The engine generates heat, which is circulated via the cabin heat exchanger.



2. Without Engine-Off Heating Technology – engine is off:
When the engine is switched off, heat is no longer distributed to the cabin interior through circulating coolant. The thermal energy stored in the engine is lost; the cabin interior and engine cool down.


3. With Engine-Off heating technology – quick stop:
Residual heat in the engine is still used by the heater, as the Webasto circulation pumps keep residual heat moving through the cooling system. The temperature in the cabin interior remains stable.


4. With Engine-Off heating technology – longer stop:
If the engine continues to cool down, the residual heater also switches on automatically. The engine and cabin temperature remain stable.



The automatic Engine-Off heating system activates the coolant heater the moment the engine stops. As a result, the temperature stays within the optimum range, for machine operators and machinery. This makes restarting the engine more efficient and easier – even after a prolonged break between operating. In comparison to idling, this uses much less fuel. So it’s actually possible to save over 90% on fuel!


How Engine-Off Cooling (EOC) technology works


1. Engine running
The vehicle engine is running, the vehicle own HVAC system delivers cool air. Vehicle own compressor is running.





2. Engine off - external compressor on

The vehicle engine is switched off with start/stop functionality. The external compressor replaces the vehicle own compressor while the engine stops running.




The vehicle compressor switches off as soon as the engine stops running. An exterior compressor, however, receives energy via the vehicle battery and is operated via an external motor. It starts up when the vehicle engine is turned off.



Further information

Engine-Off brochure

Download here our new Engine-Off brochure

Download (PDF, 552 kB)

Our contact

Webasto Thermo & Comfort
North America, Inc.
15083 North Road
Fenton, MI  48430