What are the advantages of using preheating resistors?

It is essential that a generator set, operating in emergency, takes the load quickly and reliably, when there is a power failure, at the main source. For this to occur, the preheating resistors are essential, because they keep the antifreeze warm and make it circulate through the engine block, ensuring that it is always at a controlled temperature and ready to start at any time.

The heating of the engine of a generator that is inside a building with controlled temperature will necessarily be different from one installed outdoors at a lower temperature. Therefore, the preheating resistors are crucial to maintain the ideal temperatures of any generator, anywhere.

For engines with larger displacement in which the heating volume is higher, pump heating resistors are recommended, because they allow the effective circulation of the antifreeze without heat dissipation.

Failure to install this equipment can lead to the group not being able to start instantly, which for buildings that have equipment that must be operational 24/7, such as hospitals, hotels and, among others, power plants, is highly damaging.

On the other hand, the use of this component has great advantages:

  • Continuous heating means that the generator is always at the ideal temperature to operate;
  • Starting is easier and faster;
  • Preserving the battery in good condition by optimizing its life span as it maintains ideal temperature conditions;
  • The engine is less subjected to wear and damage.


There are several factors to consider when choosing the generator that best suits your needs and your reality. These aspects go beyond the power you expect and the equipment you want to feed, because they are related to the specific characteristics of the installation site and the mode of operation you want.

Many potential problems, which arise from downtime and unfavorable conditions, such as extreme climates, can be easily remedied with the incorporation of some extras, that are able to guarantee the effective operation of the generator, as is the case with engine preheat resistor.

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