In boiler-houses, working on liquid fuel (both main and backup), heating of this fuel (fuel oil M100, M40) uses more than 15% of heat of its combustion. For fuel oil brands M200 and “Component” this value even more. The situation is aggravated by the fact that the majority of boiler-houses with water-heating boilers do not have the steam necessary for the conventional heating scheme of fuel oil. The purpose of installing small steam boilers requires high costs and is inappropriate.

The Institute developed a heating system for heating oil followed by flue gases using a part of a full-time boiler economizer. The calculations of the actual heat transfer surface of the boiler economizer are actually carried out taking into account the actual maximum load of the boiler. Given that boilers are usually not new, the actual allowable load is usually 15-20% lower than the estimated one. Thus, it is possible (ascertained by calculations) the use of 15-20% of the surface of the regular economizer for heating fuel oil in them. Such a reconstruction of the boiler does not require high costs of funds, but involves installing a drainage system to clean pipe bundles from fuel oil when the system stops and before it is loaded.
The use of such a heating system allows to save at least 15% of fuel oil by reducing the cost of own needs.

The payback period of the necessary re-equipment is not more than one year.