Inherent Heat  Vs  Heat Exchanger

The purpose of heat exchangers and electric heaters, whatever their design, is to change the temperature of liquids or gases. However, there are some differences between them. Probably the two most notable differences are: Electric heaters, as the name suggests, are used solely for heating. It is possible to design heat exchangers both for heating and cooling.

Heating processes requiring high final temperatures place heat exchangers at a disadvantage compared to electric heaters. Regardless of their efficiency, heat exchangers can heat the process liquids to just below the maximum temperature of the service fluid. Hot water (under pressure up to 150°C), steam (up to 375°C at 221 bar), and mineral or synthetic heat transfer oils (up to 400°C) can be used as operating fluids. Thus, the final temperatures of the process liquids are always slightly lower than those of the operating fluids.

Process temperatures

Heat exchangers have an efficiency ranging from 70% to 90%, depending on their design. It is also important to remember that heat exchangers require a primary heat source, the one that delivers the hot fluid. Steam boilers and thermal oil heaters, both of which are fueled by fossil fuels, supply this operating fluid. The efficiency of the heating process depends on the heat exchanger and the heat source, so listing every possible combination and the associated efficiency would be too much at this point. The actual efficiencies of the heating process are well known.


Electric heaters are almost universally used As long as the temperature remains within the range of the temperatures already described, electric heaters can be used in almost every application where heating of stationary or flowing fluids is needed. Electric heaters can be an excellent solution for heating liquids such as water, oils of all kinds, acids or alkalis, as well as gaseous media such as air, natural gas, methane, or nitrogen, to name just a few. It is nearly impossible to list all the applications for electric heaters.

The use of electric heating as a primary source of heat produces no combustion gases through open flames. Electric heaters can be installed directly into a process line without the need for additional steam or hot oil piping. For the normal operation of an electric heater, no specialised staff is needed, and they require almost no maintenance. The system is controlled by contactors or thyristors, which can vary the temperature very rapidly and accurately.