Heat recovery is the main purpose of this type of devices. Typically, energy is utilized from flue gases formed in furnaces after the combustion of natural gas or other fuels. These gases are usually simply emitted into the atmosphere in a large volume, although in this event their temperature can reach 500-600 °C. However, if you install a gas heat utilizer in the line, all this heat may be directed to your own process needs. Often, exhaust gas heat utilizer is used as a water heater. It is also possible to use to heat the premises or to preheat air before it enters the boiler. Such an arrangement will make it possible to save natural gas or other fuel, increase the boiler service life, and improve its efficiency. The most common type of heat exchangers used as a flue gas utilizer will be tube heat exchangers and plate heat exchangers (but with flat plates). For such purposes, it is very important to observe extremely low pressure losses. This is important for the optimal operation of the entire system of gas supply and its further use. Therefore, before installing a gas heat utilizer into the line, it is necessary to calculate first its effect on the installed equipment.