The flue gas heat exchanger is designed to save energy by lowering the flue gas temperature, which it does by heating the network return water.
Flows of flue gas contain a large amount of thermal energy. With their highly-efficient heat recovery surfaces, economizer modules are able to utilise this potential, thereby significantly increasing the efficiency of new and existing steam boiler systems. The flue gas heat exchanger downstream of the boiler is used for 'dry' operation in order to heat up the feed water. To permit the use of condensing technology, an additional downstream flue gas heat exchanger module can be fitted to facilitate flue gas condensation and heat make-up water. These modules can be retrofitted to existing single-flame steam boiler systems extremely easy.