Heat recovery from exhaust air improves the energy efficiency and environmental friendliness of buildings

As the price of heating energy fluctuates, it has become timely to consider ways to curb costs and reduce emissions. A good option for saving energy is to recover thermal energy from exhaust air and use it, for example, to preheat domestic water or supply air.

As ground source heat pump systems grow in popularity, interest in heat recovery from exhaust air has also increased. When combined with a ground source heat pump system, heat recovery from exhaust air can achieve up to 70% savings in heating costs, according to various sources. Outside the heating season, the thermal energy from exhaust air that is not used for heating domestic water can be recharged back into the energy well to be utilized during the next heating season. This extends the lifespan of the energy well and allows the efficient use of resources, benefiting both the environment and the wallet.

ETS NORD has introduced a new series of exhaust air units designed for heat recovery, intended for outdoor installations. These Recair E-series units are suitable for both new buildings and renovation projects where old exhaust fans are to be replaced with recovery units and used alongside existing heating systems. In new buildings, the unit can be used as an exhaust unit in places where there is no space for large air handling units or where separate local exhausts are needed. The unit can be installed separately from the supply air unit, with the recovered thermal energy being transferred to the supply air unit using a heat transfer fluid.

The design of the Recair E-series units allows installation directly over a roof transition. Alternatively, the exhaust air duct can be connected to the end of the unit, making it also easy to connect multiple small local exhausts if needed.

The E-series heat recovery unit can also be used as an exhaust air unit for professional kitchens, provided that the kitchen canopies are equipped with appropriate grease filters and cleaning systems. The exhaust air from professional kitchen canopies contains a significant amount of thermal energy, so by connecting a heat recovery exhaust unit to the heating network of the supply air unit serving the kitchen, substantial energy savings can be achieved.