Auxiliary device intended for adding to an air conditioning device

An auxiliary device in an air conduit,

• said air conduit extending between a first air feed and a first air discharge, forming part of an air conditioning device and wherein a whole main airflow flows through said auxiliary device,
• said auxiliary device having a modular structure comprising a housing, said housing comprising an arrangement of a plurality of air conditioning modules, each of the plurality of air conditioning modules being directly adjacent another one of the plurality of air conditioning modules, said air conditioning modules are substantially identical and, in an active state, each air conditioning module allows passage of a partial flow of the whole main airflow, wherein the whole main airflow rate is a sum of the partial airflow rates passing through the active modules, and together the plurality of air conditioning modules allow passage of the whole main airflow through the first air discharge at a common outlet;
• said auxiliary device further comprising a feed part and a discharge part connected to air conduit first flow components, said first flow components produce a variable main airflow through the air conduit;
• and
• at least one control unit configured to individually transition each of the air conditioning modules between an active state, wherein passage of the partial flow is allowed, and a passive state, wherein the partial flow substantially amounts to zero or flows in an opposite direction of a whole main airflow direction;
• wherein each of said air conditioning modules comprises at least one valve, wherein each of said at least one valve is controlled by the at least one control unit, and each of said at least one valve operates between an open and a closed position, wherein the at least one valve provides a predetermined partial airflow rate for the active air conditioning module, and all valves provide a same predetermined partial airflow rate in all active air conditioning modules to meet a desired air conditioning system main airflow rate;
• and
• wherein the desired air conditioning system main airflow rate varies over time and wherein the control unit is configured to vary the number of active air conditioning modules during operation of the air conditioning system, thereby adjusting the sum of all partial airflow rates of the air conditioning modules to the desired air conditioning system main airflow rate every time said air conditioning system main airflow rate changes.