Air conditioner

An air conditioner 100 comprises a heat exchanger 14 used to either cool or heat a room 'H' with the heat exchanger 14 located between end plates 13a1, 13a2 and being located in a housing 10 formed of a one piece plate blank having a perforation 10a for the passage of airflow L2 circulated from the room 'H'. Housing 10 may comprise of a bottom plate (11a1 fig 2), side plates (11a2) and a top plate (11a3) having bent locking edges (11a4) that engage with a locking notch (17, fig 4) of a locking part (16), which is attached to the end plates 13a1, 13a2. The circulated airflow L2 from the room 'H' may be brought into the air conditioner 100 from the side. The air conditioner 100 may also comprise of a fresh air supply chamber 12 communicating fresh air L1 from outside the room 'H' via a duct 'P' into a mixing chamber 'B' via nozzles 12a1 or a nozzle gap and thereby inducing the circulated airflow L2 from the room 'H', which may be heated or cooled by the heat exchanger 14. Mixing chamber 'B' thus creates a combined airflow L1 + L2 that is heated or cooled for communicating to the room 'H'. The one piece plate blank forming the housing 10 may be bent into an acute angle a less than 90 degrees (fig 6) so that a spring force causes locking edges (11a4) to lock with the locking notch (17) in tension.