The multi-service active chilled beam, DID600B-L, is used in low height construction, is flush-mounted in ceiling or is integrated with linear light fittings. The spigots located at the top or side provides exchange and entry of fresh air with a horizontal project compact dimension. The upper plenum box connecting through a spigot enables entry of primary air volume flow to supply fresh air. The diaphragm fitted with a nozzle discharges fresh air into the mixing zone. The induced air is drawn from room rather than the ceiling void for hygienic reasons. During the passage of air through water coil, it is cooled down (chilled water operation) or warmed up (warm water operation) as per need. The air is then mixed with primary air in mixing section and discharged via slots into the rooms for heating/cooling. The device can be fitted with an additional spigot for extracting the exhaust air.