The three main functions of heating, ventilation, and air-conditioning are interrelated, especially with the need to provide thermal comfort and acceptable indoor air quality within reasonable installation, operation, and maintenance costs.
HVAC systems can provide ventilation, reduce air infiltration, and maintain pressure relationships between spaces. This is achieved with the use of air distribution networks using rigid and flexible ducts.
- Process rooms
- Packing / Filling rooms
- Maturing & Ripening rooms
- Cold Stores
Together with the Air Contamination Control, air distribution is fundamental in the food-processing industry. This is due to the fact that the air should be sanitised, with correct number of re-circulations all over the volume of the rooms, to avoid stagnant zones.
Air conditioning methods differ according to the humidity level required by the conditioned rooms and by the presence or not of workers in the mentioned rooms. Production, processing and packing rooms generally need a smooth air flow dropping from the ceiling and exhausted just above the floor, to obtain a sort of laminar flow that “clean” the room. Typical air distribution in a packing room, where the air flows from textile ducts from the ceiling and it is exhausted from grill just above floor level at the four corners of the room.
Some products like cheeses needs a quite long period of ripening and the weight loss problem is a sensible one since few % points of weight loss means a very big amount of profit or loss.
In maturing and ripening rooms, proper air flow is required also for a correct ripening of the product.
Uniform distribution create a uniform quality of the product, and also the weight loss is minimised, due to a better control of the humidity all over the storage and ripening volumes. Each product and each step of the ripening process needs a specific air distribution system correctly sized to avoid to affect the desired humidity content of the product and of the surface of the product. Temperature control is quite simple, but this affect the humidity content if the temperature of the refrigerant and consequently the coil surface one is not properly design. Undersized coils in general reduce the humidity in such a way that the weight losses increase dramatically.
Long seasoning ripening rooms generally require a deep diffusion system to have all the products at the same condition, but at the same time to avoid hard air impact against the product that could affect the quality and create problems on the surface.