Case Study: Displacement Air Conditioning For High Care Production Area Penmann were asked by a leading Dairy Product manufacturer to design an air conditioning system for a 10ºC high care dairy product filling area. The client required 100% fresh air system filtered to H10 standard to minimize any risk of contamination with yeasts and moulds.

The client also needed to run CIP on certain lines whilst maintaining production on others. The full fresh air option prevented the possibility of saturating the final filters with moisture generated by the CIP process.

The difficulty with full fresh air systems, and particularly for lower temperature areas, is that a significant cooling load is imposed by cooling the external air regardless of the internal gains within the area. To minimize the volume of air a displacement air distribution system was used which effectively reduced the required air volume to 65% of that of a conventional mixing system. Further to this free cooling was obtained by passing the incoming fresh air over an enthalpy wheel to recover any sensible and latent cooling effect from the system exhaust air. The refrigerant plant size was halved by the use of the enthalpy wheel.

The displacement air distribution arrangement also provides an excellent dilution rate of room air which speeds the removal of any steam generated by CIP processes. To ensure maximum life from the 3 stage filtration system and ensure the room remains positively pressurized the fan speed was controlled with a frequency inverter to maintain a constant air volume as the filters become dirty.

Key Features

• Energy efficient displacement air distribution
• Full fresh air option to prevent fogging and enhance filter life
• Use of free cooling for energy efficiency
• Frequency inverter to maintain constant air volume to obtain full filter life