Filter for Central Unit A/C

Thanks for this question. This is a serious issue for all industry where centralize cooling used via Air Handling units (AHU). Another concern is the moisture involved in side the food production plants since steam, hot and cold temperature and some water sprayers are involved. There should be some filters to control or filter out not only the dust and airborne pathogens but also the moisture and foul processing air. I am currently not have a solution but looking for the same solution.

May be many of our forum experts have good ideas. Expect CR4 volunteers to focus on this!

Hari

use dust collecter along with moisture separator,available in market

you can use unitechs centrigugal separation filters [microfiltration] in ur systems to remove pollen and micro-organism,its having no moving parts,no filter elements to clean or replace,on line system is available

Good answer. Please could be possible to get more details and pictures? please give approprite links, more help

Thanks

write down detail problem u r facing at unitechint@sify.com

I will have to prepare some sketch, I will be back shortly

Thanks unitechint

You can use HEPA filters for this purpose. They are used in cleanrooms so they'll definitely meet your needs.

If you are looking for roll filters you can only use them as a pre filter, so only the incoming air is removed from the bigger dust particles. You will have to place at the end of the airhandling unit (AHU) an end filter that removes the smaller particles. By choosing for certain classes ( Merv 11 - 15) you can decide how small the particles will be that you will catch and also the efficiency of the filtering.

You must take in account that the higher the quality of the filter, the higher the pressure drop over the filters will be. You will need to look at the capacity of your fan!

If you also want to eliminate microbial contamination you can use a HEPA filter (Merv 16 and up). In this case you will also have the disadvantage of the increasing pressuredrop. You must also consider that the way you build in the filters (without leaking air via by-pass) is determining the efficiency of the system. These filters are also quite expensive and must be changed regularly.

Another possibility is to choose for a "normal" end filter (Merv 11 - 14) to catch the dust particles and add UVC lamps into your duct work to kill the microbial contaminants; theu will also eliminate viruses and bacteria. The lamps cause no pressure drop. You must take some precautions concerning safety, because people must not be exposed to the light.

Dear Rien

Good suggestion.

I would look more into two options. One as you suggest a reasonable sized filter and UV radiation. Second following the earlier thread "unitechs centrigugal separation filters [microfiltration] in ur systems to remove pollen and micro-organism,its having no moving parts,no filter elements to clean or replace,on line system is available".

If the second mentioned is effective I think adding UV will make it more effective.

Please update if there are better options

Hari

Usually there are three type of Filters are used in AHUs depending upon the clean room class level to be maintained. They are prefilters,Bag filters,Electronic filters and finally HEPA filters. HEPA filters are used in conjunction with Laminar flow and mostly used in Operation theater and clean room areas.

Hi Guest,

You are asking for specific information in what is a very sophisticated part of the HVAC industry without giving us sufficient information to provide the guidance that is needed to start the selection process.

I suggest that you start by contacting one of the established product manufacturers to gain some positive direction eg. vokesair.com ;having used their products for many years they can be relied upon, both for advice and product quality.

Regards,

Massey