Relation of Rated air flow of Hepa filter and Blower Airflow

[MACL]

Hello,

What happen if your blower airflow is greater than the Rated Air flow of HEPA filter, does it decrease the efficiency of the HEPA filter?

Please respect post.

 

[SAK9]

Please plot the system curve(ductwork,HEPA etc) against the blower performance curve.HEPA filter will give a higher airflow indicated by the intersection of the two curves

 

[MACL]

Thank you for your respond SAK9. So it is recommended to have a lesser blower airflow compare to the rated airflow indicated in HEPA filter? Sorry I am a newbie

 

[SAK9]

The fan will be on a VFD so its speed will vary to maintain design airflow rate.Also bear in mind that HEPA filter constitutes a big chunk in system resistance and it goes up(doubles) as the filter gets dirty.

 

[MACL]

Thanks SAK9. I have HEPA Filter with a rated airflow of 1000 cfm and 1 in. W.G resistance. So it will be okay if my blower have an airflow of 1000 cfm then 1.5 in. W.G right?

 

[MintJulep]

The fan needs to provide the needed flow considering the pressure drop of the entire system.

A filter is likely only one part of the system.

As SAK9 implies, a HEPA filter's performance changes with time as it does it's job. Your fan needs to consider this change as well.

 

[LittleInch]

You would need to ask the vendor I think but its usually not good to exceed vendors recommended limits.

But it's DP which is usually the key issue.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.