Dynamic / Electrostatic air filters

[Guest guest]

Hi All:

Just wondering if anyone is familiar with effectiveness of

electrostatic filter banks. We have our return air being filtered by a

bank of about 200 filter pads in electrostatic housings. Six of our 15

large Haakan rooftops have been fitted with these filter housings and

electrostatic filters. The media is a composite of fiberglass type

matting sandwiching a carbon filter media. The return air is being met

by the filter bank and then goes through a heat wheel. After that, it

goes to the mixing chamber where it either mixes with outside air or

goes into the outside air via the economizer dampers. However, mostly

the outside air dampers are open to exhaust 100%. Very little return

air is mixed with supply air.

Thanks for the replies in advance.

LEW

[Guest guest]

Dear Lew,

It has been reported that the electrostatic

filters do not operate very effectively under high RH conditions…typically

higher than 60% RH.

Maybe there is some way to check for the

efficiency levels while in operation…What Minimum Efficiency Reporting

Value (MERV) Number are

these filters currently specified for?

Best regards,

W. , CAFS, NCT II

AIR INDUSTRIES, INC.

North Andover, MA 01845

NAFA, Past President 2006-2007

Office:

Fax:

Mobile:

Dynamic /

Electrostatic air filters

Hi All:

Just wondering if anyone is familiar with effectiveness of

electrostatic filter banks. We have our return air being filtered by a

bank of about 200 filter pads in electrostatic housings. Six of our 15

large Haakan rooftops have been fitted with these filter housings and

electrostatic filters. The media is a composite of fiberglass type

matting sandwiching a carbon filter media. The return air is being met

by the filter bank and then goes through a heat wheel. After that, it

goes to the mixing chamber where it either mixes with outside air or

goes into the outside air via the economizer dampers. However, mostly

the outside air dampers are open to exhaust 100%. Very little return

air is mixed with supply air.

Thanks for the replies in advance.

LEW

[Guest guest]

Mr. : I don't have the MERV rating on these filter pads but I would say they are comparable to a MERV 7 or MERV 8 rating. I'm trying to get a "comfort level" on the usefullness and net worth of these installations. They are a bit of a preventive maintenance difficulty as there are many filter pads that make up one filter bank. Filter changes at every 3 months or so are not met with wild anticipation. And, as far as IAQ effectiveness I wonder if anyone has found the tradeoff to be worthwhile? Are there any difinitive studies that show the improvement to IAQ after installation or is it a lot of "smoke and mirrors" that typically fill a sales persons repertoire? Regards, LEW" W. " wrote: Dear Lew, It has been reported that the electrostatic filters do not operate very effectively under high RH conditions…typically higher than 60% RH. Maybe there is some way to check for the efficiency levels while in operation…What Minimum Efficiency Reporting Value (MERV) Number are these filters currently specified for? Best regards, W. , CAFS, NCT II AIR INDUSTRIES, INC. North Andover, MA 01845 NAFA, Past President 2006-2007 Office: Fax: Mobile: -----Original Message-----From: iequality [mailto:iequality ] On Behalf Of lewenz01Sent: Wednesday, January 16, 2008 11:21 PMTo: iequality Subject: Dynamic / Electrostatic air filters Hi All:Just wondering if anyone is familiar with effectiveness of electrostatic filter banks. We have our return air being filtered by a bank of about 200 filter pads in electrostatic housings. Six of our 15 large Haakan rooftops have been fitted with these filter housings and electrostatic filters. The media is a composite of fiberglass type matting

sandwiching a carbon filter media. The return air is being met by the filter bank and then goes through a heat wheel. After that, it goes to the mixing chamber where it either mixes with outside air or goes into the outside air via the economizer dampers. However, mostly the outside air dampers are open to exhaust 100%. Very little return air is mixed with supply air.Thanks for the replies in advance.LEW