UVC-filter breakdown question

[Guest guest]

Many UV manufactures specify a minimum distance to be installed from HVAC filters. Some of those same manufactures also market 4" media filters but neglect to mention anything about minimum distances from UV lamps. Shortsightedness on their part because I have seen installers, that knew nothing about effects of the existing UV lamp, install a media filter that was eaten alive within 60 days.

Does anyone know whether a cotton, fiberglass, poly blend etc filter is more resistant to UVC? I see some media filters that have incorporated a UVC lamp inside the casing and another inside a one inch filter so UVC must not deteriate all filter materials.

Thanks,

Greg Hatfield, CIE

iaqman2@...

From: iequality [mailto:iequality ] On Behalf Of Redington, CurtisSent: Monday, April 10, 2006 4:48 PMTo: iequality Subject: RE: Re: efficacy of germicidal UV

The situation I observed involved deep pleat filters (e.g., "Space Guard" or "Air Bear") that are typically replaced annually. The U.V. light deteriorated the filters very quickly. Huge holes in the filter(s) within only a week or two. HVAC company's customer was very particular - that's why the money was spent on U.V. lights, by-pass HEPA unit, etc. As you can imagine, the customer was not happy about filter fibers blown all over the house. Although the HVAC company is usually very good, someone goofed up and installed the U.V. lights within line-of-sight of the filters (on both of the two systems in the home). The same reasons that U.V. may have useful applications for reducing microbial growth, slime formation, etc also means you've got to use it appropriately or you can make things worse (but isn't that true for a lot of thing?). In this case, the clean up costs alone exceeded $1,500.

Curtis