Thread: Room Dust Filters - need a diffuser?

without getting into particle sizing, a three stage filter would successfully filter out coarse, medium and fine particles.

Leaving one of the filter stages out will likely lead to over rapid clogging of the next finest filter.

Originally Posted by ian

without getting into particle sizing, a three stage filter would successfully filter out coarse, medium and fine particles.

Leaving one of the filter stages out will likely lead to over rapid clogging of the next finest filter.

I think he's referring to the media on the output? which is indeed intended as a diffuser although it probably doesn't do that much.

Yes, the first outer filter is a removable paper like cartridge rated at G4. Next comes a lung like configuration, rated at F6. There is an option of a further filter (the manual calls a carbon filter). These are in front of the fan (squirrel cage).

Behind this, on the rear (exit side) is a steel wool like thing. It feels very nasty. Like an old grease trap you might have above a range hood. It doesnt seem to serve a purpose. Pic attached.

TIA.

BTW, The people from FilterTech are very obliging. They will even make me up a filter that is super-dooper, but this comes at a price.

BBTW, it strikes me as how primitive the understanding of filtration is here in Oz. Finding a decent company is almost impossible (there appears to be 4) but prices are 10x higher too. All these items are throw-away bulk order items for home aircon and heating in the USA, direct from Amazon. Here is all Special Order.

DSC02780 (1024x774).jpg

Originally Posted by woodPixel

Yes, the first outer filter is a removable paper like cartridge rated at G4. Next comes a lung like configuration, rated at F6. There is an option of a further filter (the manual calls a carbon filter). These are in front of the fan (squirrel cage).

Behind this, on the rear (exit side) is a steel wool like thing. It feels very nasty. Like an old grease trap you might have above a range hood. It doesnt seem to serve a purpose.

the final (exit) filter will have some purpose beyond cosmetics, we just for the moment don't know what it is.

the "carbon filter" is presumably to trap vapors like paint and finish fumes.

Originally Posted by ian

the final (exit) filter will have some purpose beyond cosmetics, we just for the moment don't know what it is.

after a bit of googling and reading, diffusers come in a variety of flow patterns which seem to have the purpose of either directing the air flow down stream of the fan unit, or to spread the fan driven flow out so that you don't get a "jet stream" effect where air circulates near the ceiling rather than through the whole room.
I found a 64 page sales brochure on what diffuser you might use where. In a workshop or shed it looks as though the diffuser should be designed to ensure all the air in the shed circulates through the filter unit.

(Of course, proper design for air movement and a tool sold to the budget conscious home user are likely to be is a contradiction.)