Thread: Shop vac washable filters worth it?

Originally Posted by John G

That's what confused me. Why in your second diagram RHS ("Best solution for inside shed") is the VC in a box? If venting directly outside, why the box?
e.g.

There are two reasons for the box
1) The VC is inside a box to redirect the motor cooling loop air outside the shed, otherwise the motor cooling loop fills the shed up with (least healthy) very fine dust.

The motor cooling loop on VCs act like very fine dust generators.
If a high air flow DC is not used, sheds end up full of fine dust which VCs are either incapable of capturing at source or subsequently removing because their air flow is too low.
The fine dust floating around in the shed goes through the motor cooling loop and is minced into finer dust which increases the concentration of even finer dust particles inside the shed.

2) Leaks
Every VC more than a couple of months old that I tested demonstrates some level of dust leakage usually because seals are dirty or damaged, and/or cracked or damaged canister closures. Old VCs that are towed around sheds on the ends of their hose generally exhibit more leaks than those that are kept in one place.

Putting a box around the VC and forcing the air inside the box outside the shed gets rid of these sources dust.