On 7/25/2012 2:26 PM, Puckdropper wrote:
wrote in :

*snip*


OBTW -- on the 30-ga HVAC stuff--I've not tried it on a 2 hp collector
but it will all depend on what pressure drop your fan will pull. At
worst buy a section, hook it up to the inlet directly and do a block
test and see if you can collapse it or not.

If you're worried about collapsing, a simple pressure relief damper can be
installed at the end of the run. All it is is basically a damper that can
turn freely that is weighted at one end. In normal operation, the damper
stays closed for maximum draw from the outlets. In a clogged/choked
condition, the damper opens to take the pressure off the pipe.
....

Oh, gee, and take all the suspense out???

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