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Three Maples
01-22-2017, 04:54 AM
Last year I installed a high pressure fan on my arch. I thought if I put the fan on the outside of the wall it would be ok for noise. I was wrong the high pitch whine of the fan made for a long season. We tried putting up noise barriers against the wall finally I had to wear ear plugs which helped but was not much fun. During the summer I built a fan house and moved the fan about 20 feet from the sugar house. I thought there that should do it again I was wrong; the sound followed the pipe into the arch and was as bad as with the fan mounted on the outside wall. I was told that I should make a pipe that is in a circle as that would cancel the sound waves, wrong again. I decided to make a muffler and finally something that works. With the muffler installed all you hear is the rush of air into the fire box.
I used a thirty gallon plastic barrel, 1 1/2 foam egg crate, 3” foam board insulation and 4” drain pipe. I cut the top off the barrel about 3” down, drilled a 4” hole in each end, and lined the end and sides with the foam egg crate. The egg crate on the sides are cut at an angle to accommodate the foam insulation board witch is cut oblong to be at an angle in the muffler. I drilled the foam board with ¾” holes to act as a sound chamber. The pipe goes thru the foam board to help hold everything is place and forces the air to circulate thru the board to get to the outlet. When all egg crate sides are in place the end goes back on the barrel. Because the barrel is tapered it can be overlapped and attached with self-tapping screws. All joints and connections are sealed with aluminum duct tape, not regular duct tape aluminum, its expensive but works much better. I connected the muffler with 4” dust collection hose from the dust collection system in the wood shop in the 4” soil pipe buried from the fan house to the sugar house. Finally all’s quiet on the sugar house front.
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RileySugarbush
01-22-2017, 11:06 AM
Nicely done! You can think of a high pressure radial vane blower as a poor siren. They do make a lot of noise (look up how sirens are designed!) Did your pressure at the arch drop much?

Three Maples
01-22-2017, 01:23 PM
I did not see a noticeable drop in air volume, that is the beauty of high pressure it can overcome restriction without the loss seen in high volume low pressure fans.