Cyclone outside venting

[Dan Chouinard]

We are considering outside venting for our 5hp Oneida high vacuum cyclone. Any guidance/considerations regarding outside venting would be greatly appreciated.

[Ed Aumiller]

You will be sending a lot of conditioned air outside and will have to condition the air replacing it... Heating in winter, cooling in summer...
Raises your utility costs and also comfort levels until incoming air is conditioned...

[Michael W. Clark]

If you have any neighbors, you may not want to point the exhaust at them due to noise. If horizontal exhaust, make a 45 miter cut on end and put on bird screen. If you go vertical, you can use a no-loss stack or rain cap, but put a drain port in bottom of elbow to remove water just in case.

[Andrew Seemann]

Also, if you are using combustion heat inside that does not have its own draft air source (e.g. wood stove, non-sealed combustion unit heater/furnace), you will need to make sure you are getting enough make up air so you don't draw the heater exhaust back into the shop.

[Dan Chouinard]

Thank you for the replies. The collector is in an unheated space adjacent to shop. Shop heat is radiant in concrete floor. How much noise are we sending outside with the dust?
What kind of increased performance can we expect from cyclone bypassing the filter?

[Brice Rogers]

I have a 2 HP Harbor Fright that goes through a Thien baffle and then vents directly outside. I'm exhausting it through a 5" dryer vent with a flapper. The noise outside is not particularly noisy. It doesn't sound much louder than the hood fan over the stove. Also, because I'm venting outside, the noise in my shop isn't that irritating either.

But, I don't know your neighbor and space situation. If your vent is 10' from your neighbor's bedroom or patio, then maybe it could be somewhat of an issue in the warm weather when people have their windows open. How far away from the vent would your neighbor be?

[Jason Evans]

I've been considering this too. Besides temperature and humidity changes in the shop, which suck, I'm concerned about the fine dust that goes outside being sucked back in the shop. The air has to be made up somehow so imagine it'll be coming back in through the little cracks in the doors and windows. Maybe it'll just blow away, but on a still day when running the collector for a long time I could imagine it being a problem of the fine dust coming back in, which is the opposite result of why dust collection is needed.

[Doug Dawson]

You will be sending a lot of conditioned air outside and will have to condition the air replacing it... Heating in winter, cooling in summer...
Raises your utility costs and also comfort levels until incoming air is conditioned...

Hmm, let’s say you have a 700sf shop with 10ft ceilings, that’s 7000cf. And let’s say your dust collector is drawing 1000cfm. That roughly means that your dust collector is drawing all of the conditioned air in your shop to the outside every 7 minutes, which has to be replaced with outside air, which has to be reconditioned in 7 minutes, and so on. I’ve never figured out how this can be considered reasonable in anything but a room temperature/humidity outdoor climate.

[Jim Becker]

T How much noise are we sending outside with the dust?

As long as you direct the air flow downward a bit...say, a 45º angle toward the ground...the noise will not be passing "direct" toward anyone or anything. Direct sound is much noisier than indirect sound. That said, I will reiterate that exhausting outside will likely be noticeable in the winter with the level of airflow you will be pushing when the cyclone is running. Your radiant floor heating may or many not keep up with that level of air exchange.

What kind of increased performance can we expect from cyclone bypassing the filter?

Not "astronomical", but there will be a performance increase over caked filters for sure.

[Charlie Jones]

This works well in my small shop. It is only loud where the pipe comes out and in that direction. Everywhere else it puts out a low moan. There is no visible dust on the ground or on the vegetation near the pipe. I think the cyclone gets over ninety percent. It will suck your heat or air out eventually. It does fine for me. It was worth a little heat to get rid of those pesky filters. I am in North Carolina. Being as you are in a northern location, you might want to have a wye with a filter stack and use a blast gate to divert to inside on really cold days. The performance is noticeably increased.

[Tony Latham]

Mine is vented outside and I like it. It's not what I would call noisy outside. No accumulation of fines.

As other's have mentioned, the downside is bringing in hot or cold air.

But I like it here in Idaho.

T

[Dan Chouinard]

I really appreciate the feedback guys. Lots to consider. Perhaps outside venting is an overreaction to a one time event. That filter was stuffed nearly 100%. Exact cause unknown. Keeping a close eye on it for now. I can say for certain that filter cleaning sucks. Or does it blow?

[Kevin Jenness]

Cleaning filter canisters does suck. If you have room, bag filters with the same area are far easier to clean in the event of overflow.

The best simple setup I have seen for preventing overfilling and filter backup was a cyclone with a rotary airlock dropping into a dump trailer.

I would not vent outside in this climate, tempting though it is. My neighbor does. but his shop is cold and he is constantly switching the blower on and off to conserve heat. Your radiant setup will help, but still...

[Keith Outten]

No Bags, No Filters, No Hassle.
I have been exhausting chips and dust outside since the early 1980's.
Performance increase is excellent even with a very old 600 CFM collector.
Heat/Cooling loss is negligible in moderate temperatures. Reasonable on cold or hot days.
The building and machines have more influence on the temperature than the air.
Noise is not a problem even in an area with close neighbors.
The clothes dryer vent in the house is about the same noise level.
I have used plywood boxes to catch the chips and currently have a large steel tank.
I dumped right out into the yard for a couple of years.
Over a hundred people have visited my shop and experienced the efficiency of my dust collection system.

I used the same setup at Christopher Newport University when I ran the sign shop there, its still operating the same way today.
The CNC Router and laser engraver ran almost all day 5 days a week the five years I was the CNU sign maker.

[Jim Becker]

I really appreciate the feedback guys. Lots to consider. Perhaps outside venting is an overreaction to a one time event. That filter was stuffed nearly 100%. Exact cause unknown. Keeping a close eye on it for now. I can say for certain that filter cleaning sucks. Or does it blow?

A stuffed filter is generally caused by one of two things ... an air leak (even the tiniest one) between the cone and the bin and overfilling the bin.