my cyclone is makin me hot....

[Ryan Brucks]

Ok, if you are going to say that 2" + WC isn't going to increase air friction, there's really not anything worth debating. Clearly these systems all put out varying degrees of heat, you yourself found 0.8 degrees. I'm not sure why the fact that the industry doesn't focus on that seems to be any proof it doesn't happen. You used an exagerated 8degree temp rise (which you keep refusing to admit you are mis stating what Alan posted, he never said the air was 8F hotter in the exhaust) to say that if it was that much, you'd have to "accont for it".

well maybe that's true for industrial sized systems, but in shop environments, it doens't really matter what air density does after the cyclone. You have like what, 12" of ducting and then the filters afterwards? 99% of the pressure loss happens on the INTAKE side of the cyclone and in the cyclone itself. Wynn filters have a loss of like 0.2".

[Michael W. Clark]

This is my last post to this thread. My intent was only to let the OP know that he did not need 5HP worth of AC to keep up with his DC. My offer still stands to estimate shop heat loads based on data. If anyone wants to go throught the exercise for grins, start a new thread or PM me and I will be glad to contribute however I can.

Good Day.

[Ryan Brucks]

For my 23x20 shop, I got a window AC/heat with 17000 BTU cooling and 18000 BTU heat.


With my 1000w DC and 5hp table saw running my shop gets hot really fast unless I have the AC running. With the AC running it keeps up. I might be slightly over powered in the AC department but this causes me no issues. Why not get 5hp worth of AC? It's a mistake to follow standard BTU suggestions when there is so much heat generating machinery involved.

I am suggesting using data too. Data using the actual power consumption of the devices... not home made tests of energy rise that are misleading and meaningless for many reasons listed here.

[Alan Bienlein]

Okay I just went out and redid my test again and got an 8 degree rise in temp from the air coming out of the filters of my cyclone. I had 3 6" blast gates open. My system draws 18.5 amps with 3 gates open. I then proceeded to close all the blast gates and the body of my cyclone went from feeling cool to the touch to getting warm to the touch. The instant I opened a blast gate you could feel the hot air come out of the filters. All of this was within a 6 minute time period.

Also my temp rise stabilized at 8 degrees above the ambient shop temp of 78 degrees.

[Michael W. Clark]

I wasn't going to post again, but I see this as a point to find common ground.

Ryan, I'm assuming you have an above ground shop. I have a basement shop and don't see the heat gain with a 5HP saw and 1.5HP collector, but I'm surrounded by conditioned space and have some AC vents in my shop. My shop stays the same temp pretty much year round, actually colder in the summer.

I don't think your AC is that out of line for an above ground or stand-alone wood shop. If you convert 17000 Btu to HP, that's 6.6HP. You just covered your TS and DC (6.3 HP or 7 Hp nameplate). You still have to remove the heat gain from the ambient air outside the shop, lights, and any other miscellaneous heat sources. When the two motors are running and its hot outside you have more heat load than is installed by your theory. Granted the TS and DC don't run continuously, but your AC can also cycle. By your admission it has no trouble keeping up.

My point was that if in your shop you noticed the DC closet getting warm, I don't think you need to add another ton of AC such that you have 2.5 tons of AC on this size shop.

[Ryan Brucks]

I see where you are coming from. I apologize if my tone was a bit short in a previous post. You have always been cordial and helpful in other threads to me. Yea you got it right my shop is above ground and is totally isolated from the house HVAC. no vents except the AC.

[Neal Schlee]

....I have a 5 hp cyclone that I vent back into the shop. After 5-6 hours in the shop the air coming out of the cyclone closet is warm. The closet is designed so that the return air from the filters runs up through the top of the closet and then out so that the motor gets some airflow.
To others with cyclones: how hot does your cyclone run? Thanks!

Anytime you compress air it creates heat, and your cyclone compresses the air. Example your air compressor, the air coming from the pump is hotter, this is why many compressors run the air thru cooling tubes before it goes into the tank. I run a 20hp Roots blower on my CNC vac table. Many shops vent the heated exhaust air outdoors, I don't, it helps heat the shop in the winter (in Alaska).

Neal

[Ron Natalie]

Yes but when the compressed air expands it absorbs heat. This is the basis of your refrigeration system (fridge, heat pump, ac). Ideally, those two energy exchanges would exactly balance out except you'll be moving the heat from where it expands to where it is compressed.

However, that still doesn't change the fact that if you pump in 5000W-hours of energy into the room and there's no other air circulation or radiation going on (i.e., perfectly insulated, sealed up), you've added 17,000 BTU's to the room when all is said and done. Mike can doubt it all he wants, but you can't beat simple thermodynamics, and it is who we in the facilities industry have sized computer room air conditioners and the like for many decades.

[Jeff Duncan]

This thread is way over my head....all I want to add is a couple "average guy" observations...

First I run a 7-1/2 hp cyclone, when it runs the motor fan pushes a LOT of warm air down into the shop. A 7-1/2 hp motor apparently creates a lot of heat b/c it is a noticeable flow of warm air downward. Add to this the fact that it is blowing down from the highest point in the shop, and the one thing I do know is heat rises

Second, (without going to deeply into Laws I don't understand maybe someone can confirm or deny this one)....my systems piping is run along the ceiling and the cyclone itself is pretty high off the ground. Since heat rises my ductwork and cyclone, (especially the cyclone as it's being heated up by the motor fan from above), are going to be warmer than the inlets where the air enters....generally within a couple feet of the ground. So wouldn't the air passing through the warmer duct and cyclone gain some of that heat and expel it through the outlet, (filters)? To a layman it seems like it would....but who knows???

So if the OP has a cyclone in a closet, the heat generated from a 5hp motor simply running is going to heat up that closet a good amount. This heat is going to want to escape outwards. Would some of it not make it's way out by transferring into the air stream though the ductwork and out the filters? Making a good case for not only directing the exhaust air out, but possibly installing an exhaust fan in the closet to dump air heated by the motor outside also?

JeffD

[Ryan Mooney]

Yikes and I thought I went overly nerdy on some topics, nicely done all

On a practical solution side if/when I upgrade my DC so its relevant I'm with Jeff on these questions:
- how much heat could we avoid by "vent boxing" the motor and using a fan to blow that outside (assuming we have noise/pollution/sad neighbor reasons to not just push the waste air out).
- if we vent the waste air, are we still getting sufficient heat from the motor/impeller/cyclone/whatever such that we would still want to independently box and vent that.

This thread is way over my head....all I want to add is a couple "average guy" observations...

So if the OP has a cyclone in a closet, the heat generated from a 5hp motor simply running is going to heat up that closet a good amount. This heat is going to want to escape outwards. Would some of it not make it's way out by transferring into the air stream though the ductwork and out the filters? Making a good case for not only directing the exhaust air out, but possibly installing an exhaust fan in the closet to dump air heated by the motor outside also?

JeffD

[Ole Anderson]

With all of this being said, I am surprised that anyone runs a big DC long enough in their shop (hobbyist, not commercial) to heat it up enough to make a difference. Wait, I remember getting hot in the shop, I just thought it was my work that was heating things up. Hmm... Might have to rethink that.

[Carl Beckett]

- how much heat could we avoid by "vent boxing" the motor and using a fan to blow that outside (assuming we have noise/pollution/sad neighbor reasons to not just push the waste air out).

This would make a big difference Ryan. By putting the motor, and the blower itself in a box and pulling in air over this and pushing it outside, you take away any of the heat that is due to the losses in these two items (which in my opinion, are the majority of the losses). Any energy coming off these components would go outside and not into the shop. A good idea.

- if we vent the waste air, are we still getting sufficient heat from the motor/impeller/cyclone/whatever such that we would still want to independently box and vent that.

Exhaust of the cyclone air itself would pull away much of the heat due to friction and air movement losses. People are reporting that the air coming out of their filters is warmer than the ambient shop air - this means energy going into it - so this energy would be dumped to the outside if you vent to the outside. Much of the debate here stems from the question of just what overall % this is....

Both very viable and practical suggestions. (remember, these might work against you in the winter when you want heat INTO the shop)

Also note that the biggest determinant of heating/cooling need is the insulation of your shop (if your shop is poorly insulated and underground, it will dissipate heat faster and not increase temp - if its well insulated, then any heat going in will increase temp more quickly). There is a separate thread about calculating this.