Direct air motor vs Clean air motors

[sprockkets]

I think the only reason, if any, why a direct air will pick up more is because the static pressure is greater than a bypass at the nozzle. Sounds obvious, but I can't explain why that should be the case. Think about it - each has to pass air through bags so the net result should be the same since the direct air will be up against the rest of the hose/duct work, thus it really shouldn't matter where the motor is.

In any case, I don't think the small, if any advantage of a direct cleaner outweighs the fact that I can pick up paper clips or small metal debris left behind and not worry about it messing up the impeller fan. I'd never use a direct air vacuum to suck up all the salt and sand that comes during winter.

 

[sptyks]

Sprockkets: I guess you never heard that it is a fact that the greater the distance the fan is from the carpet, the more airflow and suction you loose. 


 


Look at the Direct Air Royal, Kirby and the older Hoover Convertibles. Their performance is excellent and they only need a 350 to 500 watt motor to do it. Why? Because the motor and fan is only 3 to 4 inches from the carpet where airflow is at maximum.


 


Now take a look at your typical Bypass air machine. The motor and fan is 3 to 4 feet of internal piping and external hose from the carpet, therefore airflow is greatly reduced. And <span style="font-size: 12pt;">we all know that it is Airflow, Agitation and Suction (in that order) that cleans carpet the best.</span><span style="font-size: 12pt;">This is why most Bypass sair vacuums need a 1000 - 1440 watt motor, a</span><span style="font-size: 12pt;">nd the performance is still less than a Direct Air machine will provide. </span>


 


<span style="font-size: 12pt;">Check out the link below for a better explanation:</span>  


 



http://https//www.youtube.com/watch?v=hGMrZZaTRSE

 

[sprockkets]

And a direct vacuum still has all that piping as well to deal with on the other end. It's the same problem, as that motor has to fight that resistance as well.

The best way to mitigate that is what sebo did, which is keep right angle turns to a minimum to none, keep the bends at nice angles and use top fill bags instead of feeding it from the back at the top shooting and clogging with dirt at the top.

As far as your energy or watts argument, that's due to marketing departments. A sebo from sometime ago used only 850 watts, and only increased it due to customers thinking it made a difference. And now they are going back to it thanks to the EU. I'd wager the extra watts overcome the extra filtration direct vacuums lack. And olive here already showed that 700w vs 1000w motor in the Felix worked just as well with much less wasted energy as heat.

Third, that link you shared proves nothing. That Eureka machine is a great example of a crappy vacuum. Having the suction on the right isn't a bypass feature by any means, as Sebo has the inlet more toward to the middle and not on one side. And we all know how poorly a dyson agitates for sure with such a weak dinky roller. And I also have an older Hoover direct air and Oreck XL that clean much less than my bypass vacs. And another benefit to not having such an agressive agitation is you aren't destroying your carpet. Far more important is proper height adjustment which those old vacs have and most don't.

Now I'm not going to say that Royal or Kirby vacuum sucks either, cause it doesn't. But let's also not forget the only sane way of buying a Kirby is second hand, because I'm not going to pay thousands for such a archaic vacuum through a annoying salesman.

 

[marcusprit]

How poorly Dyson agitates? You need to watch this video I think it will change your mind.

 

[sprockkets]

They've gotten a little better. But that one in the video posted earlier is what my dad has, and it barely has any bristles to it. At least it came off easily to clear a clog on it from having such a small inlet

Problem I see with that one is what happens when the floor head floats on the carpet.

 

[marcusprit]

Well I have that Dyson and I can tell you it does a fantastic job I'm very impressed with it. And I've owned some very good uprights including Miele S7 , Sebo Felix and Kirby Diamond.

 

[sprockkets]

I've read the rather lively debates marcus

I try to not be a dyson hater, but I can't let their 20 years of "Never loses suction" just go by while they now say, "No, really, we mean it *this* time!" They don't really mention that their older non cinetic designs fall into that category. They are really the apple of vacuums.

Since I have to use vacuums for work, I'm now biased to any vacuum that is well built for the job.

@sptyks if I could reword my post, I should add, you are right, but possibly for more than just the direct air part

 

[marcusprit]

Haha hope you enjoyed them Joe So what cleaner do you use at work?

 

[sprockkets]

Right now? A Hoover Windtunnel Air. It's only had two bottom plates, one motor, one repair to the floor brush sensor replaced.

I'm not trying to knock it either cause it wasn't meant for abuse. Otherwise I use a Riccar for work. Better built but still wish it was the commerical model.

Since I found out about Sebo/Windsor sometime ago I'm trying to get one myself, if that Felix ever arrives Otherwise I've used a few at my church who bought an Axcess and the dual motor Windsor.

 

[marcusprit]

I've tried out a Riccar Brilliance and was VERY impressed with it. Sadly we don't have them over here.

I love my Felix and have been considering an X4 or G1. I think for bagged uprights Sebo is the best you can get in Europe. I would like to see a new domestic upright though I think it's overdue

 

[sptyks]

Sprockkets: You are dead wrong when it comes to your opinion that Direct Air vacuums and Bypass Air vacuums have the same amount of airflow no matter how far the fan is from the carpet. A Direct Air Vacuum has at least 5 times more airflow than a Bypass Air machine and I have proven it with my own Baird Airflow meter:


 


If I remove the floor nozzle from my Kirby Sentria and connect the Baird meter directly to the fancase opening where the meter is only 1 inch from the fan, the airflow pegs the meter at a "10".  Now if I remove the Baird meter and attach the 6 foot hose instead and then attach the Baird Meter to the end of the hose, I get a reading of m"7" on the meter.


 


Now if I disconnect the hose from the floor head of my Hoover WindTunnel Air, and attach the Baird meter to the end of that hose I get a reading of "2" on the Baird meter. Now how do you explain that?


 


Click the link to read an article published by "Goodvacs" performing airflow testing on a Kirby and a Dyson using the Baird meter:



http://www.ebay.com/gds/Best-Vacuum-Buying-Guide-/10000000003855053/g.html

 

[marcusprit]

I know what I'd like to do with your Baird Meter! Haha

 

[sptyks]

Marcus, I bet you want to smash it to smitherines.


 

 

[kirbysthebest]

MARCUS

Five minutes on the Naughty Step.

We do not smash other people's property.

 

[marcusprit]

No I was thinking of sticking it where the sun don't shine

 

[kirbysthebest]

Well Then

10 Minutes on the Naughty Step.

 

[marcusprit]

Hahahaha ))

 

[sprockkets]

@sptyks

You've linked me to a site with no pictures showing up.

"You are dead wrong when it comes to your opinion that Direct Air vacuums and Bypass Air vacuums have the same amount of airflow no matter how far the fan is from the carpet. A Direct Air Vacuum has at least 5 times more airflow than a Bypass Air machine and I have proven it with my own Baird Airflow meter."

A baird airflow meter is an arbitrary form of measurement. I have tools that can measure proper suction in inches of water column or CFM.

But you still are concluding you are right on a very small set of vacuums.

"If I remove the floor nozzle from my Kirby Sentria and connect the Baird meter directly to the fancase opening where the meter is only 1 inch from the fan, the airflow pegs the meter at a "10". Now if I remove the Baird meter and attach the 6 foot hose instead and then attach the Baird Meter to the end of the hose, I get a reading of m"7" on the meter."

Which means still nothing because we aren't really measuring anything in proper measurements. Is that 30% less airflow? Or did only the static pressure change? Does it actually affect performance?

I'm very well aware of what happens when adding any form of restrictions that air flow will go down, seeing how I do HVAC stuff. That still doesn't prove that is the sole reason why a Kirby is better.

"Now if I disconnect the hose from the floor head of my Hoover WindTunnel Air, and attach the Baird meter to the end of that hose I get a reading of "2" on the Baird meter. Now how do you explain that?"

A Windtunnel Air doesn't have great suction to begin with seeing how it has to pass air through a cyclone setup, has two right angle bends in the ductwork, a pre filter, a crappy chinese motor with small openings for air exhaust, a foam filter surrounding the motor including the exhaust, a black material to prevent you from seeing the motor on the holes, to a final filter. How do I know that? I took one apart when the motor went.

Again, the reasons why a Kirby has such great air flow isn't exclusive to them or only possible via direct air. And for me, the advantage of having a quick easy to use hose immediately outweighs any benefits a kirby has.

Heck, an Atrix Mighty mouth has the intake, direct to a bag, then the fan. No hoses here. That's almost as direct as you can get without worrying about the motor fan processing bolts and screws, which is what that vacuum is designed to suck up.

 

[sptyks]

Sprockkets, I'm afraid that you are still wrong. It seems you are confused and believe that suction and airflow are the same thing. They are not. In order to clean carpet really well you need 3 things:


                                 (1) Airflow


                                 (2) Agitation


                                 (3) Suction


 


In that exact order! If you had a bypass air vacuum that could pull 100 inches of water but can pull only a 3 on the Baird meter, it has poor airflow, and it will not clean nearly as well as a Direct Air vacuum. The Baird meter measures Airflow and that is what's most important.


 


This video shows the Royal all metal Direct Air vacuum vs three expensive bypass air vacs.  Airflow wins all 3 battles here:


 


 





 

 

[kirbysthebest]

My Horsey died so I promised to quit beating it

But I still have a couple of whacks left in me. 


 


Don't forget also that the design of the nozzle contributes to the effectiveness of the direct air uprights.  


 


Two that are referenced previously are the Royal and Kirby.  Both use a bell shaped nozzle that employs the Bernoulii principle where the speed of the air is multiplied from nozzle to fan, so to measure at the fan case is defeating part of the design.  This is where your suction portion of the airflow equation comes in. 


 


Poor horsey.  Whack!! Whack!!!