Is it better for a vacuum to run on slower or faster speed?

[fan-of-fans]

I have a Kenmore Progressive canister that's variable speed. Usually I keep it on the lowest setting for doing dusting or hard floor vacuuming, because it seems to pick up just fine on that speed.

I usually use the higher speed for when I use the power nozzle on carpets or sometimes in the car.

My thinking is it's probably better on the bearings since it's running slower, especially with these newer single stage motors, that I hear run higher RPMs than the older Ametek 2 stages.

On the other hand, I'm wondering if maybe the motor is actually running hotter due to less air flowing.

I sort of do the same thing with my Kenmore Progressive upright too which has a 3 speed motor, although sometimes I use it on Inteli-clean which auto-shifts the speeds depending on the amount of dirt being sensed.

 

[vaclab]

Overheating At Low Speeds Is A Myth

Think of continuously variable speed canisters (or uprights). Some users run them on low speed for hours with no issues year after year.

Generally speaking, a properly working electric motor generates less heat at less RPM so it should even last longer running at lower speeds.

Want some measured proof? See the myth busted below.

Bill

The Kirby Diamond Edition Overheating Myth

 

[vacuumdevil]

@fan-of-fan
Man you're not the first person to ask this question. this really opens up quite the can of worms for debate.

My understanding as you are correct on it putting lost where on the bearings of the motor. You are putting off more where the speed control mechanism.
Which varies greatly depending on the vacuum. Sometimes that extra heat from stepping down the electricity goes into the motor coil. Some machinees use circuitry to accomplish this. Depending on the build quality this can affect it those components.
I'm sure if the machine is built to high standards it doesn't cause any harm one way or the other. The question is which machines are built to those higher standards?

I will say using a dusting brush when on a lower power setting usually keeps the bristles from getting deformed.

I would also say for floor pick up I'm really satisfied with a portable machines power and always want more power. Personal preference.

 

[jayelux]

Low Speed

Roseanne Barr once rhetorically asked why a vacuum would have a low speed option--"for the days when you want to do a shitty job?"

 

[gottahaveahoove]

Well, I (personally)doubt

"Roseanne Barr" would be an expert. I also doubt she vacuums.
Hoover cleaners (some) have a "power surge". The Convertibles also "shift" to more power for other jobs. Some people have re-wired them to stay on "high". Others insert an object (wood, etc) to them on "high". I don't think that's necessary These cleaners, well the good, vintage ones, were designed to perform their jobs. Just like attachment strength, how much power do you NEED?

 

[dysonman1]

The Hoover Company put out a wonderful brochure in the early 1920's entitled "How to choose an electric cleaner". One of the selling points of the Hoover was that the motor ran slower than other cleaners. They pointed out that the wear to a motor is proportionate to the cube of its speed and that the faster running motors actually wear out 8 times as fast as the slower Hoover motor. They were referring to the Royal, Eureka, and other straight suction cleaners with their fast running motors that were not driving a brush roll. The Hoover Company was certainly correct in that their motors almost never wore out. Today, motors are made in China even for Hoover and all wear out at about 150 hours, except of course for motors like Rainbow or Kirby or Miele use.

 

[gottahaveahoove]

I have a model 69, for instance, which

belonged to the late Glen Deinst. It had the wires reversed, to run on high constantly.
I had it returned to it's original state.
There really is no need to run these machines on high constantly.

 

[tseg]

I'm in my 50's and I don't think I ever recall having a vacuum motor wear out on me, but I know it happens, particularly if one vacuums for a living. Brands I've used have been Hoover, Dyson, Panasonic, Miele and Sebo. I've thrown out and passed on a few vacuums in my day, but usually that is because a number of other bits on the machine have given up the ghost. The same thing goes for my vehicles, which I frequently keep for over 10 years (knock on wood). The motor is fine (use synthetic oil) as the wheels fall off.

With the above said, Miele automatic vac motors run at their highest RPM on hard floors. I note the U1 whose motor automatically drops a notch in speed when turning on the roller. Their C3 automatic vac motor systems will slow as pressure builds. I assume a straining motor creates even more wear and energy use than a fast moving motor.

Not that Germans are known for over-engineering, but if I observe the result of German corporate research applied to their equipment, I'll take that signal over over a layman's gut instinct, no offense to anyone.

In summary, high speed for hard floors, lower speed for carpets, which makes sense since in hard floor mode without a roller operating, air flow has to do just about all the work.

 

[jo]

Stress on a motor will wear it out faster. Clogged filters and other clogs will do this. A motor needs the air passing through it to cool it, add the stress of a clog of any sort and the motor is forced to work harder which generates added heat and now coupled with less airflow really gives most of the motor parts a real beating quickly shortening it’s life. And some motors are just “defective” from the get go having “running hot” issues. Not sure what this is caused by but obviously this is a problem.

Running a motor on the high speed may help the machine to clean better and deeper on carpet and if that’s what’s needed, even if it adds stress then the machine is performing well but at the possible expense of motor wear.

Consumers of bagged vacuums often think they should pack the bags full to save money but the dirt cuts off suction causing motor stress and heat buildup and also reduced cleaning efficiency, bags should be changed when 2/3 full. Bagless vacuums should be emptied before or just before the dirt reaches the full line to reduce filter clogging and filters should be washed monthly to maintain peak performance of the machine and extend motor life.

Yes I sound like the printing on a vacuum bag or in a manual but the reason is clear, studies have shown that adding stress from clogging to a motor shortens it’s life because it’s the stress itself which creates heat buildup AND as a result of the stress more heat is built up than normal plus now with the clog you now have less air passing through to cool it at a time when under this stress it would actually be needing MORE air to cool it to offset the additional heat buildup.

Multi speed vacuums to me were designed for low speed to be used for things like vacuuming drapes lampshades and other more delicate things where too powerful of a vacuum could do damage to the item or the vacuum could “stick” to the item too much so to move it. But usually the sticking is a problem of the nozzle itself not having a proper airflow pattern around edges.

In the case of my Shark rocket it has two speeds but that only controls the brush roll...low speed for hard floors so dirt doesn’t get flung around and shot out the back instead a gentle sweep up motion with full suction and also the low speed is good for little mats and area rugs that might otherwise get yanked up by the high speed brush. The motor in it seems to be smart, increasing power if the brush stalls for a few seconds to see if it will get it going but if it doesn’t the overheat switch stops it and light comes on red so as not to overheat itself and alert the user that I need to reset it. Smart and an indicator of quality I think to include these features which no doubt will extend the motors life in the power head.

 

[vacuumdevil]

@tseg If you're Miele u1 is under warranty you should have the handle replaced so it doesn't drop down when you turn the brush on. It's not supposed to do that . They changed switch manufacturers and that was the result of that.

 

[lesinutah]

Old

I have a 1973 or 76 300 or 400 amp royal.
It rotates slower obviously since it has less power. You adjust the height adjustment it picks up as good as any vacuum.
If you turned on a small 4 inch box fan it's quieter. It rivals my electrostatic push vacuum noise wise.
I did have a 1030z and have a 4000 10 amp and 10.5 motors respectively. They aroud but suck up too much. You get a stuffed animal near it gone in the blender.
The electrolux oxygen 3 and riccar with suction increase and decrease feature are quiet.
High and low doesn't matter they suck.
Straight suction do too.
Les

 

[tseg]

@vacuuumdevil: "@tseg If you're Miele u1 is under warranty you should have the handle replaced so it doesn't drop down when you turn the brush on. It's not supposed to do that . They changed switch manufacturers and that was the result of that"

^^^^ Funny you mention this. I bought my U1 used a few years back and it had the old style round buttons, where one flipped vertically and the other flipped horizontally. I noticed this motor slowdown and sent a note to Miele (it may have even been per your recommendation at the time). Miele was actually kind enough to respond and immediately send me a new modern handle with the 2 rectangular buttons that turn on horizontally without further questions asked. After the swap, there literally was no change how the motor operated, so I assumed this was supposed to be the case. I've seen other posts reporting similar.