Reply
Thread Tools Display Modes
#1
Old 10-05-2009, 05:23 PM
Guest
Join Date: Jan 2000
Location: left coast (for now)
Posts: 1,903
Rainbow vacuum / air purifier

Does anyone have any experience with these? Apparently they are the only vacuums with a water filter, so no clogs or drop in efficiency.
#2
Old 10-05-2009, 05:58 PM
Guest
Join Date: Jan 2000
Posts: 762
I love mine. It is very efficient, not difficult to set up, and really does reduce the amount of dust in the house. My blue area rug was perceptibly brighter after the first time I used it. They are expensive, but IMO well worth it.
#3
Old 10-05-2009, 06:03 PM
Charter Member
Join Date: Sep 2002
Location: Wilds of WV
Posts: 10,652
If I didn't have (and love) my Dyson, I'd totally consider buying a Rainbow. But I would never buy it from one of those aggravating folks who come to your door to "demonstrate" it and then give you a hard-sell. If you want one, you can buy it a lot cheaper off of eBay, and without the hard-sales pitch!
#4
Old 10-05-2009, 09:28 PM
Guest
Join Date: May 2000
Location: Indianpolis, IN
Posts: 268
and water filtration is good...why?

I had neighbor with a Rainbow vacuum who could get an attachment if they got someone to listen to the pitch... we took one for the team and sat through the show. Ouch. You'd think these things could save the world.

The part that bothered me the most was the emphasis on the water filtration. Having worked with industrial ceramic powder manufacturing I spent a lot of time spec-ing dust collectors and filtration systems. I had to install a water based filtration system once (the air I was filtering was from an industrial dryer and therefore very moist). Dust collection efficiency numbers in the 50% - 60% range. The problem is contact. How to get ALL of the dust in the air in contact with the water. Picture a large volume of air moving through water....bubbles. Inside the bubbles....dust. The mechanics of generating turbulence is complicated. A re0usable Gore-Tex (or similar) filter membrane is, by far, the best filtration method.

and one more thing... water loses it's filtering efficiency as it get dirty...membrane filter get more efficient as the fill up. Air flow drops, but filtration efficiency goes up.

I believe the Dyson testimonial....skip the Rainbow.

Last edited by TheBori; 10-05-2009 at 09:28 PM.
#5
Old 10-05-2009, 09:35 PM
Charter Member
Join Date: Jun 2003
Location: Portlandia
Posts: 39,906
Consumer Digest is your friend. Do your homework before spending that kind of money.
#6
Old 10-05-2009, 09:47 PM
Guest
Join Date: Apr 2003
Location: Dayton Ohio USA
Posts: 27,499
Quote:
Originally Posted by TheBori View Post
I had neighbor with a Rainbow vacuum who could get an attachment if they got someone to listen to the pitch... we took one for the team and sat through the show. Ouch. You'd think these things could save the world.

The part that bothered me the most was the emphasis on the water filtration. Having worked with industrial ceramic powder manufacturing I spent a lot of time spec-ing dust collectors and filtration systems. I had to install a water based filtration system once (the air I was filtering was from an industrial dryer and therefore very moist). Dust collection efficiency numbers in the 50% - 60% range. The problem is contact. How to get ALL of the dust in the air in contact with the water. Picture a large volume of air moving through water....bubbles. Inside the bubbles....dust. The mechanics of generating turbulence is complicated. A re0usable Gore-Tex (or similar) filter membrane is, by far, the best filtration method.

and one more thing... water loses it's filtering efficiency as it get dirty...membrane filter get more efficient as the fill up. Air flow drops, but filtration efficiency goes up.

I believe the Dyson testimonial....skip the Rainbow.
You're describing a bong pipe.
#7
Old 10-05-2009, 11:34 PM
Guest
Join Date: Oct 2008
Location: San Jose, CA
Posts: 3,828
We had one a number of years ago. Great unit, one of the best vacumns that I used. But it did require a lot of maintenance.
#8
Old 10-06-2009, 07:24 AM
Guest
Join Date: Jan 2000
Location: left coast (for now)
Posts: 1,903
TheBori- filter efficiency might go up, but you get less air flow, so less dirt gets picked up.
#9
Old 10-09-2009, 05:17 PM
Charter Member
Join Date: Jan 2001
Location: Mid Atlantic, USA
Posts: 9,115
Quote:
Originally Posted by TheBori View Post
Dust collection efficiency numbers in the 50% - 60% range. The problem is contact. How to get ALL of the dust in the air in contact with the water.
This is right. I spent about 15 years in the development of filters and in aerosol science (meaning particles in air, not the propellant cans). It is pretty easy to do a practically perfect job of catching particles with a filter, and a vacuum cleaner is a pretty easy place to do it. There are several very different ways of catching particles, one of which is the water. I did see a useful application of the water method in those motorcycle-like or snowmobile-like boats people race around on, in which water keeps getting sucked into the engine air, which is hard to handle in a filter, so they used the water to their advantage anyway. But except for some very special nich applications, these water based cleaners are not much use - especially in a vacuum cleaner.
#10
Old 10-09-2009, 08:42 PM
Guest
Join Date: Aug 2009
Location: East of East St Louis
Posts: 513
If you have termites, and it's spring and they're all over the place...the water filtration thingy works really well.



not recommended as a substitute for actual professional extermination purposes

Last edited by Magicicada; 10-09-2009 at 08:43 PM.
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:59 AM.

Send questions for Cecil Adams to: [email protected]

Send comments about this website to:

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Copyright 2018 STM Reader, LLC.

Copyright © 2017
Best Topics: warship names the ramones suck seminal work ck2 bastard eunuchs questions lion vs bear kfc mass yellow coward paystubs adp wolf chihuahua hybrid eyeball puns roaches mating excel if negative then zero why do black people have white feet steam radiator valve open or closed new york mining disaster 1941 bee gees stop signs in france doorknob fell off can't open door what do japanese think of ww2 how to find leak in air mattress what does juicy fruit taste like rush hour traffic chicago patricia arquette breast implants elephant story tim conway 6 finger guitar player