the TRUTH about the water
vacuumkid:
The whole thing about positive and negative charges to water and dirt is hooey.
Want to know the truth?
The rainbow is bringing air from the room into the water bath, where the air mixes with water. The air is separated from the water by the separator, allowing only a certain amount of 'humidity' to the stream of air getting through. What happens is VERY SIMPLE. Even kids understand it.
The air in the room is DRIER than the water in the pan. As the dry room air mixes with the water, and is then separated, the level of water in the pan DECREASES. The rainbow EVAPORATES about 2 1/2 cups of water per hour on High speed.
While the water is CLEAN, that's fine. It's clean water evaporating.
BUT, when the water is DIRTY, it's dirty water being evaporated. AND, this is FORCED EVAPORATION of the water, like pointing a fan at a bowl of water. NOT, natural evaporation. Do the dirt, which IS in the water, comes through the separator with the humidity. A certain percentage of the total dirt in solution, is ALWAYS leaving the pan. On the old models (pre E Series), this dust triumphantly escaped the machine. The fact that this amount was SO MUCH LESS than what escaped through cloth vacuum bags gave the rexair (and rainbow) machines their 'supposed' air cleaning ability - since MUCH LESS dirt escaped the Rexair than the Hoover 150.
Fill the rainbow with a MEASURED amount of water. Leave the hose OFF and run the machine for 1 hour. Measure the remaining water. The variation will come with how dry the room air is. In winter, rainbows evaporate much MORE water (dirty water, remember) than they do in the humid summer time.
The real problem is that people clean WAY, WAY too long with one filling of water. The water should be changed once every ten minutes or so, when using the power nozzle. After that time, the saturation of the water is such that a LOT of dust is being evaporated with the water.
While I personally like the Rainbow and use one (sometimes - when the mood takes me) to clean my home, I DO take care of my machine, and the motor is still clean and bright like new.
BUT, the customers of my store bring in their Rainbows which are used as their ONLY vacuum cleaner, and the motors are always full of mud and dirt, the bearings bag, etc. I make a good living fixing Rainbows, as I run an authorized service center and I buy my parts directly from the manufacturer. The average service ticket on a Rainbow 'clean and service' is $150.