X-10 Home Automation | Web Site Tricks & Tips | Personal Security Products, Air Tasers, Stunguns
The higher the altitude the
more sealed vacuum you will need,
(you loose sealed vacuum as you raise in altitude). Sealed vacuum in a
central vacuum is the "strength of pull", needed for pulling uphill and
bulky heavy items.
Air flow is needed for moving the dirt. The more air flow the more volume of dirt that can be moved. Air flow is lost do to with resistance, (longer distance to power unit) and leaks. Air flow is what causes the dirt to "jump" into the vacuum wand without touching it. Once in the hose or pipe both CFM and water lift come into play. There is a balance between them in a central vacuum system. One is not more important than the other. Sealed vacuum is what you feel when you cover up the end with your hand. Demonstrating the vacuum by picking up a lead weight is a gimmick and is not indication of how will the vacuum will pick up dirt. You do not vacuum with it sealed, that makes air flow to zero! A scientific paper could be researched and written of a comparison of CFM and water lift and ability to clean in various types of vacuums, central, upright, shop sawdust vacuums, portable shop vac, etc. kw
A trick to show that sealed vacuum
is not everything is to poke a
pin hole in a business card put the card over the opening an a vacuum
gauge over hole in the card. to measure the sealed vacuum. The sealed
vacuum will be maximum! You cannot vacuum through a pin hole!
Look at the sealed vacuum and air flow (same size opening) of the units to compare vacuum power. One 2 HP motor have more vacuum/suction power that another 2 hp motor because it is more efficent. Air watts is helpful by not by it's self as long as everyone is calculating it the same way. This may seem like a obvious thing but it not necessarily so. Until a number of years ago music amplifiers and speaker power ratings were not standardized. It took law suits to get the industry to standardize. They used every trick to make their equipment seem more powerful than it was. For instance 100 watt speakers. They could be two 50 watt peek to peek power, peek power or music power. (each company defined this rating). RMS power is the true power rating now the Federal standard.
PVC solvent glue and MEK are toxic and flammable, keep them
out of the reach of children. MEK can be found in most hardware
stores. There is PVC glue that will work wet. It is more
expensive and I have only seen it for professionals in large cans.