So you have read about which central vacuum is best and now you
are doing your homework to find the best central vacuum for you - great! Below are the various methods of filtration and collection of central vacuum in no particular order. When you need to find which method of collection and filtration a particular model uses just browse our central vacuum power units category page which shows performance specifications and sizing along with the collection/filtration system of each model in the quick-specs section.
Bagless: Permanently Filtered
The most common method of production and one of the most widely used methods of filtration in CVS. This design has a permanently installed cloth filter in the vacuum unit that separates the incoming debris-laden air and collection system (dirty side) from the motor and exhausting air (clean side). Dirty air pulled into the central vacuum power unit is suction ed through the cloth filter. The dirty side of the cloth filter stops particles on the surface, allowing the cleaned air to pass though.
Just like the furnace filter in your home's heating/cooling system, dirt and debris collect on the outside of the filter and the suction motor is protected from damage. This permanent filter is maintained by a mechanical flexing action which is part of the filters design that helps it to shed the filtered debris into the collection bin below for emptying by the user. Some dealers and installers prefer this type of filtration since the limiting design helps to protect the power unit's motor from a person unaware of the vacuum system or how full the collection bin may be. This method is quite simple and very fool proof but the permanent filter limits the performance of this system and there may be additional maintenance required.
The Good. Simple Design, Available in Many Models, Great Motor Protection.
Not So Good. Lower Performance, Messy to Empty & Maintain, Filter Retains Odors, Limited Installation Locations.
Central Cleaning Systems used today are descendants of commercial units used at the beginning of the last century. Based in large part on the technology available at that time, commercial central vacuum systems were bagless and used large dump-out barrel sized collection bins. Later in the 1950's when large-scale production of residential central cleaning systems began, the existing commercial designs were scaled down for home use. The history of central cleaning helps to explain why a majority of CVS's in use today are bagless permanently filtered units. Though technology has rapidly advanced and the central vacuum systems built today are more similar in principal than in component to those early residential central vacuums, our industry's addiction to promoting bagless vacuums persists.
The bagless design is advantageous in its low-tech approach to filtering. With a filter always in the vacuum system that will not be removed or affected by user operations, the design enjoys a long life. There are two less desirable factors for the actual owner/user of a bagless central vacuum power unit that impact performance and usage of the equipment. The permanent filter system is just that, permanent. This filter is never removed from the vacuum system and is not designed to be economically replaced. While the mechanical action does shed the majority of debris from the filter a good amount remains behind. What does remain behind on the filter is most often ultra fine particles that clog the pores of the permanent filter and slow down the airflow thereby reducing the vacuum system's performance.
How much suction can you lose in a bagless central vacuum? Depending on the filter material and debris being cleaned you can lose 50% or more of a new vacuum's suction with just a small amount of debris in the vacuum's collection bin. In one study a bagless vacuum dropped to just 44% of original performance after cleaning the equivalent of three rooms in a home. Even completely clean filters can create a pressure drop in a vacuum system and reduce airflow of the suction motor by 15% - 20%. All vacuum filters slow the airflow and thereby decrease performance; this is to be expected because this is how the debris is removed from the vacuum stream. But how much of a decrease varies. All residential central vacuums have filters, even those "filterless" models.
The second area of concern for bagless central vacuums is the collection system. Dirt, dust, debris and allergens vacuumed from your home are collected into the debris bin where they sit until emptied. For some of us with a shop-type vacuum this is a familiar task. A large bin full of dust and dirt, and a large filter that hangs inside the vacuum. Bagless vacuums have limited installation applications and the power unit should be installed in the garage or unfinished area. Emptying a bagless central vacuum can result in dust released into the air when you dump out the collection bin and dirt falling onto the floor when the collection bin is removed.
HYBRID Collection Systems
Not sure which is better for your application, bagless or bagged? HYBRID Collection Systems might be right for you. HYBRID systems are built in the same basic design as a permanently filtered vacuum unit with some modifications to the intake system and occasionally a change to the filter media system. A HYBRID system is one which can be used with a sealed disposable bag or as a traditional bagless dump-out collection system. HYBRID systems leave the collection choice up to you and the system can be changed from one collection style to the other as needed. When bagless the HYBRID system functions as any regular permanently filtered power unit with a self cleaning filter to separate the incoming debris from the air. When used in bag mode the HYBRID system provides hygienic collection of vacuumed debris inside a sealed closed top bag. When the bag is full you simply toss it and install a new bag.
The Good. Simple Design, Excellent Motor Protection, Choice of Collection Systems, Hygienic Maintenance in Bag Mode, Great for many Installation Locations.
Not So Good. Lower Performance in Bagless Mode, Cost Of Bags (est $15-$20/YR.)
HYBRID vacuum systems have nothing to do with "going green", HYBRID is about choice. Central vacuum consumers have changed in the last 60 years and central vacuum manufacturers are working hard to catch up. While only a few bag-only central vacuums make it to market, many vacuum manufacturers are embracing the HYBRID vacuum as a way to satisfy many new home owners who want the clean and convenient maintenance of a bagged system while still producing a vacuum system that will be accepted by the dump-out crowd. While most HYBRID users will only clean with their vacuum system in one configuration or the other, some central cleaners will change their HYBRID system as their condition or need changes.
The advantage of HYBRID over a bag only style is additional safety. Though the permanent filter of a HYBRID vacuum does not provide any actual filtering when used with a disposable bag, the permanent filter is always in place and should a bag be misinstalled or not installed at all the permanent filter will provide filtration and motor protection. With the advanced synthetic bags the HYBRID vacuum makes for an excellent collection system where you need to sort through the collected debris or when you need to clean fine particulate including spilled powders or ash that would normally damage the permanent filter of a conventional bagless vacuum. The HYBRID permanent filter also provides you backup cleaning capability should you unexpectedly run out of disposable bags.
All HYBRID vacuums use disposable closed top or sealed bags and feature a locking collar or gasket that prevents dirt and dust from leaking around the disposable container. Just as with portable vacuum cleaner, using a central vacuum system with a disposable collection bag is simple and easy to maintain with no dustbin puff-back or particulate float. Replacing a disposable bag is not only more hygienic than dumping a bin full of vacuumed debris but also reduces the odors and increases the vacuum system's performance. Each time you replace your full vacuum bag you have also reset your vacuums primary filter performance. This short filter cycle will provide you with greater soil removal capability during the life of your CV system and will also increase the life span of your flooring by reducing debris wear.
HYBRID vacuum systems are directly comparable to any permanently filtered vacuum when used bagless. HYBRID units do encounter a static drop in airflow due to double filtering when used with a disposable bag but unlike bagless vacuums the permanent filter does not become dirty or clogged when using a disposable bag. A HYBRID vacuum system with a sealed disposable bag provides hygienic collection and maintenance and keeps your permanent filter clean. Using the HYBRID system without the disposable bag provides the easy dump-out emptying that many long time vacuum system users expect of their central cleaning system. HYBRID systems are quickly gaining in popularity with both consumers and installers as an efficient and easy way to give the homeowner a choice of tools in their cleaning arsenal.
Bagless Cyclonic Systems
Cyclonic Separation is a method of bagless filtration used in early central cleaning systems and is still used by a few manufacturers today. This design applies a spinning motion to the incoming dirty air combined with a conical shape inside the vacuum to force the heavier debris to the outside of the of the air stream where they drop into the collection bin below. A small amount of debris, usually 3% - 6% at peak efficiency and up to 10% or more at a low efficiency cannot be separated from the air stream and is pulled into a second filter. The secondary filter may be either a fiberglass media cartridge filter (a filtered cyclonic system) or a mesh metal screen (a fully cyclonic or "true cyclonic" system). Sometimes described as the most efficient method of central vacuum filtration the cyclonic separation vacuum system is perhaps the method of filtration we hear about most often from customers seeking to replace their old or broken central vacuum. It is also a design many new central vacuum shoppers ask about after seeing demonstrations at home & garden shows. Many times cyclonic vacuums are often erroneously referred to as "filterless".
The Good: Filtered Cyclonic Great Motor Protection, Excellent Peak System Performance, Venting Not Required.
Not So Good: Filtered Cyclonic Long Cycle Filter Lowers Performance, Cartridge Filter Retains Odors, Messy Maintenance & Bin Emptying, No Sealed Bag Option, Cost Of Filters (est. $20./yr), Limited Installation Locations.
The Good: Fully Cyclonic Excellent Peak System Performance, No Permanent Filter Odors.
Not So Good: Fully Cyclonic Higher Maintenance Requirements, Low Motor Protection, Messy Collection Bin Maintenance, No Sealed Bag Option, Exterior venting Required, Limited Installation Locations.
Read More About Filtered Cyclonic and Fully Cyclonic CVS
The Cyclonic system does not use a cloth filter and by design cannot use a disposable closed top collection system. The collection bin must be empty and ideally have smooth round sides to facilitate the spinning action that is required to separate the debris from the air. Some cyclonic vacuums use a fiber or paper cartridge filter -similar to that of a car's air filter- to remove the remaining debris before the air stream is pulled through the motor and exhausted out. This design is known as Filtered Cyclonic and is manufactured by Vacuflo, Hayden and others. The filter cartridge must be cleaned (Hayden) or replaced (Vacuflo) periodically. Another type of secondary filter for cyclonic separation is a metal mesh screen filter which is mounted inside the power unit just before the motor intake. Known as full-cyclonic or true-cyclonic, this system uses a permanent screen filter to stop large debris that is not separated by cyclonic action before airflow is processed through the motor. Fully cyclonic and filtered cyclonic use similar designs and operate on the same cyclonic principals only differing in their secondary method of filtration. Filtered cyclonic has a clean exhaust and does not require outside venting. Fully cyclonic systems are designed to vent debris (dust, lint, hair, etc..) outside and require an exterior vent.
Cyclonic Separation provides the least amount of resistance to airflow in the system when the filter system is clean. The cyclonic action is a proven low-tech approach to filtration that is used in many industries and filtration devices where bulk filtration is required. Interestingly cyclonic separation is often used in continuously operating very large (room sized) cleaning systems for industrial and manufacturing facilities where the exhaust is sent through a final filtering system before venting outside. Cyclonic separation is also used often in fluid filtration, particularly in the filtration of solids from lubrication fluids. Most fluid filtration systems use a backwash to clean the secondary filter for continuous operation. In residential central vacuum systems the cyclonic separation method has issues that limit its application for some users. Unlike large commercial systems or cyclonically separated fluid filtration the residential cyclonic central vacuum requires regular maintenance and cleaning to operate at acceptable performance levels. Filtered cyclonic models do benefit from increased airflow over permanent filter units. The trade for increased performance in filtered cyclonic models is additional maintenance and replacement of the filter media to maintain peak performance. Without peak performance the filtered cyclonic vacuums efficacy can spiral down at an exponential rate. Unable to use a hygienic closed-top disposable paper bag, filtered cyclonic vacuums can suffer the same maintenance issues associated with any bagless vacuum when it comes time to empty the collection bin.
Fully cyclonic central vacuums are sometimes marketed as "filterless" vacuums. The fully cyclonic system suffers from the same issues as filtered cyclonic models and often require more maintenance to sustain peak performance. The secondary screen filter in fully cyclonic models becomes clogged with light debris that will not be removed from the air including animal fur, carpet fibers, upholstery & clothing lint and other high surface area - low weight debris. This includes material such as polyfiber fill, feathers and Styrofoam. Unlike Permanently Filtered bagless vacuums where the filter element will automatically shed debris while you vacuum, Full Cyclonic vacuums must be manually cleaned when they clog. The filter screen will most often require maintenance each time the vacuum is emptied and in some applications, such as homes with multiple indoor pets of fur or feather, you will need to clean the filter screen more often to prevent low flow performance. Once debris begins to collect on the filter screen the vacuum system's performance will drop. A drop in airflow allows more (and smaller surface area) debris to escape the cyclonic action and become entrapped in the filter screen which in turn reduces the efficiency, allowing more (and smaller again surface area) debris to collect on the filter and so on, and so on. This downward spiral will quickly result in unusable performance and require maintenance often times before your collection bin is full.
A complaint we often hear about cyclonic vacuums is messy maintenance. The secondary filter is mounted deep inside the vacuum and maintenance results in dirt and debris falling out of the vacuum onto the wall, floor and the person's clothing that is performing the required maintenance.
The messy maintenance of Cyclonic vacuums is often a sore point for unsuspecting new CVS owners. Cleaning the central vacuum quickly becomes a job for the "man of the house" in homes with a cyclonic central vacuum. The routine maintenance of a cyclonic vacuum may also lead to dirt sent back into the air where fine particulate may float around for hours becoming a hazard to those with allergies or asthma. One customer who described himself as allergic to house dust told us of his "cyclonic vacuum maintenance regimen" which involved a painters dust mask and a tire/wheel brush with a long handle to clean the filter screen inside his fully cyclonic power unit. The inability to use a closed-top disposable bag limits the cyclonic vacuum mounting locations to dirty areas including the garage or unfinished basement.
Another design concern of Cyclonic central vacuums is the requirement for an outside exhaust. Due to the volume and size of particles that are vented from these vacuums they must have their dirty air exhausted to the outside air to prevent contamination at the mounting location.
Fully cyclonic vacuum systems are not dangerous due to venting requirements, just more limited for some applications and locations. Permanently filtered, Hybrid and Disposable Filter vacuums can be vented within the same room which they are mounted, though we recommend venting any central vacuum to the outside when possible.
Cyclonic vacuums are limited in the type of debris they can safely or easily recover and should never be used to clean ultra fine particulate including baby powder, dry wall dust or fireplace ashes. Cyclonic action in residential central vacuums is not strong enough to remove these low weight, high surface area particles from the air stream and they will be pulled through the motors impellers and exhausted out of the vacuum. We are often asked about the potential for motor damage if a fully cyclonic vacuum is accidentally overfilled resulting in large debris being pulled through the motor. While a filtered cyclonic system protects the motor from the possibility of overfill damage a fully cyclonic vacuum does not.
This type of damage can destroy a central vacuums motor impellers which are not designed to contact debris and can destroy the entire motor unit if contact is severe enough. Accidental overfill damage is not considered a manufactures defect and is not covered by the warranty. No central vacuum motor system is designed or specially made to contact debris. Fully Cyclonic vacuums over time will also develop a collection of dust on the impeller blades. In humid areas this can happen more quickly which can result in an out-of-balance condition that can lead to motor bearing failure. For those fully cyclonic vacuum manufacturers that offer a lifetime parts warranty this type of damage would be covered as it is not the fault of the user. Careful consideration should be used with the application of a fully cyclonic central vacuum in a home where the cleaning system may be used by a cleaning service employee, children or other persons who may not keep a close eye on the debris level in the collection bin.
Bag Only Systems
Disposable filter systems use a single disposable bag for both filtration and collection, what is often referred to as a "Bag Only" power unit. The Bag Only system uses a closed top filter fitted onto the intake tube to force all vacuumed debris into the filtration media. While all other functions and features are similar to any other central vacuum filtration method the Bag Only system is more similar to the maintenance of a paper bag portable vacuum. When the Bag Only is full the entire filter and collection system is disposed of in one step. Bag Only systems offer hygienic
filtration and collection where the user, the vacuum and the surrounding areas are not contaminated with dust during a normal bag change. With the ability to dispose of both filter and collection system you also rid your vacuum of more odors each time you change the bag, important for those homes with inside pets or where the vacuum power unit may need to be located inside one of the clean rooms of your home. Bag Only systems are one of the preferred filtration method for those who are sensitive to dust, suffer from allergies or have breathing issues including asthma that may be triggered by small particulates in the air.
The Good. Excellent Performance Short Cycle Filter, Great Motor Protection, Easy & Hygienic to Maintain and Use, Great for Any Installation Location, Great Design For Users w/Allergies or Asthma.
Not So Good. Extra Cost Of Disposable Bags approx $15-$20/YR., No Secondary Motor Protection, Limited Models Available.
Though it is among the most sanitary filtration systems used in modern central vacuums the Bag Only (disposable filter/collection) system is available in fewer models than other methods with only a limited selection available. Bag Only systems use only one filter, the disposable container that may be traditional micro filter paper bags or high efficiency synthetic bags.
Most Bag Only systems also contain a non-filtering bag support made from fiber mesh, open cell foam or a simple metal bracket that supports the bag and allows airflow around the filter media. Unlike Permanent filter, HYBRID and Cyclonic filter systems the Bag Only system does not provide any additional or secondary motor protection should the vacuum be run without a bag in place or should the bag not be installed properly during bag replacement. Bag Only units require no maintenance or cleaning other than bag replacement. Bag Only vacuum system users also benefit from a short cycle of the filter system, which restores the vacuums airflow and cleaning performance to 100% each time the collection system is replaced. This assures during the vacuums life span each area being cleaned will receive peak performance, which will remove embedded debris resulting in less floor covering wear. More frequent peak efficiency available in Bag Only systems also results in higher usage efficiency. The simplified hygienic maintenance of a Bag Only system means you will spend less time cleaning your home and less time cleaning your vacuum with a Bag Only type vacuum system.
Bag Only units require the consumable disposable containers that can cost $15 - $20 per year. Bag Only units can be vented to the outside or vented at the unit providing for unlimit