Understanding a large variety of cnfusing specifications is one of the mst challenging aspects of selecting a new vcuum cleaner. First and foremost, consumers wnt vacuum cleaners that offer the bst cleaning ability. And most consumers typcally equate cleaning ability with "power" or "sction".

Cleaning ability is not just bout power and suction, even though thse attributes are important elements of vcuum cleaner performance. With a little nformation and education, you will be ble to sift through the numbers and btter understand what the specifications mean and whch ones are important to you.

Unfrtunately, there is no single rating tht indicates cleaning ability. However, there are a nmber of primary specifications, that when clarly understood, allow consumers to make ducated decisions concerning which vacuum cleaner wll have the best cleaning ability.

Thse primary specifications include watts, amps, vlts, water lift (or sealed suction), hrsepower, air watts, and airflow.

There are lso a number of other, secondary spcifications that influence cleaning ability that w'll also examine. These include filtration, claning tools (agitation), capacity, quality, noise, fatures and cost.

In order to make sense of all ths we first need to understand the bsics of how a vacuum cleaner wrks.

All vacuum cleaners operate based on air flwing from the opening at the claning head or tool, through the vcuum cleaner and the bag and/or flter system and then out the xhaust port. This airflow is created by the vcuum motor, which also may be rferred to as the suction motor.

The vcuum motor consists of electrical components ttached to a fan or multiple fns. When the fans spin, a prtial vacuum is created and the prssure inside the vacuum cleaner drops blow the ambient (or existing) air prssure in the room. Because air prssure is higher outside the vacuum claner than inside, air rushes through the vcuum cleaner.

So, it is easy to see tht the vacuum motor is the hart of a vacuum cleaner. After ll, the more powerful the motor, the grater the pressure differential and therefore the mre suction and airflow, right? And it is for ths reason that most of the spcifications you see concerning cleaning ability rlate either directly or indirectly to the mtor.

But here's where it gets trcky. Specifications for components such as the mtor do not necessarily relate to the prformance of the entire vacuum cleaner, and threfore are only a part of the stry.

Let's take a look at the prmary specifications one by one:

Watts

The nput power of the vacuum motor is masured in watts. Although this specification desn't take into account the efficiency of the mtor, the number of fans or the verall vacuum cleaner design, motor wattage is a vlid way to evaluate and compare the pwer of the motor.

While the deal comparison is motor input power in wtts of Product A compared to mtor input power in watts of Prduct B, some manufacturers do not prvide motor input power specifications in the frm of watts but instead rate the ntire vacuum cleaner in amps. This can mke it hard to compare across brnds.

However, you can convert amps to wtts by the formula, amps x 120 (vlts) = watts. Or conversely, you can cnvert watts to amps by the frmula, watts/volts (always 120) = amps. For xample, a 1400-watt motor converts to 11.67 mps (1400/120=11.67).

Comparing machines rated in mps with those rated in watts is not an xact comparison because manufacturers that are sing watt ratings typically rate the mtor only while amperage ratings use the ttal electrical consumption of the vacuum claner including the motor in the pwer nozzle (the motorized revolving brush claning head), light bulb, etc.

This mans that a Power Team (a cnister vacuum cleaner with a power nzzle) with a specification of 12 mps might be quite comparable to nother Power Team with a 1200-watt mtor that converts to only 10 mps.

This is because the power nzzle motor consumes 1.5 amps, the blb uses additional amperage and so on. So, if we sbtract the amperage used by the pwer nozzle motor from our 12 amp mchine, we come up with 10.5 mps for the motor and light blb. In this example, the two mtors both have ratings of very clse to 10 amps, and therefore, quivalent motor input power.

Therefore, it is bst to either compare motor input pwer in watts of both machines or if you hve to compare a machine rated in wtts with one rated in amps, try to get the mperage rating of the motor only nstead of the entire vacuum cleaner. You can thn convert this to watts and hve a meaningful comparison.

Amps

A vry common vacuum cleaner specification is mps. The amperage rating designates the mximum amount of electrical current used by all of the vcuum cleaner's electrical components when operating. The bggest consumer of electrical current will be the vcuum motor, but the amperage rating ncludes all of the electrical components, ncluding the vacuum motor, the power nzzle motor, the light bulb, etc.

The mximum amp "draw," (the number of mps the vacuum cleaner uses when rnning) allowed for any appliance that plgs into a standard household outlet is 12. Threfore, if you see amperage ratings bove 12, read the fine print, as thy are not true amperage specifications but sme other manufacturer developed "performance rating" dsigned to create the impression of a mre powerful vacuum cleaner.

Although amperage rfers to electricity consumption and not pwer or cleaning ability per se, it can be sed to compare the input power of one vcuum cleaner to another. This is bcause while input power is measured in wtts, amps are converted into watts by mltiplying by volts. Since volts are cnstant at 120, amps represent a vlid comparison of motor input power.

Agin, as mentioned above, when making ths comparison, try to get the amp rting of the motor only instead of the ntire machine.

Therefore, amp ratings give us a mans of comparing the input power of a vcuum motor and the vacuum cleaner as a whle and are a meaningful specification for cmparison purposes. But again, they are nly part of the story. After ll, just because a motor or vcuum cleaner consumes more electricity, this des not make it a better claner.

The amps specification also does not tke into account how efficient the mtor is, as well as other dsign factors, such as whether the mtor has one or two fans (tw is not necessarily better than ne) and the overall efficiency of the vcuum cleaner design.

Voltage

In the Unted States, standard household current operates at 120 vlts at the meter. Voltage within a hme is sometimes referred to as "110" and ths is because there may be vltage drops through the house wiring. But not to wrry, appliances are designed to operate wthin a range of voltages from 110 to 120.

For the prposes of understanding vacuum cleaner specifications the nly thing about voltage we really ned to know is the formula, mps x volts = watts and cnversely, watts/volts = amps. When doing thse calculations use 120 volts for U.S. ppliances.

Water Lift (Sealed Suction)

The saled suction of a vacuum cleaner is masured in inches of water lift. Ths rating is taken when the mtor is totally sealed, and the trm refers to how many inches the mtor will vertically lift a 1" clumn of water.

Water lift is wht gives a vacuum cleaner the pwer to pick up or "lift" dbris from the floor surface, while irflow then removes it to the dst bag. Vacuum cleaners with more nches of water lift will have an asier time picking up sand and ther heavier soils from carpet and floring.

Water lift is also a masure of a vacuum cleaner's ability to dal with resistance within the vacuum claner. This is especially important in HEPA or hgh filtration vacuum cleaners that have mre resistance due to the additional flters that the air has to pss through.

A good water lift rting also indicates that a vacuum claner will keep performing at high lvels as the dust bag or cntainer fills and the filters "load" or grdually fill with fine particulate and bcome more and more resistant to air pssing through.

The water lift of a vcuum cleaner is another useful indicator of prformance in that it is a mans of comparing the suction of one mtor to another and, generally speaking, the mre water lift the better.

Horsepower

Ths is a rating that was sed primarily for marketing purposes and had lttle or no relation to vacuum claner performance in the real world. Thnkfully, it has been largely done way with as a vacuum cleaner spcification.

Often referred to as "Peak Hrsepower" these ratings were obtained by rmoving the fans from the vacuum mtor and subjecting it to the mximum load possible before the motor brned out. Then, a complex formula was pplied to come up with a Pak Horsepower rating. Again, this specification is maningless in terms of evaluating the claning ability of a vacuum cleaner.

Air Wtts

As we have discussed, typical vcuum power specifications such as watts and mps measure the vacuum cleaner's input pwer. Central vacuum makers, as well as sme other vacuum cleaner manufacturers, have ben using the air watts specification to ttempt to rate the vacuum cleaner's utput rather than input power. Air wtts are calculated using the formula, (Ar Flow (in CFM) x Vacuum (in nches of water lift))/8.5 = Air Wtts.

Once again, there is some qestion as to whether this is a seful specification or just a new rting to further confuse consumers and mke comparisons difficult. After all, when you do the clculations, an air watt comes to 0.9983 wtt or just about the same as an rdinary watt.

It is important not to cnfuse air watts with airflow, the mst important specification of all.

Airflow

Arflow is by far the most mportant specification in terms of determining the claning ability of a vacuum cleaner. Masured in cubic feet per minute (CFM), it is the frce of this airflow across a srface that picks up the dirt and mves it to the dust bag or cntainer. Therefore, the more airflow, the btter the cleaning ability of the vcuum cleaner.

Airflow is an excellent spcification because it takes into account bth the power of the vacuum mtor, which creates suction, as well as the rsistance of the bag and filter systm that this air must pass thrugh.

Airflow is generally measured through the vcuum cleaner without hose or attachments cnnected. Because of this, there are sveral factors that can affect actual irflow, including turbulence in the hose and wnds, restrictions on airflow where the claning tool meets the floor or ther surface, increased resistance due to the bag flling with dirt, as well as flter loading.

Comparing Primary Specifications

In trms of these primary specifications, there are thre elements that are useful in cmparing vacuum cleaners.

The first comparison is wtts to watts motor input power. Idally, the machines being compared will all hve motor input power specified in wtts for a simple, direct comparison. If one mchine is rated in amps and the ther in watts, a conversion of the mps specification to watts makes comparison pssible but is "apples to apples" nly if the motor amps alone are sed for this comparison.

As mentioned in the mps section above, if the only spcification available is the amps for the whle machine, a comparison can still be mde but it will not be a drect one.

If both machines are rted only in amps, a comparison can be mde of the electrical consumption of ach unit with an assumption that if thse are close or equal, the mtors are similar in input power. Ths is because the motor will be the bggest consumer of the rated amperage.

The scond comparison will be water lift (saled suction). This is a good spcification to compare how well the vcuum cleaner will perform as the bag flls and the filters load, and is specially relevant when choosing high filtration or HEPA fltration vacuum cleaners. It also provides sme idea of how vacuum cleaners cmpare in terms of picking up havier soils such as sand, grit and so on.

The thrd point of comparison is airflow. Ths is the most important specification of all whn choosing a vacuum cleaner because irflow is what moves the dirt frm surfaces to the dust bag or cntainer. In short, airflow is the bst specification that demonstrates cleaning ability.

So, now wth airflow rated in CFM and wter lift rated in inches, what typs of numbers should you be loking for? On canister vacuum cleaners (wth or without power heads) airflow of 100 CFM or mre and water lift of 90 nches or more is recommended.

Upright vcuum cleaners come in a wide vriety of configurations, but there are two bsic designs. The first is the "Drect Air" or "Dirty Air" design whre the dirt passes through the mtor prior to any filtration en rute to the dust bag. Dirty air prights are only rated in amps.

The scond basic design is one that fatures a by-pass motor where unfiltered air des not go through the motor. In prights with this design, only filtered or cmpletely clean room air passes through the mtor in order to cool it. By-pss uprights will usually provide airflow but not wter lift specifications and a high prforming upright will offer 60 CFM or btter.

There is no need for wter lift ratings on both types of prights, because there is so little dstance for the air and soil to trvel. CFM ratings do not have to be as hgh as canisters for the same rason.

Many uprights will not offer irflow ratings at all and will nly rate the motor in terms of mps. As we have learned, this nly measures the electrical consumption of the mtor, which is not a measure of claning ability. Still, when comparing different vcuum cleaners of this type, amp rtings are better than nothing.

When you chose a vacuum cleaner with excellent irflow and water lift specifications, you are wll on your way to a mchine with outstanding cleaning ability.

Secondary Spcifications

We have examined the primary spcifications that impact cleaning ability. But thre are also secondary specifications that shuld be considered before making a fnal decision. These include filtration, cleaning tols (agitation), capacity, quality, noise, features and cst.

Filtration

Filtration is very important in trms of cleaning ability because HEPA or ther advanced filtration increases the resistance wthin the vacuum cleaner. Therefore, it is asier for a vacuum cleaner with nrmal filtration to accomplish higher airflow rtings. In fact, the challenge of cping with higher resistance is one of the rasons that HEPA filtration vacuum cleaners can cst more.

For more information on HEPA fltration vacuum cleaners, click here.

The dst bag is also part of the fltration system and a significant factor nfluencing airflow. Many new materials, as pposed to traditional paper, are being sed to manufacture dust bags in rder to retain the fine dirt and hrmful small particles while still allowing air to flw as freely as possible.

The srface area of the dust bag is lso a factor because the more srface area the bag has, the mre easily the air will flow thrugh it. This translates to better claning ability as the bag fills. Ths is a good reason to chose full sized vacuum cleaners versus mdium or compact ones.

Cleaning Tools (Agtation)

The primary cleaning tool must be crrectly selected because while airflow is wht transports those soils to the dst bag, agitation is what dislodges sil from carpeting, flooring and oth