Few features to look for when choosing a portable extractor:
PSI - There are extractors that go from 50 psi - 1200 psi. If you plan to do
mostly residential homes and upholstery having a machine that does is between
50-250 psi is usually sufficient. Too much pressure and you'll get the common
compliant that you're leaving the carpet to wet buy homeowners. When cleaning
upholstery typically you'll only be at 50 psi and for most residential carpets
you'll be either at 100 or 200 psi. If you plan on doing a lot of tile and grout
you'll want high pressure of 1200.
Heat vs. No Heat - Hot water does assist in the cleaning process. It will
help in breaking down the oil and debris in the carpet. Soil in the fibers
typically will extract easily with no heat, though the oil in the fibers of a
carpet are more easily extracted with heat. Heat will speed up the process,
though with no heat agitating the carpet before will assist or a higher PSI will
also assist in extracting without heat. The labor cost if running crews is much
lower using heat than using only a cold extractor. Another option is pouring hot
water in the extractor and pre-spraying before hand. The downside to heat is
you'll be using more electricity and risk tripping the breaker with some
Tank Size - The bigger the tank the less stopping to refill when cleaning.
If you're going to be doing a lot of automobiles and upholstery a 3-6 gallon
should be ok, though if you're doing a lot of rooms you'll want a larger tank.
Weight & Size - Remember you'll need to load the machine in a truck or
van. Some machines are terribly heavy, while others aren't.
CFM (Cubic Feet per Minute) - This is the air flow which will assist in the
drying time for the carpets
H20 Lift - This is how much the lift is for pulling back up the water that's
been released into the carpet. The more you lift the dryer you'll leave the
carpet. A good balance between lift and CFM tends to be better.
Look for attachments you'll need. Most portable carpet extractors aren't
sold as packages so you'll want to make sure to purchase the vacuum &
solution hose, wands, upholstery tool and crevice if needed. Packages are put
together occasionally so make sure to check.