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What type of pump is used by this product?

  1. Apr 16, 2009 #1
    Dear Engineering Experts,

    I saw this pressure washer on youtube :

    and could not figure out exactly what type of pump is used. I could not find the manufacturer's home page. Websites featuring this are :

    http://home-solutions.hsn.com/nomad-h2o-on-the-go-power-washer_p-3652885_xp.aspx [Broken]

    http://www.comforthouse.com/pressurewasher.html [Broken]

    I know that there are several types of pump that can product pressurised water for example, water pressure booster pump. So, it could be a piston pump, diaphragm pump or a centrifugal pump.

    It is running on DC current and the pressure it produces seems to be around 80psi and the flow rate is very low.

    more info can be found here:

    Hope to get some advise from forummers.

    Have a great day
    Best regards
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Apr 20, 2009 #2
    I don't think it is a piston pump or a diaphragm pump because both of the produce a pulse type spray. It could be a centrifugal pump or it could be a small air compressor used to pressurize the tank and force the water out.
  4. Apr 21, 2009 #3
    Uh...No. You can't achieve the pressures needed for a power washing with a centrifugal pump, it has to be positive displacement. And compressing the air inside the tank would be very inefficient. The device most likely uses a gear pump or vein type pump.

  5. Apr 21, 2009 #4


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    They are generally plunger pumps, at least on the larger gasoline powered models ( I'm guessing that the small electric ones are as well) - you get a lot of pressure at low flow rates very simply with a plunger pump. Picture it as a car engine but with the crackshaft driven and the pistons pumping water.

  6. Apr 22, 2009 #5


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    That depends on what type of pressure you have determined you need for 'pressure washing'. What are we washing? How easily is the residue removed? Those sorts of questions. A typical pressure washer will create pressures of several thousand PSI at several gallons per minute. But, as it so happens I 'pressure washed' some parts today rinsing out some residue with a 5.5 HP gas motor and a centrifugal pump. I have repaired a pressure washer pump that spec'd at 3000 PSI 5.1 gallons/minute which used ceramic pistons. The piston is actually a ceramic sleeve with a bolt down through the top that screws into a connecting rod assembly. The piston slides in and out of a chamber with check valves for input and output. A crankshaft with connecting rod assembly runs in a seperate chamber so any leakage from the pump drains out instead of leaking into the crankcase. Anyone reasonably mechanical can repair these pumps.
    Centrifugal pumps can achieve 100 PSI without to much trouble. Enough for washing some things.
    I watched the video and I'd say there is no more than 100 PSI there. It takes a 5 HP electric motor to run a 2000-3000 PSI pump at 5 gallons/minute. I would be willing to bet that it is a centrifugal pump. For the money they are asking for this washer I don't think a positive displacement pump plus the unloader valve could be fit into the budget. You cannot dead-head a positive displacement pump where a centrifugal pump will just sit and run in this condition.
    Last edited: Apr 22, 2009
  7. Apr 23, 2009 #6


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  8. Apr 23, 2009 #7


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    Not sure who your post is directed to Fred, but that was my whole point. Most pressure washers are in fact in the several thousand PSI range. But that is not to say you cannot wash some things with less pressure. So if it squirts out of a nozzle, and is able to wash debris off, it is technically a pressure washer. I'd say the one in question is advertized that way since it doesn't look to me like several thousand PSI at the nozzle.
  9. Apr 25, 2009 #8


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    Looking at the product and seeing how it has an on-board tank of water, my guess is the unit pressurizes the tank with air like a super soaker.
  10. Mar 29, 2010 #9
    you can look at product pictures at http://www.ingersollrandproducts.com/IS/Category.aspx-am_en-24753" [Broken] they have all different types so you can see what kind yours is
    Last edited by a moderator: May 4, 2017
  11. Mar 31, 2010 #10
    I have seen hose nozzles that connect to the garden hose be called pressure washers, too

    its hard to beat a 1/4 drive socket with a 1/8-3/16th hole clamped into a chunk of broke garden hose for a nozzle, though

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