I am new in to the business and am in the process of researching equipment. Money is not too much of an issue, so I want to buy a machine that can handle about anything I will throw at it. I am going to be doing graffiti removal, house washing, new construction brick cleaning, decks, flat work, and house washing. I am looking at 2 hot water machines to mount on a trailer. One is a 3500 PSI / 5.6 GPM unit and the other is a 4000 PSI / 4.0 GPM unit. Which one should I get?
Supply not being a factor, more gpm is better. Will you have a water tank? If yes, then the 5.6, If not, I would go for the 4.0. The reason being that many times you won't be able to get more than 4 or 5 gpm from a spigot, so without a tank, you will have problems. 4 gpm should be plenty, unless you will be doing a lot of flatwork. More gpm speeds the rinsing factor.


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Definitely I would go with the 5+ GPM @ 3500 PSI
unit. I question the 5.6 GPM specification though. :confused:
in most scenarios volume beats pressure.

General Pump rates the TS2021 at 5.6 GPM at 3500 PSI,
I have never seen that pump perform at 5.6 GPM, I am
partial to the AR XW2128 which is rated at 5.5 GPM @ 4000
PSI and will perform at this specification.

Here is a picture of one of our Hot Sellers a 5.5 GPM 3500
PSI trailer package powered by a 20 HP Honda.

Or if you really want a power house we have an 8 GPM @ 3500 unit also:



John is so very right in saying that you might have trouble getting the volume of water you need at a faucet. My unit is rated at 4.6 gpm and I can suck some faucets off the wall. So I "now", always put water in my tank and do not rely on my float tank.

There are units out there rated at 4-5 even 6000 PSI. Regardless of volume, get one and I hope your a big guy in good shape! I use my unit at 3000psi and after a full day of work my hand and shoulder is wore out. I have a friend who uses a general pump rated at 5000 psi and uses it around 3000. He cranked it up for me to check out the pressure one day and I can tell you no one I know wants to use it all day! BUT

Something else to consider, a unit rated at 3000 psi used at max pressure all the time will wear out faster than say a 4000 psi rated machine used at 3000. Think about it. Most cars can run over a 100 MPH but try doing it all the time, somethings gonna give!

Just my opinion.
Right, but when you crank down the PSI (via down throttle or unloader) aren't you also bringing down the GPM?? I was told that you should only decrease PSI by changing nozzles. Thoughts?
Kev, as I understand it from my equipment "guy" most unloaders shouldn't be tampered with, but idling down is you best option here if you don't have a dual lance wand.



Moderator / Sponsor
A dual lance / aka: variable pressure lance or
changing nozzles would be best.

I have heard some debate on pros
and cons of running an air cooled angine
at reduced throttle for prolonged periods.

I believe there was some discussion on
this BBS on that subject a year or 2 ago.

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