boss 14 Report post Posted May 21, 2009 I have a machine that is 8gpm 3000 psi. I was wondering if increasing the pressure through the unloader would decrease my gallons per minute. Also would it cause any harm. I am trying to get more pressure with a less gallons per minute because a lot of water sources will not keep up. Share this post Link to post Share on other sites
One Tough Pressure 580 Report post Posted May 21, 2009 You will not get more pressure than the rated 3000 psi. You can reduce gpm and maintain the 3000 psi though. This would be done through the use of a steam valve to bypass water on the high pressure side. Do you have a hot water machine that may be equipped with that valve already? Share this post Link to post Share on other sites
boss 14 Report post Posted May 21, 2009 It is a cold water machine. Not familiar with a stream valve what is it and where? Share this post Link to post Share on other sites
814jeffw 71 Report post Posted May 21, 2009 Just wondering if you have a buffer tank and how big it is? Jeff Share this post Link to post Share on other sites
Beth n Rod 1,279 Report post Posted May 21, 2009 I have a machine that is 8gpm 3000 psi. I was wondering if increasing the pressure through the unloader would decrease my gallons per minute. Also would it cause any harm. I am trying to get more pressure with a less gallons per minute because a lot of water sources will not keep up. Boss, Welcome to TGS. Please go to your My Controls and add your signature. Thank you. Beth Share this post Link to post Share on other sites
plainpainter 217 Report post Posted May 21, 2009 Just put some real small tips in - it will maintain the high pressure yet decrease the volume. Share this post Link to post Share on other sites
PressurePros 249 Report post Posted May 21, 2009 It may be unwise to decrease production rates of a high volume machine. The simplest solution is to get a reserve tank. 100 gallons should serve you fine on resi work. There are many available footprints to fit your vehicle if space is an issue. Share this post Link to post Share on other sites
Paul Kassander 26 Report post Posted May 21, 2009 If your unit is set up with a trapped pressure unloader you can reduce the output at the gun by simply installing a smaller nozzle, any excess water that is unable to be pushed through the nozzle will be sent into bypass. As an example if your unit is 3000 psi @ 8gpm you would use a 9 nozzle. To run 6.5 gpm= #7.5 nozzle, 5.2 gpm= #6. If you want to reduce pressure and flow you will need to adjust your unloader to the max pressure you want to achieve and then size your nozzle accordingly. If you do have a large volume machine it is best to have some sort of a buffer tank though, you do not want to starve the pump. Share this post Link to post Share on other sites
