As you know I am a big fan of using backpacks for some types residential housework, I find they are very versatile and sometimes preferential to using the hose reel.  I fit mine to a trolley/sack barrow and away you go.

Backpacks can also be used for small soft wash jobs.  Soft washing is the process of cleaning external hard surfaces and removing organic growth such as algae by applying cleaning solutions.  It is an alternative to jet washing which can use a lot of water and always gets my lovely clean windows dirty!  If you are looking to add soft washing to your service, a backpack with a water fed pole and  suitable spray nozzle DA Applicator with Full Cone Nozzles for Softwash application ( can be a good way to get you started.  They are also handy for business offering  garden maintenance as a service.

Most backpacks come with a standard 12-volt water pump.  This however is not designed to be used with the type of cleaning solutions used for soft washing.  I always say if you flush the pump through with clean water after each use you might get a year out of the backpack and that is not too bad.  You can however extend the life of the backpack by replacing the pump with a chemical pump 12 Volt Replacement Chemical Pump for Backpacks (

It is straightforward to do.

  • Make sure the back pack is empty and remove the fuse.
  • Take the plastic plate off the bottom of the backpack, there is usually about 8 screws holding it on.
  • Loosen the jubilee clips so you can slide the inlet and outlet hoses off the pump. If your back pack is fairly new these will be in good condition, if they are rusty, I would replace with new.
  • There are usually 4 screws holding the little rubber feet of the pump on, unscrew these.
  • Gently remove the pump and you will see two cables on the pump normally red and black (positive and negative), cut these as close to the pump as possible to leave yourself plenty of cable to join the new pump.
  • Get your new chemical backpack pack pump, mount it in position and use the same screws to secure it in place.
  • Attach inlet and outlet hoses with the jubilee clips. Top tip, some WD40 sprayed on the thread of the jubilee clips makes it easier to tighten them up.
  • Connect the wires using wire connectors, for this I find the best ones are Scotchlock connectors and we include 2 with our backpack pumps (one for the positive cable and one for the negative cable). Slide the red wire from the pump and the red wire from the backpack into each end of the connector.  Using pliers push the silver tab down the make the connection, then close the small plastic cover which clips into place.  Repeat for the other cable.
  • Check the fuse and replace if needed, put the fuse back in the fuse holder.
  • Stand the backpack up, pour a jug of water into the backpack, switch it on, you will hear the pump kick in, if the outlet is not open the pump will stop automatically. Make sure you do not have any leaks.
  • If there are no leaks, switch the backpack off, lay it down, replace the bottom plastic cover and that is job done.

We also have a short video demo Installing a chemical backpack pump