I have K7 and works great on my 5.5 gpm, 2500psi. Won’t work on my 4 gpm 4,000psi. K7 is only good up to 3,500 psi. I had a giant on a 4 gpm, 3500 psi and worked exactly the same and never failed. Still have it on a 5 year old back up machine.
Power Wash Store sold it to me with my machine and never told me it wouldn’t work. I called them to troubleshoot shoot it and they still didn’t know why it wouldn’t work. They insinuated it was my installation not the K7 and stopped calling me back . I no longer purchase from them.
Just bought my machine and again was told that flow unloaders are practically useless because they are so finicky. I just said whatever I’ll put one on later, my start cash was running low anyways so maybe down the road. I will miss being able to knock down wasp nests from gable end peaks tho. How do you guys get those down? Break out the big lance?