I would clean it out before storing. I would also run clean water through it to get rid of chemicals. Have nothing but trouble with mine (pressure problems if you don’t clean out) and it finally died today. I used it a few weeks ago, left a tiny bit of moss killer in it and threw in garage. Took out today to continue what I was doing. Didn’t work. Opened unit up, the diaphragm pump motor was completely rusted.
To date, I have used it about 100 times and not had any issues at all. Depending how tight you adjust the fitting on the head, it can spray from a few feet to a few yards. It has been a quality tools from me.
