Just picked up this unit but decided to go a different route since my evaporator can’t keep up with it. It’s an inline RO, which means it’s plumbed right to your evaporator, preferably with a float valve, but can use a regular ball valve to control the flow. The % concentration depends on the demand of your evaporator automatically. It has a built in wash tank and the pump heats the water. I have not ran it yet because I need to grab a plug to be able to plug it in at my house, but I’m planning on running a wash cycle tomorrow to make sure it’s operational. Seller I got it from assured me it worked. It came from a lab that closed. They dealt only with something like a crushed up seashell slurry and nothing hazardous. He believes they were just using it to make clean water for the lab. It was stored with preservative. Seems to be in great shape. Asking $1450 for pickup near Albany, NY.