Don't know how your system is set up but most I am familure with by pass for 2 reasons High temp and pressure regulation.
pressure regulation bypass can go right back into the incoming draw line if you like, less plumbing or run it back to your fresh tank. Only way I see it being a problem is if your hooked up to a water supply, your F tank is full and your machine is running , you could over flow your tank.
High heat, Mine never gets that hot!!!