So I have a question I have been getting mixed answers on for a few years now. The question stems from my system turning on my cleaner booster pump during freeze protect even though it is not in the freeze protect program to turn on. I have been told it is default for the booster pump to turn on since there is water in it and it needs to be moving to prevent freeze. But I have also been told that water is being pushed through the booster pump from the main pump even when the booster pump is not running. My concern is I don't want to leave my polaris pressure cleaner attached in the pool all winter but if the booster pump runs without the pressure cleaner attached it sounds awful (almost like gravel is flowing through it, a grinding sound). I've been told it's fine and won't damage it but I have a hard time believing that. It's so loud that it will wake me in the middle of the night if it is activated from freeze protect. I was basically told just to leave the cleaner attached if I was worried about it. However, I don't want my cleaner running for a day or days at a time if at cold temps. That's when parts on it start breaking.
So my question is basically 2 parts:
1) Is my cleaner booster pump really ok to run without the cleaner attached even though it sounds terrible?
2) Is there something I can attach to the return fitting in the pool to reduce flow and create the pressure needed for the pump to run in place of leaving the cleaner attached?