My waterfall will not go. I turn the knob and hear bubbling but nothing happens. I also have a fountain which is not working (not even a bubble). The return lines are not putting any water out. I have a spillway from the spa into the pool and it is going full force, unlike I have ever seen. I have no clue what to do. My cleaner is working and running around the pool with no problem. My filter is working, no problem. What should I do? Could my pipes have frozen? TIA!!