We just renovated our pump room with three brand new Triton Fiberglass sand filter and a brand new 7 hp pump. We backwashed the other day to test something out and after we put the valves back in place to filter we have no pressure to the filters. We opened the pump and filled it and the lines with water and fired it up and still nothing? I am looking for how to get the filters filtering again because we open in a week. any help would be much appreciated, thanks.