Just bought a used 2020 GD 310 GK and started to operate the water system in my driveway before we head out camping. I first sanitized the FW tank. I pumped the solution into the FW tank then filled the tank. This is where I think I screwed up. I probably should have filled the tank first with the Nautilus in the "Power Fill Tank" settings till almost full then pumped the chlorine solution. When I filled the tank with city water I had the Nautilus valves in the "Sanitized" position. It took longer than I thought it should and now after I found plumbing diagrams on this site i realized that I pushed 80 gal of water through the pump while it was turned off. When I started the pump in the "Dry Camping" valve positions to clear the lines of antifreeze and push the chlorine solution through all the fixtures I found that the pump runs continuously and there is air in the line that won't purge....did I damage the pump by filling the fresh water tank in the "Sanitize" valve position? I have read many posts on this site and have confirmed there are no air leaks in the lines and have also installed a shut off valve on the inlet of the city water connection in case the check valve was defective. Any help would be appreciated. Thanks