We followed all instructions to fill and start our brand new hot tub. It ran for 20 hours. Got up to proper temperature and then shut itself off. Two hours later we went to use spa and pump is making wretched noise and not circulating any water. Contacted customer service and they sent air lock release instructions via email. Just tried them. No go. Very disappointed. I want my brand new spa to work. I don't want to have to empty it and refill and reheat. I don't know what next step is yet but I think next time I would purchase from local dealer who will come out and take a look when things go a wry.