Hi, I have a 21,000 Gal, Marcite/Granite Pool. I am a new pool owner and am still trying to become familiar with the ins and outs of pool care. We left on vacation for 2 weeks and had someone care for our pool, but on our return when I try to turn the pump on, it runs dry. I have refilled it with water and usually hitting the reset button works, but not this time. I also tried letting air out by the air release valve on our Triton Sand Pump and when water starts to run I close the valve and start it again. I did this three times, each time I let the air out, it took about 5 - 10 min. for water to start running through the valve. Could it be possible that I did not let all the air out and should have let it run through longer? Any help is appreciated. Have a great day!