Dishwasher fills tub continuously

Dishwasher fills tub continuously until float turns it off whether in cyle, during drying or after cyle complete. That means during drying when the dishwasher is trying to dry the dishes the tub fills up preventing drying. This is a new dishwasher that I've never used. I allways noticed the tub was full of water, but thought that was just to keep the seals moist so they don't rot. I've been in my house 5 years and only hand washed my dishes because it was more convienient. Now that there are more people in my life I want to use it. Is there something wrong with the curcuit board? It's like the fill switch works separately or own its on accord, is this right?