Other TeeChart implementations have a method to set the automaticMinimum / automaticMaximum for axis objects independently.

In TeeChart HTML5/Javascript, as a workaround, you can override checkMinMax function to have a fixed minimum=0, keeping the maximum automatic. Ie:

  Chart1.axes.left.checkMinMax=function() {
    var s=this.chart.series, h=this.horizontal;

    if (this.automatic) {
      this.minimum=0;
      this.maximum= h ? s.maxXValue(this) : s.maxYValue(this);
    }
  }

But automaticMin and automaticMax properties would be helpful.