2 year unit blow heat for about 2 minutes then...

Question

The weather king gas furnace is only 2 years old and has been nothing but one problem after another. In the 2 winters that I have owned the unit it has needed repairs. The most recent problem which is right now has lead me to replace the limit switch, gas value transformer and the control board. Nothing seem to work. The point of replacing my other old weather king with a new one was to avoid this headache. Are any of these parts cover? What is covered with unit? PLEASE HELP!!!