Very poor instulation of High Eff LENNOX furnace

Furnace was installed incorrectly, water trap upside down so furnace will not drain correctly and air intake is to small for this size of furnace, should have been made larger. Now furnace barely works (computer chip keeps shutting it down) after only three years, have to keep turning power off and on to make it work, which means when I'm not at home my house could freeze up (lucky weather hasn't been too cold this winter). Have contacted them and they don't seem to want to fix this problem correctly that they caused! Another company will fix it , but no one wants to pay the bill. When someone makes a error they should fix it at their cost!! These furnaces are not cheap!!!!