The weather here in Northorn California has been in the high teens and low twenties. On my way to work this morning my heater is blowing warm air and it never got hot enough to fully defrost the windsheild or keep the inside of the car very warm. Is it because my t stat is 180 or do I have another problem. I am thinking I need to step to a 190 for the winter? Will this help keep my car toasty? Thanks for the help.