It is very important to make sure your HVAC units work on your car. I learned this the hard way last winter when I had to take a long trip through a snowstorm. Two days before I left for the trip, I noticed that the heater in my car was not working right. When I turned on the heater, it would sometimes start blowing out cold air like the air conditioner was on. I looked at the air conditioner in my car and the furnace and didn’t see anything out wack. I took my car to my friend’s house who is an HVAC technician. He took a look at the air conditioner and furnace in my car and told me I needed a few new parts in order to fix the HVAC units. Since I was leaving the next morning to go on my trip, I knew I didn’t have enough time to get the parts on an online HVAC store, so I drome to a heating and cooling business looking for the parts for the air conditioner and heater in my car. After searching the entire store and asking one of the HVAC technician employees for help, I was told that the heating and cooling store was out of the parts that I needed. I decided to go on my trip anyway, not too worried because my heater in my car still worked, just not very well. Half way through my trip, the heater in my car stopped working completely and the air conditioner kicked on. I turned both the heater and air container off and decided to just continue without. That was the most bone chilling car ride I have ever had.