By Alexandra Anderson McAllen HVAC is a heating and cooling system that is generated to produce both cold and hot air. However, you still need to learn all about it so that you will not waste time when you will start working on it. That is why you need to read all about it or ask information from other people. Making the load calculation is what you need to do first. You can either use the CD that comes with it or you can just download any software that works the same as the CD. Just remember to choose the ones that are free so that you it will not be costly on your part. Location is the next thing that you need to look for because this one of the vital things that you need to look into. The location that you want is somewhere that would be good for your coil unit. It can be in your attic, garage or other places that are well protected and safe. You need to cut the air opening since you cannot proceed with the next step if you do not do this. If you talk about the locatio...