It's good to have your furnace and the ducts in your home inspected regularly; usually this means every year, but you can check the owner's manual of your particular furnace to note when the manufacturer recommends it in your case. However, between those inspections you might want to check for signs that your furnace is leaking or that your home's ductwork needs repair or maintenance. Note that your furnace doesn't need to quit altogether or only blow out cold air to need some attention, so consider a few surprising signs that it may be time to call a contractor.
If you want to add an AC to your tiny home, you have a few different options. Two of the smallest and most convenient options you may want to consider, however, are portable ACs and ductless mini split systems. Here's a look at how these two types of systems measure up in different categories:
If you opt for a mini ductless system, you will have to have a professional wire in the AC for you.
If you own a restaurant with a commercial kitchen, you need to think carefully about the ventilation. The exhaust fan in your kitchen takes up air and cooking fumes, and you have to replace that air through your HVAC system. If your fans remove too much air, you may end up with negative air pressure, which essentially "vacuum" seals doors shut, prevents smoke from leaving the kitchen and creates other issues.