1. Do you perform a heat load on my house before you decide how big of an air conditioner I need.
Just because you might have a 4 ton AC unit doesn’t necessarily mean this is the correct tonnage for your house. So many contractors use rules of thumbs and guesstimates, and may not be correct. If your unit is too large it won’t have the runtime to remove humidity. If it’s too small, it will run continuously and will not cool very well.
2. Is my duct work sized properly?
Units are designed to move so much air. Your duct work must be sized to handle that amount of air.
Not enough duct work, or too small of duct work, and you can’t move enough air through it. This can cause hot and cold spots or may cause your unit to continually freeze up. This is caused by air staying in the coil section too long and slowly getting colder and colder until icing occurs. This kills the compressor prematurely. Often times a homeowner might choose to replace a compressor and never actually address the real problem.
Too much duct work and the air delivery system doesn’t get the air where it needs to go. It all may go to the room closest the the unit following the path of least resistance. Air needs to be forced to the farthest ducts by static pressure.
3. How do I know your a reputable hvac contractor?
Ask to see license, and Insurance. Ask if they are pulling permits, so work can be inspected by a third party. Do they have a storefront? It’s easier for a chuck in a truck working out of his barn to disappear and never to been seen again than someone who is established and is an active member of the community, maybe ask what they have done to promote their community and promote their trade.
4. Ask for references
All contractors should be able to give you names of other customers near you that they have worked for. Call and check them out.
5. Do you ask for any money up front?
If a contractor doesn’t have the means or credit with his wholesale companies to purchase your equipment before the install. You might want to reconsider.