HVAC - Heating, Ventilation, & Air Conditioning
The first step in getting a new air conditioner installed is determining what size you need. You don't want one without sufficient capacity to cool and heat your home. Installing an HVAC system that's too big, or too small can be more expensive to operate and less comfortable. Your HVAC contractor should explain all the steps, and details that are necessary in determining the proper heating and air conditioning system for your home.
HVAC System Design
HVAC system design for residential homes is performed using software in accordance with set standards. The ACCA, or Air Conditioning Contractors of America organization sets standards for the design of air conditioning systems and associated HVAC duct sizing and duct design. These design standards are found in manuals that are published by the ACCA. The manual that is used for the sizing of residential equipment is known as Manual J. The manual that is used for the design of residential duct systems is known as Manual D. The design methods outlined in these manuals should be followed by your HVAC contractor. Even if your just replacing an existing air conditioning system, the contractor should perform Manual J and Manual D calculations to determine exactly what the correct equipment and ducts should be for your home. Anything less should be a "red flag" that you are not dealing with a professional.