Air Conditioning System FAQs

If you currently have a furnace in your home with ductwork, then the easiest and most economical way to get cooling is likely using an A-coil and outdoor condenser or heat pump. An A-coil is a small piece of equipment that sits on top of your furnace and as the air passes over the coil, it provides cooling to your house. An outdoor unit is the real engine of the cooling system. It is also known as a condenser. A heat pump is also an option if someone wants to have some supplemental heating capability added to the cooling system. Check out our heat pump information for more details. These split air conditioning systems are usually the easiest to replace and install since the majority of the system (furnace, ductwork, vents) is all existing. But be careful, a cooling system is much more susceptible to poor performance or failure due to a poor duct design/installation because the cool air is denser, heavier, and harder to move. So the duct design has to be right or you’ll never be comfortable. This type of cooling system also has limited control over individual spaces unless the top tier modulating type of equipment and zoning is used.

Very similar to the furnace and A-coil, these units are separate from the furnace and can be common with boilers for a heating system. An air handler would be attached to a ducting system and would deliver the cool air through that ductwork and vents. Air handlers can also be connected to condensers or heat pumps. As with the A-coil and furnace, air handler type split air conditioning systems can be susceptible to poor duct design as well as limited control and comfort. A hydronic air handler is also an option, which has a hot water coil that gets heating capability from a boiler in the home/building.

When people say ductless, the wall unit is typically what they picture in their minds. Ductless offers the best control over individual spaces as well as comfort. Many manufacturers have very efficient heat pumps as their primary offering, with cooling only options being a dropdown option. Ductless systems are one of the best options for having efficiency, control, and comfort in the home. Please visit our ductless mini-split installations page for more information about these systems.

A much less known system option than others, ducted mini-split systems give a customer close to all the benefits of a conventional ducted system as well as close to all the benefits of a ductless mini-split system. These options can do one to four rooms with one small piece of equipment and limited ducting installed. The efficiencies are high and they are very capable of providing the desired comfort that one would expect from a ductless system. The downside is that they are more intrusive with trying to install even a limited amount of ductwork into a space, and they are typically limited to conditioning multiple rooms, especially when those rooms are smaller. They are a great option for people who want the comfort, efficiencies, and control of ductless systems but don’t want, or have no space for, wall units.

Because window air conditioners are inexpensive and New Hampshire was traditionally thought of as not needing air conditioning for much of the year, many homes were built without AC system, and window AC units were the answer. However, people are quickly becoming more concerned about air quality and comfort, and, in those two categories, window units fail. Window air conditioning units are not efficient at all, primarily due to the size restraints of the coils and casing as well as the voltage that they can run on. Window shakers are noisy and generally are not able to condition more than one small space each. The one benefit is that they are very inexpensive. If something goes wrong with the unit, it is generally less expensive to buy a new one than it would be to try to have the old one repaired.