Central Heating and Air
Central Heating and Air Conditioners
Modern central heating and air conditioning systems offer exceptional comfort and energy savings while reducing a building’s overall environmental impact. When considering an upgrade or replacement, it is important to understand the different equipment options, performance levels and energy consumption ratings of central heating and air conditioners.
To maximize operational efficiency and enhance indoor comfort, a heating and cooling system must be sized to meet the unique structural characteristics of the building it will serve. Air conditioners that are oversized will short cycle, which can result in poor humidity management, uncomfortable temperature fluctuations, and reduced ability to get rid of stale air. Undersized equipment may not have the capacity to satisfy the cooling load and the extended runtime can lead to repeated breakdowns and premature failure. In extreme temperatures, undersized systems rarely satisfy the heating or cooling demand.
Homeowners should avoid dealers who size equipment according to outdated "square feet per ton" formulas. Replacement units should never be quoted before a thorough load calculation analysis is completed on the building. Heating and cooling contractors who do not utilize ACCA Manual J load calculations throughout the design phase should be avoided.
Which Central Heating and Air Conditioning System is Right for Me?
Central air conditioning and heating systems are offered in many different configurations. When selecting A/C equipment, it is important to work with a qualified contractor who understands the impact of local climate conditions and fuel costs on system performance.
Split Systems: A split system is characterized by a separate outdoor condensing unit and an indoor furnace or air handler. Refrigerant lines connect the two parts of the system and transfer heat energy through the refrigeration cycle. Homeowners with existing radiant heating systems can purchase a straight evaporator coil and blower, and those needing heat can choose a forced air furnace option.
Packaged Units: Packaged units combine the condensing coil, compressor, evaporator coil, and the blower all within a single enclosure. Units can be placed on the ground, but they are usually installed in rooftop applications where space is limited.
There are three types of available packaged units including heat pumps, gas-electric models, and straight cooling units.
Air-Source Heat Pumps: Air-source heat pumps operate in a manner that is similar to a traditional central air conditioner. One of the features that distinguishes a heat pump from a conventional system is the inclusion of a device called a reversing valve, which changes the direction of the refrigerant flow to provide both heating and cooling from a single system.
Geothermal Heat Pumps: Ground-source heat pumps provide numerous benefits when compared with conventional air-source equipment. The geothermal unit is connected to a series of pipes buried in the earth in a closed-looped configuration. Consistently stable underground temperatures promote exceptional heat transfer efficiency. In addition to lower operational costs, there are often various incentives for the installation of ground-source HVAC systems.