Difference between centralized and decentralized heating systems
The HVAC system in your home is either centralized or decentralized. In centralized heating systems, all of the mechanical equipment used to heat the home is located in one place. A heat pump, boiler, or furnace is the most common centralized heating component.
In a decentralized system, the equipment is located in various rooms of the home and outside. An example of a decentralized system is a mini-split. These are often found in office buildings or apartment complexes. They are also gaining in popularity for their operating efficiency.
Whether in your home or a commercial building, selecting the right HVAC system is a significant decision. Determining which of the heating systems is best for you depends upon a number of factors, such as how large of an area you need to heat, the total heat generated inside the enclosed area, the initial installation cost, exterior aesthetics, long-term maintenance, and other considerations. An experienced HVAC contractor can discuss the options available to you and help you decide which kind of system will best satisfy your needs.
Advantages and disadvantages
Most modern homes are outfitted with centralized HVAC systems. However, decentralized systems are gaining in popularity. Their overall advantages are that they:
- Are easier and cheaper to install.
- Allow for easier individual control of separate spaces.
- Can be more affordable when dealing with large spaces.
- Take up less space due to the absence of ductwork.
Some of the considerations in deciding between centralized or decentralized heating systems include the following:
Cost and energy efficiency
The initial expense of a centralized system is higher than a decentralized system. In a centralized HVAC system, the heat is delivered through a system of ductwork. When the heat is on, the entire house is heated at the same time because of the ductwork, including rooms that are seldom used. This means the operating costs are higher. The system has to move air over long distances. Poor duct connections, holes, or leaks can lower the system’s efficiency.
You might think you can save money by closing vents to unused rooms in wintertime. However, your centralized system is designed to serve a minimum amount of square footage for optimal performance. If you close the vents in some of the unused rooms to save energy, you can actually put more strain on a system that is designed to service more square footage.
A decentralized system is cheaper initially and more efficient to operate. With a decentralized HVAC system, the air is streamed directly into the specific room you want to heat. The air handlers are installed in the rooms that need heating so you do not waste energy heating the entire place.
Installation
Installing a centralized HVAC system is more expensive than a decentralized system due to the amount of ductwork involved and the size of the system itself. Not only is installing ductwork expensive, it adds to the amount of construction time.
By comparison, a decentralized heating unit is much less expensive and less complex to install. Only the air handler is located indoors; the rest is installed outside. No ductwork is required. It needs only a small hole in the wall where the conduit will pass to connect the indoor with the outdoor units.
If you need to replace an HVAC system in a home or building with ductwork in good condition, a centralized system may make the most sense. If you are adding on with new construction, you may be able to save money by avoiding new ductwork in the addition and choosing a decentralized system for it.
Ease of maintenance
A centralized system has the advantage when it comes to ease of maintenance. All of the components are in one location, making accessibility more convenient. In contrast, a decentralized system has working components scattered throughout the facility. Trying to pinpoint the location of a problem can make service difficult. Even routine maintenance can be a big job. In a large apartment or hotel complex with a decentralized HVAC system, the system is modular, made up of many separate compressors and heating components, each needing to be maintained.
Meeting varied demands
A decentralized system usually performs better under varied conditions. It is better able to meet the demands of different tenants in different parts of the building throughout the day and night. A centralized system can result in disparity from one side of the facility to another. Performance can be improved by dividing the system into multiple zones, though at some point, you can have numerous thermostats and lose the convenient maintenance advantage that a centralized system can offer.
Aesthetics
Where to house the exterior components is an important consideration. With a centralized system, the equipment can be tucked away in a screened area or mounted on top of a rooftop out of view yet readily accessible for service. In contrast, a decentralized system may have its mechanical equipment sited in numerous locations around the property, and may not be completely hidden from view. In your home, indoor air handles are mounted in plain sight either on the ceiling or wall of the selected rooms.
Other factors to consider
In answering the question of whether a centralized or decentralized system is best for your needs, other factors may be important. They include:
- Source of available power – gas, propane, electric, or other.
- Your local climate.
- Existing heating equipment in your home.
- The layout of your home.
- The land your home is situated on.
- The size of your home.
- Whether your home is in seasonal or year-round use.
Consult an experienced HVAC contractor for advice
For advice on which of the heating systems is best for your needs, talk to a reputable HVAC contractor. Your HVAC contractor can help you identify the most important considerations and suggest which of the heating systems would be the most suitable. Call an experienced HVAC contractor before the cold weather arrives to schedule your heating maintenance, repair, or installation service.