How To Add Central Air To Existing Furnace

San Rafael

(415) 942-6565

Santa Rosa

(707) 452-3464

Adding Central Air Conditioning

Lack of air conditioning in the midst of the heat of the summer months can make indoor air quality unbearable at times. Fortunately, there are many different options you have to add central air conditioning to your existing HVAC unit rather than having to install a separate air conditioning system.

Indoor air quality can be infinitely improved by adding an AC to your existing furnace unit since it works as an air filtration system as well as a cooling system. As the air circulates through the ductwork, the filter will constantly remove dust and debris particles that get sucked up into the system from the air in your home. This can greatly improve the health of your system as well as that of your household in general. The air filtration can also be attached to your furnace or air handler, meaning it can be working to improve air quality throughout any time of the year.

There are a number of things to consider before beginning this process, however, like costs, system size and placement, how to bring cool air to every room, and whether or not there is existing ductwork in your home or not. In today’s article, we will look at all of these factors and more to prepare you for installing your new AC into your HVAC system.

Cost Of Adding A Central Air Conditioner

The typical cost of installing a new system will be between $3,000 and $7,000. You will first need an HVAC technician to perform a survey of the house to see what will be required to install central AC. Costs may also vary depending on whether you need ductwork or not and if you need any additional insulation or sealant to prevent cool air loss.

Overall, the price of adding a central air conditioner depends on your particular home and HVAC system. It is always important to have a professional take a look at your system and perform the HVAC installation so that you can be sure everything is connected correctly. It is also a good idea to consider how long you will be staying in the house or if you plan to sell it soon. In both cases, you could greatly benefit from adding central air conditioning because of the amount you would save on utility costs in the long run.

Components Involved With An Air Conditioning System

When it comes to a new central air conditioning installation, there are many working parts that will have to be connected to the system. There are two major components that are crucial to an air conditioner: the indoor air handler and the outdoor condenser unit.

An indoor air handler is made up of an evaporator coil and a lower and usually resides either in an attic or dedicated HVAC closet. If you have a forced-air furnace, you can install the evaporator coil directly into it and use the furnace blower for air circulation.

An outdoor condenser unit is made up of the condenser coil and fan, as well as the AC compressor. This will usually be located behind or at the side of the house and connected to the handler by two insulated lines that work to circulate refrigerant.

Sizing An AC Unit

It is important to have a properly sized air conditioning unit for your system so that the unit won’t have to overwork itself if it is too small or too big compared to the heat gain in the house. An undersized unit will have to run constantly to try to cool your entire home, while an oversized unit will take a large amount of energy to run that you don’t need to be wasting and go through short cycling. A unit that is too large will also struggle to extract the humidity from the air in your house. Both of these instances will raise your energy bills and drastically shorten the lifespan of your system.

While relying on a professional technician to make the proper calculations for you is smart, it is also a good idea to make some calculations of your own, like the square footage of the area you want cooled in your home multiplied by 20 to get the correct size of the central AC unit you need. Technicians, meanwhile, will perform a cooling load calculation in order to find the heat energy that is removed from the house every hour and, from that, find the requirements to provide cool air to the house.

Efficiency Of Air Conditioning Units

The efficiency of air conditioners is determined by their Seasonal Energy Efficiency Rating, or SEER. The higher this rating is, the more energy efficient the air conditioning unit is, meaning the lower the month-to-month operating costs will be. There are minimum SEER requirements for certain units based on where you live and the age of the system. Though an air conditioner will be more energy efficient in the long run with a higher SEER, a higher SEER will also mean the initial cost of the unit will be a lot more.

Types Of Units

There are two different types of AC units to choose from when considering what system is best for your home. There is a package system, which groups the condenser with the fan and coil. Ductwork connects to this type of unit. These systems aren’t very common and typically act as wall air conditioners.

A split system is where the condenser is outside of the house while the fan and coil are inside. The pipes that connect them carry refrigerant, and in a forced air heating system, they are connected to a cooling coil within the air handler.

The AC system can also go into the furnace plenum that is already there or into one that an HVAC contractor can input. The fan and coil system will usually be placed in the attic to deliver cold air through the ducts if you do not have forced air heat.

Importance Of Ductwork

When installing a central air conditioning system, it is important to know if you have ductwork in your existing heating system. If you are not sure what kind of furnace you already have or if you have ductwork in your home, you can tell by whether or not you have registers, or vents, within your home where warm air comes through. This means you have ducts. If you already have existing ductwork in place, you can connect your central air conditioning to it. It is also possible to have the furnace blower circulate the air from the AC unit.

An important step to take before installing your air conditioner with ductwork is to make sure that all ducts are properly sealed in walls, closets, or attics and maintained for maximum efficiency. This can be done through a manual painting of mastic on the joints and elbows or even an internal duct repair like Aeroseal

If you do not have existing ducts, there will be a few more steps when adding AC to your system. Air conditioning contractors will have to install an air handler in the attic and run ductwork through the house. It will not typically require major construction on your walls and ceilings since most new ducts can be installed by only drilling small holes for the supply and return registers.

Placing Your Unit

Where you set up your air conditioner is important for many reasons. They can be loud, so it’s best not to place them near a bedroom or office. You also do not want to place them anywhere where they will be completely enclosed, since they need room for proper ventilation to work efficiently. They will take out the hot air from the house in order to cool it, so they could overheat from the warm air it exhausts if they are completely covered.

But what about a window unit?

Window units can be an alternative to a central system that some people consider, but there are many drawbacks. A window unit can be extremely loud, and while they can create immense comfort for a single room on a typical hot day, they aren’t as effective at cooling the entire house. Placing window units at every window is a very expensive option and will block out natural light since it will block a portion of the window and therefore also block air ventilation. While choosing the right system for your home is ultimately up to you, it is a good idea to consider the placement of the units when you add air conditioning, because simply where an air conditioner is set up can determine the amount of energy it will use.

Adding central air conditioning to beat the heat in your house can take a lot of steps. You will need to know all the components that need to be installed and the installation costs. You will need to know how to choose the correct size, type, and placement of your system, as well as consider the energy efficiency of the entire system. And it is very important to know if you have existing ducts in your house or if you will need to have ducts put in before adding a central air conditioner.

It is always best to consult with an HVAC professional throughout this process so that you have the proper tools to get the most out of your central AC and not waste energy at any time. Calling a certified HVAC company like John Owens Services can guarantee that you will have a professional central AC installation and that your home will have cool air at a comfortable rate without wasting money on unnecessarily high utility bills.

Take the step to make your home more comfortable this summer by adding central air conditioning to cool every room in the house and remove humidity from the air so you can live with fresh, conditioned air when the weather outside gets hot.

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(415) 942-6565
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(707) 452-3464



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San Rafael
(415) 942-6565
Santa Rosa
(707) 452-3464