A Complete Guide to Central Air Conditioning Installation

Air conditioning systems are expensive and complex. Getting the best performance and longevity from yours requires a thorough installation process.

Central air conditioners consist of two key components — an evaporator coil inside your house and the condenser unit outside. An improperly sized AC can cause premature wear, higher energy bills and uneven indoor temperatures.

Cost

Central air conditioning systems pull air from the outdoors, cool it and then push it throughout your home through ducting. This makes it more expensive than cooling with window units or portable ACs, but you can get rebates from DTE if you upgrade to a high-efficiency model.

The cost of an AC unit will depend on your home’s square footage and the type of air conditioner you choose. It will also be affected by whether you have ductwork and the condition of the ducts. A contractor will need to perform a Manual J load calculation to determine what size AC unit you need.

Hiring an HVAC professional to install your new system can save you money in the long run. Look for one who has good reviews and offers upfront pricing. If you’re shopping around for a price, be sure to get at least three estimates. And remember that you should never cut corners when it comes to an important home improvement project like this.

Energy Efficiency

Many factors impact the energy efficiency of a central air conditioning system. Your contractor will calculate the cooling capacity your home requires based on square footage and other variables. For instance, new insulation or windows may reduce the amount of air needed to cool your home. Your contractor will also look at the ductwork and thermostat for energy efficiency ratings and recommend improvements if necessary.

The energy efficient equipment you choose can significantly lower your utility bills and energy costs. The ENERGY STAR rating system helps you identify efficient units and you can check the website of your electric utility to learn about rebates that are available for upgrading to a high-efficiency unit.

Unlike window units, central air conditioners have components that can be installed only by licensed professionals. It’s too complex and risky to attempt DIY installation. Handling the refrigerant and connecting the electrical require specialized skills. Additionally, you could void the warranty or run the risk of a dangerous leak.

Installation

It’s important that your contractor discuss what kind of air conditioning system would work best for your house, including whether it makes sense to upgrade ductwork or install a new thermostat. The contractor should also ask you how much energy efficiency matters to you.

Central air conditioners use a series of ducting and registers (openings) to carry cool air throughout your home. If the ductwork is old or damaged, your contractor will inspect it and replace or repair it as necessary.

Before your contractor starts any work, he should get any necessary permits or inspections from your city or county. It’s also a good idea to check that the company you hire is licensed, bonded and insured. Any contractors who handle refrigerant or equipment that contains refrigerant should have EPA certification. These are required by law. In addition, the unit’s condenser must be kept 3.3 feet away from anything that emits electrical noise, such as TV antennae or power lines.

Maintenance

If you choose to install a new air conditioning unit, hire a professional in heating, ventilation and air conditioning, or HVAC. The installation process includes pouring a concrete pad to place the outdoor unit, and installing ductwork. A professional may also need to make modifications to the roof to accommodate the new unit.

The installer will drain the refrigerant and disconnect the old air conditioner’s line set, which is then reconnected to the new one. An exterior shutoff is installed for the air conditioner, and a service disconnect box is mounted near the unit.

The installer will connect the high-voltage electrical wiring to the service disconnect box and the low-voltage wires to the thermostat. A new evaporator coil and blower are also installed inside the home, usually in the attic or an existing HVAC closet in retrofits. The ductwork may need to be resealed, as air leaks can reduce efficiency and lead to higher energy bills.