A Step-by-Step Guide to Air Conditioner Installation

August 9, 2021
AC Installation in Roseville, MI

Installing an air conditioning unit can be an uphill task, especially if you’re not a specialist in the field. You will need extensive knowledge of air conditioners and how to install them. Because this is a difficult job, you will, most likely, require an expert to install your AC system and ensure it functions efficiently with little to no hiccups.

At C & C Heating & Air Conditioning, we pair you with our qualified HVAC technicians, who can offer you advice on the best air conditioner for you. We also provide air conditioner installation services when required. There are various steps to the installation of a new air conditioner.


Our HVAC specialist will come to assess your home and determine what air conditioner works best. The domestic or split system air conditioner is the most common choice for households. The system comprises an indoor unit and an outdoor unit. Pipes that pass refrigerant through the system also need to be installed to play an integral role in providing cool air. The domestic unit allows you to cool multiple rooms at a go, unlike the single-room air conditioner, which only cools one room.

At this stage, our technicians will also identify where they will fit your new system. Newer air conditioners are larger than the older models, allowing for a larger coil that makes your air conditioner more efficient. The current space of your air conditioner may therefore not accommodate the new one.

Removing the Existing Outdoor Unit

Our specialists will use a recovery machine and tank to remove the refrigerant in the old central air conditioner. This method is necessary because it is unlawful to vent refrigerant into the air openly. Using these pieces of equipment allows for the safe removal and proper handling of the refrigerant pipes. Our technicians will then disconnect the wiring in the old system, enabling them to remove the system altogether.

Preparing the Pad for the Outside Unit

This process involves replacing the pads of the old outside unit. A composite pad is recommended rather than a concrete pad because it can sit outside for as long as the air conditioner’s lifetime. The concrete pad is likely to shift drastically, leading to cracks. Repairing it may be difficult. Composite pads can also absorb vibrations from the unit, reducing noise from the unit. Once the outdoor unit is installed and connected, moving it can lead to damage; however, the composite pad can help avoid this damage if there is any need for leveling.

Removing and Replacing the Indoor Evaporator Coil

There are two variations of evaporator coils where one has a case, and the other is uncased. A cased coil is highly recommended as it comes with an insulated cabinet with removable panels. These panels provide access to the coils. Its design allows the evaporator coil to sit on the furnace, making repairs and modifications easy. Our technicians will disconnect the metal plenum before they install a new evaporator coil.

When using an uncased coil, the supply plenum requires preparation work before a new coil installation. This prevents damage from occurring to the furnace or coil. The drain pipe on the coil is plastic, and therefore a rail needs to be installed, creating distance between the furnace and the coil. Our technicians then install the coil on the plenum. If it is bigger than the coil, they build a sheet metal pan to cover the extra space. They will then build a plenum door to protect the coil from damage.

Removing and Replacing Refrigerant Lines

The refrigerant line comprises two copper lines through which the refrigerant travels to the outside condenser and back into the evaporator coil. The refrigerant travels alongside oil, and old systems use different oils from new ones. It is of paramount importance that these oils do not mix as this can damage the new air conditioner. If there are obstructions such as walls on the old lines, our specialist may set up a new line or reuse the old line. The technicians will have to flush and clean the old lines and ensure the line pressure is working; however, we do not recommend reusing old lines unless necessary.

Our licensed technicians will install hangers around the area the refrigerator lines pass through to ensure they stay in place. They will then roll out the lines and push them close enough to reach the valve of the outside unit. The line will run from the air conditioner condenser to the indoor evaporator coil placed on top of the furnace. They will also install a small low-voltage control wire connecting the thermostat to the furnace and the outside unit. This will allow you to turn the air conditioner on and off.

Setting Up the Outside Unit

The technicians will then set up the air conditioner condenser on the composite pad they had set up earlier. They will also inspect it for any damages that may have occurred in transit. If it’s in perfect shape, they will fit the line set up that was installed in the previous step in the service valve of the unit. Once fitted in the valve, they will melt the copper line set, service rod, and a filler rod used to join the two together, forming a leak-free connection.

Installation of the Filter Dryer

A filter dryer is installed in the air conditioner condenser as it absorbs moisture and provides physical filtration. Many manufactures recommend that the filter dryer installation remains close to the expansion valve at the indoor coil. This helps protect the filter dryer from bad weather that could cause it to rust.

Installation of Wiring

Our specialists will mount a new service disconnect box using the existing power supply from your electric panel. There are two types of disconnect boxes: the fused or the non-fused disconnect box. The fused box allows for overcurrent protection, and most manufacturers recommend it. The non-fused box is fit for use if the breaker matches the maximum overcurrent protection listed by the air conditioner manufacturers.

Condensate Drain Line Installation

Moisture produced during the cooling process travels down a PVC pipe that connects to the evaporator coil. The evaporator has a primary and secondary drain, with the primary condensate drain traveling from the coil to an appropriate drain or condensate pump. Our specialist installs a condensate pump if the house does not have a floor drain.


The final step involves testing the installed system. Our technicians will turn on the air conditioner for 15 to 20 minutes. This is enough time for the refrigerant to flow through the system and start the air conditioning process. They will then commission it, ensuring everything is in great shape before leaving, providing you with peace of mind. Commissioning the unit also ensures the manufacturer’s warranty is in full effect.

To learn more about air conditioner installation services, contact C & C Heating & Air Conditioning today. Besides installing ACs, we also offer heating, cooling, indoor air quality, UV lights, and water heater services to the residents of Detroit.

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