Does Central AC Tubing Need to Be Insulated?

Air Conditioning Tubing

• Central air conditioning systems operate off an outside condenser unit and an air handler unit or AC coil, which works alongside a home’s furnace system. Air conditioning systems deliver coolant to the air handler and warm air to the condenser through tubing that runs between the condenser unit and the air handler. As insulation helps to improve a furnace’s heating efficiency, it can also improve an air conditioner’s efficiency by preventing cool air or warm air from escaping from AC tubing lines.

Moisture Buildup

• Areas where AC tubing enters condenser and air handler units can develop moisture buildup, or condensation problems, from surrounding air temperatures. Condensation problems occur when cool tubing surfaces contact warm exterior air. When this happens, warm air molecules become cool, which causes them to release water vapor that appears as condensation on tubing surfaces. With insulated AC tubing, there’s less of a temperature difference between exterior air and insulation surfaces. This reduces the likelihood of moisture buildup or at least reduces the amount of condensation that forms.

Structural Damage

• When left unattended, condensation from AC tubing lines can cause structural damage to the home as well as to air conditioning and heating system components. Properly insulated lines means insulation surfaces remain intact with no gaps or crimps in the insulation material. Where AC tubing enters the air handler unit, breaks or gaps in insulation materials can lead to condensation and water dripping onto a furnace’s heat exchanger compartment. These conditions cause rust and corrosion to form along heat exchanger walls, which can hamper a furnace’s gas and smoke combustion processes. Where AC lines pass through humid areas in the home, water from condensation can damage drywall and wood surfaces and encourage mold growth.

System Efficiency

• Insulating AC tubing lines can help improve an air conditioner system’s efficiency in terms of how hard it has to work to keep a home cool. Areas where heavy condensation is present cause the system to work harder at maintaining coolant temperatures, which affects the room temperatures in a home. This occurs as exterior heat enters coolant lines and increases coolant temperatures. These conditions lead to higher utility costs as the system works harder and longer. Insulating AC lines at primary connector points, such as condenser and air handler junctions, can help improve system efficiency.