The Condenser - A Closer Look at Insulated Blades

Heat transfer can throw off a balanced system. When temperature control is key, consider dampers with insulated blades. Learn more with the Condenser.

Temperature Control

HVAC systems bring comfort to the indoors. Whether you need to cool down or warm up, the HVAC system keeps temperatures exactly right when you step inside. In certain areas, you may have trouble keeping cool or warm air. In other areas, it may be vital to maintain a specific temperature throughout the day. For these applications, you will need a way to insulate your system. Insulated blades can help in these scenarios.

There are two common blade shapes for control dampers: single-thickness blades and airfoil blades. Insulated blades often take the airfoil shape. For airfoils, two pieces of sheet metal are combined into a curved shape that resembles the wing of an airplane. There are structural supports along the interior of the blade to keep the blade’s shape.

Insulated blades take this design a step further. Manufacturers inject insulating foam in between the two pieces of metal, filling the core of the blade. This insulation is commonly made from fiberglass. MCDLG uses a two-part mixture of polyurethane for our insulated damper line.

Whatever it’s made from, the insulation is meant to prevent heat from passing through the blade. This is commonly referred to as thermal transfer.

Mitigating Thermal Transfer

Heat passes through uninsulated blades even when the damper is fully closed. This transfer can make it difficult to control temperatures in connecting ductwork, as the heat bleeds from one section to the next. Constant fluctuations between hot and cold create condensation in your ductwork, which can corrode metal parts or grow mold in the airstream. Minimize thermal transfer in areas that require precise temperature control. Insulated blades prevent heat from passing through. The core insulation absorbs the heat, much like the insulation in the walls of a house. When fully closed, the hot air stays on one side of the damper.

Insulated blades will only prevent thermal transfer at the face of the damper: heat can still bleed through the frame. For a fully insulated damper, look for “thermal breaks” in the frame. A thermal break frame will have additional insulating features inside the frame that prevent thermal transfer across the frame.

Always review the requirements of your application before selecting a damper. If you have areas that need insulating, then consider a control damper with insulating blades.

For more on control dampers, check out these Newsstand article:

• Air Leakage - The Performance Killer
• Five Specialty Dampers for HVAC Design
• Understanding Your Dampers

MCDLG & Continuing Education

Want to know more? MCDLG offers a free self-paced course on control dampers.  

Learn the basics of control dampers with "An Introduction to Air Control Dampers", including their components, what they do, where they go in an HVAC system, and guidelines for installing and maintaining your control dampers. 

This course provides continuing education credits for a variety of institutions, including ASHRAE's PDUs. Learn and earn at your own pace. Visit the MCDLG Campus Portal today!

Do you have a question on something we haven't covered here? Or maybe you need help from industry experts? MCDLG can help. Contact us by clicking on the button below.