Definition:
Duct leakage: Duct leakage refers to the unintended escape of conditioned air through holes, cracks, or poorly sealed joints in the ductwork of an HVAC system. This loss of treated air not only reduces the overall efficiency of the system but also leads to increased energy consumption and higher utility costs as the HVAC unit must work harder to maintain desired indoor temperatures.
Additional Facts
- Energy Loss: Leaky ductwork can result in up to 30% loss of conditioned air, significantly reducing the overall efficiency of an HVAC system.
- Pressure Imbalance: Holes in ductwork can create pressure imbalances, causing some rooms to be over-conditioned while others remain uncomfortable.
- Indoor Air Quality: Gaps in ductwork can allow dust, allergens, and other contaminants to enter the system, negatively impacting indoor air quality.
- Increased Utility Costs: Air leaks force HVAC systems to work harder and longer, leading to higher energy consumption and increased utility bills.
- Condensation Issues: Leaky ducts in unconditioned spaces can lead to condensation problems, potentially causing mold growth and structural damage over time.
Fundamental Mechanisms
| Mechanism | Purpose | Key Components | Critical Issue | Impact of Failure |
|---|---|---|---|---|
| Duct Sealing | Prevents air leakage from ductwork | Mastic sealant, metal tape, gaskets | Deterioration of sealants over time | Reduced system efficiency, increased energy costs |
| Duct Insulation | Maintains temperature of conditioned air | Fiberglass, foam board, reflective insulation | Insulation compression or moisture damage | Heat gain/loss, condensation issues, mold growth |
| Duct Support System | Maintains proper duct alignment and prevents sagging | Hangers, straps, brackets | Loosening or corrosion of support hardware | Duct separation, increased air leakage, structural damage |
| Duct Joints and Connections | Ensures airtight connections between duct sections | Flanges, clamps, sheet metal screws | Loosening of connections due to vibration or thermal expansion | Air leakage at joints, reduced airflow, system inefficiency |
| Duct Pressure Balancing | Maintains proper air distribution throughout the system | Dampers, registers, grilles | Improper balancing or stuck dampers | Uneven cooling/heating, comfort issues, increased energy use |