What you don’t know about your duct system may be costing you money. Most of the ductwork in your home is built into walls or routed though areas you don’t visit too often, such as the attic or crawl space. Hidden problems can occur as the result of age and deterioration. Others are design shortcomings due to cost-cutting during construction. Here are some telltale signs of deficiencies in your duct system:
- Ducts in unconditioned zones are exposed to acute temperatures during summer and winter. Thermal loss can occur through the metal duct material if ducts lack sufficient insulation. In the central Indiana climate, the U.S. Department of Energy recommend duct insulation to a level of R-6.
- During original construction, duct segments in many areas may not have not been mechanically fastened together but simply sealed with duct tape that deteriorates with age. Duct segments may have worked loose or become disconnected over time, spilling conditioned air into areas like the attic and crawl space and causing major energy loss.
- In an ideal system, each supply duct in a room should have a dedicated corresponding return duct. To cut building costs, however, many homes were built with a single central return, usually located in a hallway, to serve all rooms. When doors to rooms are closed, the air path to the central return is obstructed. This causes increased air pressure in rooms, resulting in leakage of conditioned air through cracks and gaps in the structure.
- Another cost-cutting construction method was to seal up channels inside wall cavities or between joists in the ceiling and use these channels as substitutes for proper metal ductwork. Wood dries with age and contracts, so these channels are often not airtight. In addition, because return systems are under slightly negative pressure, leaks in these areas tend to draw unfiltered, contaminated air into the system from areas like the attic or wall spaces.
With more than 40 years serving Indianapolis homeowners, Mowery Heating, Air Conditioning & Plumbing is your local source for home comfort expertise. Ask us about an evaluation to bring out the hidden defects in your duct system.
Our goal is to help educate our customers in Brownsburg, Indiana and surrounding areas about energy and home comfort issues (specific to HVAC systems).
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