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AIR CONDITIONING & HEAT PUMP SYSTEMS
A/C - HEAT PUMP CONTROLS & SWITCHES
AIR CONDITIONER COMPONENT PARTS
AIR CONDITIONER TYPES, ENERGY SOURCES
AIR FILTER EFFICIENCY
AIR FILTERS, FIBERGLASS PARTICLES
AIR FLOW MEASUREMENT CFM
APPLIANCE EFFICIENCY RATINGS
BLOWER DOORS & AIR INFILTRATION
BLOWER FAN CONTINUOUS OPERATION
BLOWER FAN OPERATION & TESTING
BOOKSTORE - Air Conditioning "How To" Books
CAPACITORS for HARD STARTING MOTORS
CLEANING & Legionella BACTERIA
CHINESE DRYWALL HAZARDS
CONDENSATION or SWEATING PIPES, TANKS
DEFINITION of Heating & Cooling Terms
DEW POINT CALCULATION for WALLS
DEW POINT TABLE - CONDENSATION POINT GUIDE
DIAGNOSE & FIX AIR CONDITIONER / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DUCTS - Asbestos
DUCT INSULATION, Asbestos Paper
DUCT INSULATION for SOUNDPROOFING
DUCT SYSTEM NOISES
DUCTS, Asbestos Transite Pipe
DUST, HVAC CONTAMINATION STUDY
ELECTRIC MOTOR OVERLOAD RESET SWITCH
EVAPORATIVE COOLING SYSTEMS
FAN LIMIT SWITCH
GAS EXPOSURE EFFECTS, TOXIC
GAS DETECTION INSTRUMENTS
HEAT LOSS (or GAIN) in buildings
HEAT LOSS (or GAIN) INDICATORS
HEAT LOSS R U & K VALUE CALCULATION
HEATING SMALL LOADS
INSPECTION CHECKLIST - OUTDOOR UNIT
INSPECTION LIMITATIONS, A/C SYSTEMS
LEED GREEN BUILDING CERTIFICATION
LOST COOLING CAPACITY
LOW VOLTAGE TRANSFORMER TEST
MOTOR OVERLOAD RESET SWITCH
MOLD in AIR HANDLERS & DUCT WORK
OPERATING COST, AIR CONDITIONER
OPERATING DEFECTS, AIR CONDITIONING
REPAIR GUIDE, AIR CONDITIONERS / HEAT PUMPS
REPAIR & DIAGNOSTIC FAQs for A/C
THERMOSTATS, HEATING / COOLING
THERMOSTATIC EXPANSION VALVES
WATER COOLED AIR CONDITIONERS
WINDOW / WALL AIR CONDITIONERS
WINDOW / WALL A/C SUPPORTS
Gray HVAC flex-duct failures: this article explains Alloy Systems™ brand gray flex duct failures that appear as loss of the gray plastic duct covering due to brittleness that appears to be caused by exposure to heat (such as in a hot attic), with references to product failures by several manufacturers of flexible duct work, including Alloy Systems™, Goodman™ flex duct, Owens Corning™ flex duct, Owl™ flex duct. We believe that none of these defective flex duct products is currently sold (2010) but both may be found in older homes. Note: not all Owens Corning flex duct products share this defect and disintegration problem.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Air conditioning duct system defects include a remarkably wide range of errors, from failure to supply cool air or failure to even circulate air in the building, to health hazards such as use of asbestos material in or on duct work, to very dangerous conditions such as drawing heating equipment combustion gases into the building cooling (or heating) air.
The first field reports we received of gray flex duct disintegration bearing the Alloy Systems brand was in 2010, reported by Eric Van De Ven, a South Florida home inspector. The Alloy Systems flex duct photos in this article were provided by Mr. Van De Ven and were taken in a South Florida home built in 1984.
Readers concerned with deteriorating plastic and fiberglass-covered flex duct in buildings should see these duct failure reports: ALLOY SYSTEMS FLEXDUCT, and GOODMAN GRAY FLEXDUCT, and OWENS CORNING FLEXDUCT and OWL FLEXDUCT. Also see our more broad category: DUCT SYSTEM DEFECTS.
This article explains Alloy Systems™ brand gray flex duct failures that appear as loss of the gray plastic duct covering due to brittleness that appears to be caused by exposure to heat (such as in a hot attic), with references to product failures by several manufacturers of flexible duct work, including Alloy Systems™, Goodman™ flex duct, Owens Corning™ flex duct, Owl™ flex duct. We believe that none of these defective flex duct products is currently sold (2010) but both may be found in older homes. Note: not all Owens Corning flex duct products share this defect and disintegration problem.
The loss of the protective plastic covering on flex duct poses several concerns including loss of the duct insulation, increased air conditioning system operating costs, and possibly air leaks out (if supply ducts are damaged) or un-wanted attic debris leaks in (if return ducts are damaged), and in-duct condensation in the HVAC system leading to mold and indoor air quality concerns.
This Alloy Systems gray flex duct or "flex duct" air conditioning duct work material is a defective product. In hot attic spaces or where exposed to UV light, the plastic of this flexible air conditioning duct material disintegrates leaving its fiberglass insulation exposed to also disintegrate, leak, or possibly blow into the building living space. Replacement of the duct work is required - a significant expense. - Thanks to Eric Van De Ven for these photos of Alloy Systems gray flex duct disintegrating in an attic.
Where this duct is found in a building it should be replaced. When a heating or air conditioning flex-duct product has lost its exterior plastic covering the effects are these:
Below at Technical Reviewers & References we include Flexible Air Duct Installation Manuals, standards, guidelines, and contact information for several flexible air duct manufacturers as well as access to Flexible Duct Performance & Installation Standards provided by the Air Diffusion Council.
Readers concerned with deteriorating plastic and fiberglass-covered flex duct in buildings should see these duct failure reports:
Frequently Asked Questions (FAQs)
Questions & answers or comments about flexible HVAC duct deterioration, leaks, and problem products
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.