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AIR CONDITIONING & HEAT PUMP SYSTEMS
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BLOWER DOORS & AIR INFILTRATION
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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
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DIAGNOSE & FIX HEATING PROBLEMS-BOILER
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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
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GAS EXPOSURE EFFECTS, TOXIC
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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
Goodman gray flex duct HVAC ductwork deterioration: this article discusses Goodman™ brand gray flex duct disintegration failures with references to product failures by manufacturers of similar flexible duct work products. We include photographs illustrating heat-damaged flex-duct covering materials and we explain the implications on home energy costs when this material is installed in buildings. We include, for comparison, other gray plastic covered flex-duct materials that do not appear to disintegrate in hot attics, using Certainteed's Certaflex-G25 as an example.
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.
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.
This article describes Owens Corning Valueflex™ 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 Goodman 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 Jon Bolton for these photos. of Goodman 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.
Other Gray Flex-Duct Products Surviving Attic Heat
CertainTeed Certaflex-G25 Flexible HVAC Duct : Attic Inspection
An example of gray flex duct that is surviving the heat in hot attic spaces includes these CertainTeed Certaflex-G25 Class-1 Air Duct material. Eric Van De Ven, our flex duct detective in the field, contributed these photographs. Mr. Van De Ven explained
You will notice in our second photo (above right) that while the flex duct in this home was not obviously heat-deteriorated, it had been cut or mechanically damaged. We recommend patching minor tears with a plastic or foil duct tape.
Certainteed makes a wide range of building insulation products including the flex-duct above and also FIBERGLASS DUCT, RIGID CONSTRUCTION.
List of plastic-covered flexible HVAC duct products that appear to deteriorate in hot spaces like attics
Readers concerned with deteriorating plastic and fiberglass-covered flex duct in buildings should see these duct failure reports:
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Technical Reviewers & References
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