InspectAPedia ^TM

Proper Placement of Heating or Cooling Registers & Ducts AirCondAPedia © Enter your search terms Submit search form   Search This Website - InspectAPedia.com

• How to Locate Heating or Cooling Registers & Ducts
• Air Conditioning (or Heating) Duct Defects
• Duct installation defects, safety hazards

This chapter of "How to Inspect the Central Air Conditioning or Cooling System" describes the Proper Placement of Heating or Cooling Registers & Ducts and addresses problems such as mis-placed or missing air conditioning cool air supply or return air registers, improper cooling duct routing, cooling (or heating) air duct corrosion, and defective heating or cooling duct work. © Copyright 2008 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

The master document, of which this is a chapter, describes the inspection of residential air conditioning systems (A/C systems) to inform home buyers, owners, and home inspectors of common cooling system defects. Asbestos in or on HVAC ducts is a possible hazard for which we provide links to a separate document - see "Asbestos HVAC Ducts" at below left.

LOCATION OF REGISTERS & DUCTS - Location of air conditioning return or supply outlets

Supply and return too close together

You don't have to be an HVAC design engineer to see that in the photograph at page top and shown again here the air conditioning supply register is above and just a few feet from the central air conditioning return grille. Cool air delivered to this attic room will mostly fall down to be simply drawn right back into the return. Poor supply and return duct locations like this can severely reduce the effectiveness of the cooling system and increase its operating costs. In this particular home the installer was confronted with a shoehorn retrofit of the air handler and duct work into a sub-standard attic bedroom closet in an area where s/he was not permitted to open cathedral ceilings nor to construct a delivery duct along the ceiling or under the floors. It was a costly to operate and poor performing air conditioning installation.

Location of Heating or Cooling Return Registers in Basements

The photograph shows a basement door into which an installer cut two return air inlets to feed basement air back to an air return located at the basement air handler. As we discussed at INCREASING RETURN AIR, this is a poor design that increases heating or cooling system operating costs. In addition to that issue, placement of return air inlets in basements, depending on their location, risk other potential hazards including: Carbon monoxide hazards: Return air registers too close to oil or gas fired equipment may draw combustion gases or carbon monoxide into the air duct system, sending dangerous gases into the living space Carbon monoxide production may be increased and heating fuel combustion incomplete at nearby heaters, water heaters, or even gas clothes dryers, if the air handler is pulling return air from a confined space where combustion equipment is also located. Air-starved equipment may not only work improperly, but may be unsafe, producing dangerous carbon monoxide. We've also found this problem in basements where the owner, attempting to improve basement air quality, ran powerful exhaust fans continuously. Placement of Air Returns at Outside Walls Heating or cooling return air duct systems which place the return register at outside building walls may perform poorly. Some heating authorities opine that more effective and economical design places these registers on the interior walls - the outside walls and perimeter of some rooms may be chilly even when the heat is operating.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

Technical Reviewers

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

More Information on Building Diagnostic Inspections and Repairs

InspectAPedia ^TM Home & Site Map - Building Inspection, Diagnosis, & Repair, Environmental Inspection & Testing - Research Website

The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems

Home Inspection Construction Consulting Services & advice for home buyers

Use this simple, economical mold test kit by following our instructions on how to collect and mail mold samples to our lab

Environmental Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis, Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing removal of environmental and other hazards and prevention of their recurrence.

Contact Daniel Friedman for website content suggestions or for fee-paid consulting

	Enter your search termsSubmit search form
	Search This Website - InspectAPedia.com