4/11/09Sustainable Bulding Advisor1 Vince Cord Poly-Tech Environmental Inc.

4/11/09Sustainable Bulding Advisor2 Eight Considerations for a Green and Healthy HVAC System 1.Energy efficient design 2. Safe materials 3.Duct and equipment sealing 4.Air filtration 5.Outside air (central ventilation) 6.Adequate returns 7.Cleanliness 8.Fiberglass insulation in the air stream

4/11/09Sustainable Bulding Advisor3 1. Energy Efficient System Design

4/11/09Sustainable Bulding Advisor4 Attic Split System

4/11/09Sustainable Bulding Advisor5 Basement Split System

4/11/09Sustainable Bulding Advisor6  For proper operation and maximum energy efficiency, residential systems should be designed according to the highest industry standards:  Manual J, Residential Load Calculation.  Manual D, Residential Duct Systems.  Manual J and D are written by ACCA (Air Conditioning Contractors of America)

4/11/09Sustainable Bulding Advisor7 2.Non-Toxic Materials All materials and equipment used in this presentation have been independently tested to contain no toxic substances. If you choose to use other materials you will be risking the introduction of unhealthy chemicals/substances into the living space.

4/11/09Sustainable Bulding Advisor8 Safe duct sealants: Dow Corning 999A clear; ( Design Polymerics; DP1010; DP1020 (

4/11/09Sustainable Bulding Advisor9 Reflective Insulation (a.k.a. bubble wrap) or foil faced FSK duct wrap, to keep fiberglass particles contained. Available at local HVAC supplier.

4/11/09Sustainable Bulding Advisor10 3.Duct and Equipment Sealing.  Every visible seam and joint must be meticulously sealed in order to ensure a tight duct system.  Follow all CEC title 24 guidelines, even if the project is in an exempt costal area (  Seal your system to leak less than 5% of rated system air flow. Includes new and existing buildings.  Have your fully assembled system (including heating and cooling equipment) tested by a qualified duct tester (aka cheers rater). See for a list of raters in your area.

4/11/09Sustainable Bulding Advisor11 Avoid open return-air passages

4/11/09Sustainable Bulding Advisor12 Open return, properly sealed

4/11/09Sustainable Bulding Advisor13 Seal all penetrations into air- handling equipment

4/11/09Sustainable Bulding Advisor14 Seal all electrical penetrations into air-handling equipment

4/11/09Sustainable Bulding Advisor15 Typical leaks around start-collar Notice light from other side

4/11/09Sustainable Bulding Advisor16 Properly sealed start-collar

4/11/09Sustainable Bulding Advisor17 Properly sealed register boot in ceiling. This is one of the worst areas of leakage on just about every system.

4/11/09Sustainable Bulding Advisor18 Properly taped furnace blower access door, tape all four sides

4/11/09Sustainable Bulding Advisor19 Dirty blower compartment from leaks, filter bypass, and poor filter

4/11/09Sustainable Bulding Advisor20 4. Air Filtration  An often overlooked no-brainer.  Filter efficiencies are rated by MERV rating. Filter efficiencies range from 1-20 See tm. tm tm  If no MERV rating is given, it’s probably very low.  Use MERV 11 or better for primary air filtration.  Upgrade by installing an additional HEPA and Carbon bypass type air purifier.

4/11/09Sustainable Bulding Advisor21 Dirty air conditioning cooling coil

4/11/09Sustainable Bulding Advisor22 The best filter is not much good if it doesn’t fit snugly into the equipment

4/11/09Sustainable Bulding Advisor23 All factory filter retainers fall short

4/11/09Sustainable Bulding Advisor24 Popular filter with fiberglass and air bypass

4/11/09Sustainable Bulding Advisor25 Seal filter channel to duct to prevent air bypass between channel and duct.

4/11/09Sustainable Bulding Advisor26 Install Gasket in filter channel Use standard 3/8” wide x 5/16” thick foam weather stripping; available at hardware stores

4/11/09Sustainable Bulding Advisor27 4” thick, MERV 11 PowerGuard, non- fiberglass filter media(

4/11/09Sustainable Bulding Advisor28 Ultra Violet Lights  Ultra Violet lights that bathe the coiling coil in UV light are effective in preventing microbial on wet cooling coils.  UV light in the return air stream are minimally effective in killing air-borne bacteria and viruses, and may not be worth the cost.  Choose a UV light that does not emit ozone. Manufacturers will tell you that theirs do not emit ozone. Our research show that Honeywell and Second Wind coil irradiation lights do not emit ozone.

4/11/09Sustainable Bulding Advisor29 Filters should be taped into housing to eliminate leakage

4/11/09Sustainable Bulding Advisor30 After I year, with good filter system, sealed return duct and air-handler

4/11/09Sustainable Bulding Advisor31 Dirty blower compartment

4/11/09Sustainable Bulding Advisor32 5. Outside Air  Choose clean area away from crawl space or attic vents, dog runs, trash cans, dryer vents, plumbing vents, etc.  Intake should be 4’ above hardscape or 8’ above soil.  Avoid roof top air intakes because of VOC’s from roofing materials. If unavoidable intake should be at least 5’ away from roof surface.

4/11/09Sustainable Bulding Advisor33 Attic split system

4/11/09Sustainable Bulding Advisor34 Intake from crawl above hardscape

4/11/09Sustainable Bulding Advisor35 Intake from crawl above soil

4/11/09Sustainable Bulding Advisor36 Side wall intake

4/11/09Sustainable Bulding Advisor37 6. Adequate Returns Any room with a door that will ever be closed, such as bedrooms, offices, etc. (except bathrooms) must have a return duct to prevent undesirable negative pressure in the house. Any room with a door that will ever be closed, such as bedrooms, offices, etc. (except bathrooms) must have a return duct to prevent undesirable negative pressure in the house.

4/11/09Sustainable Bulding Advisor38 Attic split system

4/11/09Sustainable Bulding Advisor39 Dirty carpet at base of walls Indicates air passing through gaps

4/11/09Sustainable Bulding Advisor40 Well placed return-grilles, outside air intake and a tight duct system, will ensure that the house will have a slight positive pressure. Use an Energy Recovery Ventilator in colder climates, where neutral pressure is best.

4/11/09Sustainable Bulding Advisor41 7.Cleanliness Install clean materials. Dirty ducting and equipment contributes to poor air quality and reduces energy efficiency. Dirty ducting and equipment contributes to poor air quality and reduces energy efficiency.

4/11/09Sustainable Bulding Advisor42 Typical dirty duct

4/11/09Sustainable Bulding Advisor43 Typical leaky, return-platform

4/11/09Sustainable Bulding Advisor44 Cover open ducts during construction to keep debris out

4/11/09Sustainable Bulding Advisor45 Keep open ducts closed during installation

4/11/09Sustainable Bulding Advisor46 Keep open ducts closed during installation

4/11/09Sustainable Bulding Advisor47 Duct cleaning that works  Ducts get dirty because air filtration is poor and return-air ducts leak.  Seal all leaks in the return side of the system, including the air handling equipment.  Install a filter system with a minim um MERV 11 rating. Ensure that it will not allow dirt to bypass the filter.  A powerful dual motor HEPA filtered vacuum is connected to the main duct or plenum.  Rotation brushes on 25’ long cables are run through the ducts, by inserting it in each register boot, while others are blocked to create maximum air flow through that duct.  Follow-up with compressed air is helpful, especially on very dirty systems.

4/11/09Sustainable Bulding Advisor48  Some hand vacuuming with HEPA filtered vacuums is always needed.  Wash all registers and grilles before reinstalling.  Remove and disassemble the blower assembly for thorough cleaning.  Wash the cooling-coil and drain pan with commercial, evaporator coil cleaner. To keep VOC”S from the detergent out of the building, rinse thoroughly (even if product instructions say “no rinse”)  Be sure to tape the filter media in place and tape the blower door closed to minimize the introduction of unfiltered air.  One manufacturer of this equipment is Nikro. (nikro.com).  Air Duct Cleaning Company

4/11/09Sustainable Bulding Advisor49 8. Eliminate fiberglass insulation in the air stream.

4/11/09Sustainable Bulding Advisor50 Typical gas/electric basement split system

4/11/09Sustainable Bulding Advisor51 Fiberglass warning on typical coil-casing

4/11/09Sustainable Bulding Advisor52 Example of exposed fiberglass Note degradation

4/11/09Sustainable Bulding Advisor53 Typical roof duct liner

4/11/09Sustainable Bulding Advisor54  For new roof top ducting, use typical round insulated metal duct. Insert metal liner in straight sections and encapsulate the fiberglass in the elbows, y’s etc. with DP1010 or DP 2510 (  Existing roof top ducting may be modified to encapsulate the fiberglass liner.

4/11/09Sustainable Bulding Advisor55 Encapsulation of fiberglass on existing roof ducting using reflective insulation (aka bubble wrap), available at local HVAC distributors.

4/11/09Sustainable Bulding Advisor56 Choose HVAC units and cooling coils with foil-faced insulation (recommend American Standard or Trane)

4/11/09Sustainable Bulding Advisor57 Sealed edges of foil-faced insulation in a furnace

4/11/09Sustainable Bulding Advisor58 Most new furnaces have fiberglass in furnace blower- compartment

4/11/09Sustainable Bulding Advisor59 Blower-compartment fiberglass encapsulated

4/11/09Sustainable Bulding Advisor60 Avoid acoustic flex duct

4/11/09Sustainable Bulding Advisor61 Mylar-lined flex duct (recommend ATCO, Model #036 or 031; atcoflex.com)