NC-2009 EAc4: Enhanced Refrigerant Management

  • NC_CS_EAc4_Type3_Refrigerant Diagram
  • Some common misconceptions

    This credit can be fairly difficult to understand at a glance. So let’s start by getting some common misconceptions out of the way.

    One common misconception is that this credit specifies or prohibits a certain refrigerant type. That was true in early versions of LEED (and is still the case in the prerequisite, EAp3). For this credit, there are both HCFCsHydrochlorofluorocarbons (HCFCs) are refrigerants that cause significantly less depletion of the stratospheric ozone layer than chlorofluorocarbons. (hydrochlorofluorocarbons) and HFCs (hydrofluorocarbonsHydrofluorocarbons (HFCs) are refrigerants that do not deplete the stratospheric ozone layer but may have high global warming potential. HFCs are not considered environmentally benign.) that may or may not meet the requirements. 

    Another misconception is that this credit solely concerns refrigerants’ ozone-depleting and global-warming potentials (ODP and GWP), and that a refrigerant like R-410A automatically complies because it has low ODP and GWP numbers. But the credit requirements also include other variables, such as the ratio of coolant charge to cooling capacity for a given compressor unit, and this credit considers the life of the unit and the refrigerant leakage rateThe speed at which an appliance loses refrigerant, measured between refrigerant charges or over 12 months, whichever is shorter. The leakage rate is expressed in terms of the percentage of the appliance's full charge that would be lost over a 12-month period if the rate stabilized. (EPA Clean Air Act, Title VI, Rule 608).. R-410A, for example, may be compliant in some scenarios but not in others. 

    Two main requirements

    To earn this credit, you’ll need to:

    • minimize refrigerant environmental impact by avoiding refrigerants entirely or using systems that reduce their harmful impacts; 
    • and not install or retain fire suppression systems with CFCs, HCFCs or halonsHalons are substances, used in fire-suppression systems and fire extinguishers, that deplete the stratospheric ozone layer.

    The credit is about reducing the environmental impact of refrigerants in HVAC&R equipment, and relates to all space conditioning and large-scale refrigeration systems in project buildings. It deals with two environmental impacts of concern: depletion of the ozone layer, and greenhouse gas emissions. EAc4 goes a step further than EAp3: Fundamental Refrigerant Management, which only sets the thresholds for ozone-depleting compounds.

    All permanently installed HVAC&R equipment with more than 0.5 lbs of refrigerant—including chillers; unitary HVAC equipment (split and packaged); room and window air-conditioners; computer, data center, and telecom room cooling units; and commercial refrigeration equipment—is addressed by this credit.

    The credit also addresses fire suppression systems that contain ozone-depleting substances, including CFCs, HCFCs, or halons. Halon production was banned in the U.S. in 1994, as it is many times more ozone-depleting than CFCs and HCFCs.

    Why it matters

    While ozone is an unwanted pollutant at ground level (it’s a key component of smog), in the upper atmosphere a sparse layer of ozone plays a critical role in filtering out harmful ultraviolet rays from sunlight.

    The Montreal Protocol on Substances that Deplete the Ozone Layer—the world’s first global environmental protection treaty—prescribed a complete phase-out of CFC-based refrigerants by 1995, and of HCFCs by 2030 in developed countries. As a result, environmentally preferable refrigerants are becoming more widely available for new systems.

    Thinking ahead to earn the credit

    From an environmental perspective, the best way to earn this credit is to avoid the use of refrigerants altogether, by using either passive or evaporative cooling strategies, or with absorption chillers (see Related Products in the right column). 

    If neither of these is an option for your project, earning this credit will be more about the selection of mechanical equipment and associated refrigerants. 

    The best way to determine credit compliance is to run compliance calculations as soon as an HVAC system is proposed. Not all compressor units have to be in compliance individually; this credit calculation uses a weighted average based on cooling capacity (in gross ARI-rated ton). Leakage rates and coolant charge are as important as GWP and ODP factors in influencing credit calculations.

    If your project already has designed an HVAC system and now wants to change the refrigerant to meet the credit, you will find that it may not be as simple as swapping out the coolant or the compressor unit for a more environmentally benign choice. Rather, your entire HVAC system may have to be resized to accommodate the different capacities and efficiencies of the newer units.

    A centralized plant helps

    This is a relatively easy credit to obtain if your project has a centralized cooling plant, with a favorable “coolant charge to cooling capacity” ratio. But even for projects with smaller, more dispersed units, this credit should be achievable if you consider the credit requirements early.

    Ironically, some of the refrigerants that can help earn this credit are used in systems with poorer energy efficiency, resulting in increased greenhouse gas emissions. (CFCs were super-efficient, they just happened to be toxic and destroyed the ozone layer.) The life cycle of operational efficiency and refrigerant performance is not covered by this credit, but leakage and direct environmental impact are. Any loss of efficiency is a trade-off that has to be accounted for in EAc1.

    FAQs for EAc4

    Where can refrigerant equipment rates be obtained for equipment?

    Per LEED InterpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. #1540 issued 9/11/2006 and rescinded on 4/30/2009, NC-v2.2 projects registered after April 30, 2009 must use default values for leakage rates. All NC-2009 projects must use default values for leakage rates.

    In the past the use of non-default leakage rates were acceptable provided that documentation was provided. Has that changed?

    Yes, USGBC is no longer accepting non-default leakage rates.

    Which portions of a VRF/VRV system should be considered for this credit?

    The system capacity should be based on the outdoor units, while all parts of the system including outdoor, indoor units, branch selectors and piping should be counted for the total refrigerant charge.

    Should all commercial refrigerant equipment be accounted for, including both upright and under-counter?

    Any piece of equipment containing greater than 0.5 lbs. of refrigerant should be included in calculations.

    For a split system, does the cooling capacity refer to the cooling power of the interior device (evaporator) or of the outdoor unit (condenser)?

    The system capacity should be based on the outdoor units. If you have multiple interior devices connected to one outdoor unit, the cooling capacity should be for the outdoor unit, but the refrigerant charge must include all interior devices.

    What is the required timeline for completing a CFC phaseout for EAc4?

    While a phase-out is allowed in the prerequisite, EAc4 is like other credits where the credit should be achieved as part of the LEED scope of work. The work should be completed during construction.

    How can I document a longer equipment life (20 or 30 years) than what is listed in the LEED Reference Guide?

    The project team must use equipment life values from the 2007 ASHRAE Applications Handbook as listed in the LEED Reference Guide. For equipment not listed in the ASHRAE Applications Handbook, an assumed equipment life of 15 years must be used. An alternative equipment life may only be used if supporting documentation can be provided justifying the value. As stated in the LEED Reference Guide, acceptable supporting documentation includes a manufacturer’s guarantee and equivalent long-term service contract. An estimated equipment life is not allowed.

    Do the requirements apply to portable fire extinguishers or only permanently installed building-wide fire suppression systems?

    Portable fire extinguishers are not required to be included in EAp3 or EAc4.

Legend

  • Best Practices
  • Gotcha
  • Action Steps
  • Cost Tip

Pre-Design

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  • Consider Option 1


  • If your project has no cooling system or uses a system without refrigerants, you can achieve the credit through Option 1 (“do not use refrigerants”). Document your credit compliance path with appropriate supporting documents by completing the credit form and providing cut sheets or other confirmation of the system type.


  • Earning EAp2 and drawing up energy efficiency goals can help to determine your project’s cooling strategy as it relates to energy consumption. This exercise may help you prioritize energy performance versus refrigerant selection, when applicable.


  • If your building uses only natural ventilation, it complies with Option 1 and the credit is automatically earned without your having to submit any calculations.


  • Option 2 


  • To comply with Option 2, you’ll need to calculate the weighted impact of the following characteristics of all refrigerants used in your project: 

    • environmental impact (through destruction of the ozone layer and the concentration of greenhouse gases in the atmosphere);
    • coolant capacity and refrigerant charge (determined by equipment specs); 
    • rate of refrigerant leakage (determined by equipment life);
    • and end-of-life refrigerant loss (largely determined by equipment specs).

  • The calculated weighted average for the project should not exceed 100: 

    (LCGWP + LCODP x 105 ≤  100). See the credit language and LEED Online for additional detail on the formulas behind that calculation.

     


  • All permanently installed HVAC&R equipment with more than 0.5 lbs of refrigerant—including chillers; unitary HVAC equipment (split and packaged); room and window air-conditioners; computer, data center, and telecom room cooling units; and commercial refrigeration equipment—is addressed by this credit. 


  • Any fire suppression systems must contain no halons, CFCs, or HCFCs. This requirement is separate from the refrigerant requirements and is not included in refrigerant compliance calculations.


  • EPA’s SNAP program (see Resources) lists a range of alternatives to ODP substances. Review these alternatives and confirm the applicability to your system type. Consider using these to help meet the credit requirements. 


  • Identify suitable systems in collaboration with the project owner and facilities management. Common alternatives for fire suppression systems usually are based on carbon dioxide, water, or dry chemicals (ABC or BC type powders). 


  • If your project building is connected to a district chilled-water system, you have to include all the chillers in that system in the calculations, even if they are outside your project’s scope or control. 


  • Even one piece of equipment can tip your calculations to compliance or noncompliance. Use the calculator in the LEED Online credit form to run calculations from the beginning of HVAC system selection (note that your project has to be registered through LEED Online to download those forms). This gives a sense of how far from compliance a system may be; teams then get a better idea of how significant a change may be required. Note that annual leakage and end-of-life refrigerant loss rates are set to defaults but can be edited if needed. 

Schematic Design

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  • Consider incorporating passive cooling strategies in your design to reduce or eliminate the need for mechanical equipment that uses refrigerant.


  • Your mechanical engineer can investigate alternative mechanical systems that use natural refrigerants such as water, carbon dioxide, or ammonia. 


  • There may be first-cost and operating-cost differentials for alternative refrigerants, so careful research is required. 


  • Operations and maintenance staff need to be on board if you select a system that is unconventional or requires a new maintenance protocol. It is best to have operations and maintenance staff participate in MEP meetings regardless of system type. 


  • Check the table of commonly used refrigerants in the LEED Reference Guide. Identify those that have lower values of ozone-depleting or global-warming potential (ODP or GWP, respectively).


  • Consult equipment cut sheets for refrigerant name and capacity, leakage rate, and end-of-life loss—or call the manufacturer directly for this information. A higher leakage rate implies a higher environmental impact as well as a higher recharging cost for the project. 


  • R-410A is a common replacement for R-22 as it is more environmentally benign, with similar performance. It can help with compliance, depending on the equipment variables of “coolant charge to cooling capacity” ratio. 


  • Because mechanical conditioning and ventilation represents a large portion of your building’s energy use, equipment—and consequently refrigerant—selection will affect your energy consumption and costs. 

Design Development

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  • System choice is crucial to earning this credit. Centralized systems are likely to be more efficient and to make compliance easier. Equipment for decentralized systems has been slower to convert to more benign refrigerants, so compliance can be more difficult. 


  • Check multiple equipment manufacturers to see what refrigerants they specify for their equipment. There may be a variety of system types that will help meet the credit requirements in a variety of ways. 


  • Packaged terminal air conditioners (PTACs) typically use refrigerants with a high environmental impact. These units may make meeting the credit requirements more challenging, especially for hotels and multifamily residential projects, which tend to use them. The industry has been moving toward upgrading these refrigerants, so check with manufacturers for recent upgrades to their products. Newer refrigerants may help credit calculations. 


  • Common split systems use varying refrigerants, in a range of quantities and leakage rates. These systems can have a hard time meeting the threshold for credit compliance because their leakage rates are high. Check your specifications early in the design stage and investigate these products if you’re thinking of using split systems. 


  • The default leakage rate used in the credit form calculator is 2%, and the end-of-life refrigerant loss value should be 10%. If your project has equipment with different leakage rates, those values can be used instead. 


  • There are trade-offs with all refrigerants. R-410A, for example, has a lower refrigerant charge, defined as the ratio of refrigerant to gross cooling capacity, but it uses more energy which may increase operating energy costs and will have a negative impact on your compliance with EAc1: Optimize Energy Performance, and total energy use reduction for the project. 


  • All refrigerants involve tradeoffs. HFCs, for example, don’t contain chlorine and have zero ozone depletion potential, but they have significant global warming impact. HFCs are also less efficient than conventional, chlorine-based refrigerants, which are the most damaging to the ozone layer. Ammonia is highly efficient and ozone safe, but it can be hazardous to human health if released in large quantities.


  • Note that this credit requires the weighted average of all refrigerants to be less than 100, even if, individually, some are higher. That’s why it’s important to run the calculations several times until the final equipment is selected for your project. 

Construction Documents

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  • Complete credit calculations based on the finalized mechanical system design.


  • The refrigerant charge is typically calculated automatically in the LEED Online credit form. It is the relationship between how much refrigerant is needed (in pounds) and the cooling capacity (in gross ARI-rated tons) of the equipment.


  • Specifying high-quality equipment with a long lifespan can reduce environmental impacts, since most leakage occurs during installation and decommissioning. For information about the service life of different types of HVAC equipment, refer to the 2007 ASHRAE Applications Handbook—HVAC Applications. (See Resources.) 

Construction

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  • Complete your documentation on LEED Online. Input the product make and model. If not using the defaults provided by LEED Online, input the refrigerant charge, leakage rate, and end-of-life leakage based on the equipment data.


  • Organize documentation of equipment specs and the maintenance requirements intended to minimize refrigerant leakage and transfer this information to the owner’s facility managers.


  • Retain the manufacturer’s cut sheets showing the leakage rate of each piece of equipment. 


  • Provide refrigerant leak-detection equipment in the same location as your HVAC&R equipment. 


  • Put in place a program of preventive maintenance for the equipment end-of-life management.  


  • Retain manufacturers’ data and design specifications for your fire suppression system, confirming that it meets the credit requirements. 

Operations & Maintenance

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  • Refrigerants are not harmful to the atmosphere until they are released into it. Comply with best-practice refrigerant management regulations to minimize leakage rates during operation and when installing or removing new equipment. 

  • USGBC

    Excerpted from LEED 2009 for New Construction and Major Renovations

    EA Credit 4: Enhanced refrigerant management

    2 Points

    Intent

    To reduce ozone depletion and support early compliance with the Montreal Protocol while minimizing direct contributions to climate change1. Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). (U.S. Environmental Protection Agency, 2008) 2.The increase in global average temperatures being caused by a buildup of CO2 and other greenhouse gases in the atmosphere. This temperature change is leading to changes in circulation patterns in the air and in the oceans, which are affecting climates differently in different places. Among the predicted effects are a significant cooling in Western Europe due to changes in the jet stream, and rising sea levels due to the melting of polar ice and glaciers..

    Requirements

    Option 1

    Do not use refrigerants.

    OR

    Option 2

    Select refrigerants and heating, ventilating, air conditioning and refrigeration (HVAC&R) that minimize or eliminate the emission of compounds that contribute to ozone depletion and global climate change1. Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). (U.S. Environmental Protection Agency, 2008) 2.The increase in global average temperatures being caused by a buildup of CO2 and other greenhouse gases in the atmosphere. This temperature change is leading to changes in circulation patterns in the air and in the oceans, which are affecting climates differently in different places. Among the predicted effects are a significant cooling in Western Europe due to changes in the jet stream, and rising sea levels due to the melting of polar ice and glaciers.. The base building HVAC&R equipment must comply with the following formula, which sets a maximum threshold for the combined contributions to ozone depletion and global warming potential:

    LCGWP + LCODP x

    105

    100



    Calculation definitions for LCGWP + LCODP x 105 ≤ 100
    LCODP = [ODPr x (Lr x Life +Mr) x Rc]/Life
    LCGWP = [GWPr x (Lr x Life +Mr) x Rc]/Life
    LCODP: Lifecycle Ozone Depletion Potential (lbCFC11/Ton-Year)
    LCGWP: Lifecycle Direct Global Warming Potential (lbCO2/Ton-Year)
    GWPr: Global Warming Potential of Refrigerant (0 to 12,000 lbCO2/lbr)
    ODPr: Ozone Depletion Potential of Refrigerant (0 to 0.2 lbCFC11/lbr)
    Lr: Refrigerant Leakage RateThe speed at which an appliance loses refrigerant, measured between refrigerant charges or over 12 months, whichever is shorter. The leakage rate is expressed in terms of the percentage of the appliance's full charge that would be lost over a 12-month period if the rate stabilized. (EPA Clean Air Act, Title VI, Rule 608). (0.5% to 2.0%; default of 2% unless otherwise demonstrated)
    Mr: End-of-life Refrigerant Loss (2% to 10%; default of 10% unless otherwise demonstrated)
    Rc: Refrigerant Charge (0.5 to 5.0 lbs of refrigerant per ton of gross ARI rated cooling capacity)

    Life: Equipment Life (10 years; default based on equipment type, unless otherwise demonstrated)



    For multiple types of equipment, a weighted average of all base building HVAC&R equipment must be calculated using the following formula:

    ( LCGWP + LCODP x 105 ) x

    Qunit

    ≤ 100
    ——————————————————————————————

    Qtotal




    Calculation definitions for [ ∑ (LCGWP + LCODP x 105) x Qunit ] / Qtotal ≤ 100
    Qunit = Gross ARI rated cooling capacity of an individual HVAC or refrigeration unit (tons)
    Qtotal = Total gross ARI rated cooling capacity of all HVAC or refrigeration


    Small HVAC units (defined as containing less than 0.5 pounds of refrigerant) and other equipment, such as standard refrigerators, small water coolers and any other cooling equipmentThe equipment used for cooling room air in a building for human comfort. that contains less than 0.5 pounds of refrigerant, are not considered part of the base building system and are not subject to the requirements of this credit.

    Do not operate or install fire suppression systems that contain ozone-depleting substances such as CFCsChlorofluorocarbons (CFCs) are a compound of carbon, hydrogen, chlorine and fluorine, once commonly used in refrigeration, that depletes the stratospheric ozone layer., hydrochlorofluorocarbons (HCFCsHydrochlorofluorocarbons (HCFCs) are refrigerants that cause significantly less depletion of the stratospheric ozone layer than chlorofluorocarbons.) or halonsHalons are substances, used in fire-suppression systems and fire extinguishers, that deplete the stratospheric ozone layer..



    Potential Technologies & Strategies

    Design and operate the facility without mechanical cooling and refrigeration equipment. Where mechanical cooling is used, utilize base building HVAC&R systems for the refrigeration cycle that minimize direct impact on ozone depletion and global climate change1. Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). (U.S. Environmental Protection Agency, 2008) 2.The increase in global average temperatures being caused by a buildup of CO2 and other greenhouse gases in the atmosphere. This temperature change is leading to changes in circulation patterns in the air and in the oceans, which are affecting climates differently in different places. Among the predicted effects are a significant cooling in Western Europe due to changes in the jet stream, and rising sea levels due to the melting of polar ice and glaciers.. Select HVAC&R equipment with reduced refrigerant charge and increased equipment life. Maintain equipment to prevent leakage of refrigerant to the atmosphere. Use fire suppression systems that do not contain HCFCsHydrochlorofluorocarbons (HCFCs) are refrigerants that cause significantly less depletion of the stratospheric ozone layer than chlorofluorocarbons. or halonsHalons are substances, used in fire-suppression systems and fire extinguishers, that deplete the stratospheric ozone layer..

Organizations

US EPA Significant new alternative policy

Program to evaluate and regulate substitutes for the ozone-depleting chemicals that are being phased out under the Clean Air Act.

Technical Guides

2007 ASHRAE Applications Handbook – HVAC Applications

To determine the service life of a piece of HVAC equipment.


Treatment of Distric or Campus Thermal Energy in LEED v2 and LEED 2009 (Updated August 13, 2010)

Required reference document for DES systems in LEED energy credits.

Web Tools

Atmospheric Life of Refrigerants

The table ranks commonly used refrigerants based on their life in the atmosphere. Longer-lived compounds typically have higher global warming potential (GWP).

Publications

Green Fire suppression technologies

Article describing the movement towards Halon free chemicals with a comparative analysis.


Greenhouse Effect

Greenhouse Effect explained and illustrated.

Articles

Good Ozone, Bad Ozone

Article explaining the ozone layer problem.

Refrigerant Management Calculator

Use this refrigerant management calculator to track and document your compliance with EAp3 and EAc4. You may also use the LEED Online credit form to document compliance, but that form has a finite number of rows, whereas this one can be expanded indefinitely. If you choose to use this calculator, add a narrative in LEED Online about using a supplemental calculator to complete calculations, and upload the document on LEED Online.

LEED Online Forms: NC-2009 EA

The following links take you to the public, informational versions of the dynamic LEED Online forms for each NC-2009 EA credit. You'll need to fill out the live versions of these forms on LEED Online for each credit you hope to earn.

Version 4 forms (newest):

Version 3 forms:

These links are posted by LEEDuser with USGBC's permission. USGBC has certain usage restrictsions for these forms; for more information, visit LEED Online and click "Sample Forms Download."

Design Submittal

PencilDocumentation for this credit can be part of a Design Phase submittal.

102 Comments

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. Feb 18 2012 LEEDuser Moderator

James, I agree that this is a factor.

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James Keohane, PE LEED BD+C CxA CPMP Sustainability and Commissioning Consultant, Sustainable Engineering Concepts, LLC Feb 19 2012 LEEDuser Member 669 Thumbs Up

A followup to my original question. I have found at least one major manufacturer (T) that was able to meet BOTH IPLV - 0.36 AND have a calulated EA credit 4 of less than 100. So it is possible, I just needed to apply a little more pressure to Mfr. Rep. Maybe someday the Chiller Mfrs. will open up their chiller selection software so that Engineers can make optimized chiller selections to meet each projects needs. A guy could dream!!!........

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Rebekah Burke Director of Sustainable Design Clark Nexsen
Sep 19 2011
LEEDuser Member
436 Thumbs Up

Tonnage Associated with Energy Recovery Equipment

Is the tonnage requirement for the credit supposed to include compressor capacity only or can additional capacity from energy recovery devices be included in the tonnage?

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. Nov 19 2011 LEEDuser Moderator

Rebekah, I believe tonnage would include the whole system capacity.

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Lauren Sparandara Sustainability Manager Google
May 06 2011
LEEDuser Expert
15423 Thumbs Up

Central Plant Question

Scenario: Campus new construction projects which are connecting to an existing central plant for heating and cooling. The reference guide and DES guideline are clear that you must consider the refrigerant in the central plant (or District Energy System) when doing the calculation. One of the variables in the EAc4 calculation is service Life of equipment. These values are provided for new equipment by the ref guide and ASHRAE.

Question: For the existing central plant equipment, should the service life be the full rated service life as published by ASHRAE or a prorated life accounting for the current age of the equipment (since it is not new)?

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Lauren Sparandara Sustainability Manager, Google May 11 2011 LEEDuser Expert 15423 Thumbs Up

The GBCI responded to my question and said that I should use the Reference Guide and ASHRAE values and not the actual age of the equipment. Wanted to share this information with everyone.

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Devani PERERA Green Building Consultant ELAN
Apr 27 2011
LEEDuser Member
246 Thumbs Up

Gross ARI rated cooling capacity

Hi,
Where should I get the "gross ARI rated cooling capacity" for air to water heat pumps ? This is not covered by ARI 550/590 which usually applies to chillers. On the technical data sheets, I found the "nominal cooling capaciy" following Eurovent standard.
Do you think I can use this value ?
Thanks
Aurélie

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Christopher Schaffner Principal & Founder, The Green Engineer, LLP Nov 28 2011 LEEDuser Expert 7400 Thumbs Up

I think the nominal cooling capacity is close enough for this calculation.

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Christopher Schaffner Principal & Founder The Green Engineer, LLP
Apr 19 2011
LEEDuser Expert
7400 Thumbs Up

Heat Pipes

Here's a stumper for y'all.

A "heat pipe" uses refrigerant migration (without compressors) between two coils for heat recovery. If I am using a heat pipe system, do I include that refrigerant charge in my calc for EAc4? If I do, how do I determine the tonnage?

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Bill Swanson PE, LEED AP, Integrated Architecture Apr 19 2011 LEEDuser Expert 15040 Thumbs Up

There doesn't seem to be a lot of practical, usable numbers available for this technology. I'll let anyone else jump in here, I have no experience with heat pipe.

I'd say if the refrigerant is part of the HVAC&R equipment then it should be included in the credit calc. I see one company uses de-ionized water.

Regarding tonnage, I thought this was a load calculation based on climate, internal loads, and building envelople. A ton of cooling is equal to a ton of cooling, regardless of the equipment doing it. If a room needs 10 tons of cooling then that's the size of the heat pipe system specified.

The type of heat pipe, ambient temp, and orientation will affect how much energy it can transfer. I think it's up to the manufacturer to tell you a tonnage. And you may need to do a watts to ton conversion.

Interesting links I found. Now I know a little more about heat pipes.
http://www.enertron-inc.com/enertron-resources/library.php
http://www.fsec.ucf.edu/en/publications/pdf/FSEC-FS-27-84.pdf

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Ted van der Linden Director of Sustainability DPR Construction
Mar 07 2011
LEEDuser Member
105 Thumbs Up

FM-200 (HFC-227ea) as Clean Agent Fire Suppression

Clean agent fire suppressant materials have no bearing on the Life Cycle Ozone Depletion calculation as they are not used as refrigerants. However, there is a statement in the Enhanced Refrigeration Management document from the LEED Reference Guide that in order to achieve the credit, fire suppression systems must avoid the use of halonsHalons are substances, used in fire-suppression systems and fire extinguishers, that deplete the stratospheric ozone layer., CFCsChlorofluorocarbons (CFCs) are a compound of carbon, hydrogen, chlorine and fluorine, once commonly used in refrigeration, that depletes the stratospheric ozone layer., and HCFCsHydrochlorofluorocarbons (HCFCs) are refrigerants that cause significantly less depletion of the stratospheric ozone layer than chlorofluorocarbons..

Our project, a massive Mission Critical Facility, is currently planning on using FM-200 (HFC-227ea) which is a heptafluoropropane, and not listed as a Halon, CFC or HCFC.

Has this Clean Agent Fire Suppression been approved for usage and do you anticipate any problems in our approach in utilizing it?

The reference product (HFC-227ea) does have a Global Warming Potential of GWP=3,660, but likely unrelated to his decision.

Any help would be awesome!

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Ben Stanley Sustainability Manager, YRG sustainability Mar 16 2011 LEEDuser Expert 4458 Thumbs Up

Hi Ted,
It's a good question and though specific fire suppression systems don't go through a pre-approval process for LEED, the system is compliant by virtue of being an HFC rather than HCFC, CFC or Halon. That is the critical piece for this credit. Also, this data sheet http://www.fike.com/pub/fpsdocs/c.1.07.01.pdf notes that it's a good replacement or halon systems.

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Nena Elise
Feb 23 2011
LEEDuser Member
3395 Thumbs Up

I still don't understand how

I still don't understand how I am supposed to find out or calcuate int Rc? Is this a number you get from the manufacturer? Which in my case is Panasonic and I doubt I will be able to get a hold them. Any help?!!

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Ben Stanley Sustainability Manager, YRG sustainability Mar 16 2011 LEEDuser Expert 4458 Thumbs Up

Nena,
Can you get the cooling capacity (in tons) and the total pounds of refrigerant in a full charge (lbs of refrigerant) for the equipment from manufacturer cut sheets, technical information documentation, or the company website? Refrigerant charge is calculated by dividing the total pounds of refrigerant in a full charge by the cooling capacity of the equipment. So the resulting value is in units of lbs/ton.

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Shirley Siu Sep 28 2011 LEEDuser Member 30 Thumbs Up

Is the original charge in manufacturer's spec the same as full charge? I can only find the original charge.

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Christopher Schaffner Principal & Founder, The Green Engineer, LLP Nov 28 2011 LEEDuser Expert 7400 Thumbs Up

Yes.

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Abdulrahman Sherazy LEED AP bd+c - Projects and Environment Manager, L'OREAL Cosmetics Industry LCI Feb 25 2013 Guest 611 Thumbs Up

The cooling capacity of the split units in our project is calculated according to ISO not ARI standard. Can I use it ?

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Werner Sobek WSGreenTechnologies GmbH
Feb 04 2011
LEEDuser Member
179 Thumbs Up

SF6 in MV switchgears - Any LEED limits?

Does the SF6 (Sulphur Hexafluoride) insulating gas used to quench the arc in electrical power equipment (MV switchgears) need to be taken into consideration under the EAc4? The credit language states that only the refrigerants in HVAC&R equipment are considered in the calculation. Nonetheless, I just wanted to confirm this as SF6 is a greenhouse gas which has a very large GWP. From my review, there do not seem to be any other LEED credits that would limit the use of SF6. Does anyone know anything to the contrary? Thanks!

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. Feb 04 2011 LEEDuser Moderator

Lara, there is a bit more too this credit. It also prohibits fire suppression systems using CFCsChlorofluorocarbons (CFCs) are a compound of carbon, hydrogen, chlorine and fluorine, once commonly used in refrigeration, that depletes the stratospheric ozone layer., hydrochlorofluorocarbons (HCFCsHydrochlorofluorocarbons (HCFCs) are refrigerants that cause significantly less depletion of the stratospheric ozone layer than chlorofluorocarbons.) or halonsHalons are substances, used in fire-suppression systems and fire extinguishers, that deplete the stratospheric ozone layer.. If SF6 is considered to be one of these, then using it counts here. If not, then I'd say it's not considered for this  credit, despite its high GWP.

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Veronika Sundberg Environmental Engineer - Certification, Skanska Sverige AB Jan 16 2012 LEEDuser Member 1416 Thumbs Up

Is the LEED requirement for HVAC&R equipment OR for any refrigerant that creates HVAC&R for the buildings users? A product that is used for cooling the equipment (not get to warm for example as the one mentioned above) but it is NOT used in any equipment that creates HVAC&R for the building (air conditioner, freezer or comparable). Should that refrigerant be included or not? I do believe so, but please advise.

Thank you!

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. Feb 18 2012 LEEDuser Moderator

Veronika, the scope of the credit is defined in the credit language above. It's not a simple yes/no answer to your question. Among other things, fire suppression systems are considered.

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Kenneth Lynch
Jun 09 2010
LEEDuser Member
116 Thumbs Up

Refrigerant Charge

I'm confused about the Refrigerant Charge as a requirement for this credit. The language of the LEED 2009 manual in the "Select Equipment with Efficient Refrigerant Charge" paragraph under Implementation would suggest that Charge values MUST comply with Table 2 in that same section. However, there is no mention of Refrigerant Charge, other than its definition as it applies to the Impact Formula, in the Credit Requirements.

Further more, if you look closely at Sample Calculation 2 for the Office Building, the Rc values for the pony chiller and AC unites are way above what is allowed by Table 2. Yet, it still says the credit is awarded because the Average Refrigerant Environmental Impact is less than 100.

I'm inclined to think that, as long as my impact calculation comes out to be less than 100, I should be OK even if some of my equipment exceeds the max Rc. Can anyone confirm or refute this for sure?

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Shillpa Singh Senior Sustainability Manager, YR&G Jun 14 2010 LEEDuser Member 1673 Thumbs Up

Kenneth
It looks like Table 2 is an example of maximum refrigerant charge for a single equipment with some assumptions and default leak rate of 2%, and end of year loss of 10%. If you find the equipment installed on your project has lower refrigerant charge, please use the actual number in the calculation. The credit is awarded if the Average Atmosphere Refrigerant Impact is less than 100. It would be very helpful to support all calculations and refrigerant charges with manufacturer data and cut sheets

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gustavo goldman
May 03 2010
Guest
222 Thumbs Up

refrigerant R417 A

Is this possible, to use R417 A in replacement for the R22?
Does it comply with EAC4? I don't see it as a possible refrigerant in the list provided by LEED.
Thanks

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. May 03 2010 LEEDuser Moderator

My understanding is that R417A is a blend of refrigerants, and that it seems likely to be in the class of refrigerants that can be helpful for earning this credit.

It's important to note that EAc4 does not specifically ban or allow any specific refrigerants. Credit compliance depends on a calculation. The list you're referring to seems like it may just be a reference list of common refrigerants that appears in the LEED Reference Guide.

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Omar Katanani
Apr 15 2010
LEEDuser Member
7861 Thumbs Up

Will R134a, R407c and R410a always comply ?

Hello,

I realize that there is a calculation methodology outlined in the LEED Guidance in order to determine whether or not refrigerants comply.

However, this methodology assumes that the amount of each refrigerant type (in tons) is known. What if we do not have this figure yet?

Can we simply say that R134a, R407c and R410a comply no matter their quantity since each of them has a Refrigerant Atmospheric Impact <100 ?

Many thanks for the help.

George

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. Apr 15 2010 LEEDuser Moderator

I wouldn't be able to tell you offhand whether those refrigerants would be compliant in all typical scenarios.

However, I would emphasiz that compliance with this credit is highly dependent on the calculation that includes the refrigerent charge, so I would caution you from making any assumptions without doing at least a rough estimate of the charge.

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Nena Elise Sep 01 2010 LEEDuser Member 3395 Thumbs Up

How does one estimate the refrigerent charge? Is this something you get from the manufacturer of the unit?

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Tristan Roberts LEED AP BD+C, Editorial Director – LEEDuser, BuildingGreen, Inc. Sep 02 2010 LEEDuser Moderator

Nelina, this question is answered in the Checklists tab above in the Construction Documents section. A number of other helpful tips are also provided there. (This content is reserved for members.)

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Jason Franken Sustainability Professional Sep 08 2010 LEEDuser Expert 7203 Thumbs Up

No, the refrigerant will not always comply because the credit calculations consider the sum of the equipment leakage rateThe speed at which an appliance loses refrigerant, measured between refrigerant charges or over 12 months, whichever is shorter. The leakage rate is expressed in terms of the percentage of the appliance's full charge that would be lost over a 12-month period if the rate stabilized. (EPA Clean Air Act, Title VI, Rule 608). and refrigerant charge, as well as the GHG potential and ODP potential of the refrigerant. It's best to track down each of the required data points (with the help of an 3rd-party expert if necessary) and complete the calculations; GBCI will definitely require this to comply with the credit requirements.

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Jim Chaters sales manager, Mitsair Apr 11 2013 Guest 4 Thumbs Up

I have read all thes threads and some of them touch on my question.
#1Where should I get the "gross ARI rated cooling capacity" for air to water heat pumps ?
This is not covered by ARI 550/590 which usually applies to chillers. The issue is if we use chiller numbers we are using lower numbers as we need more refrigerangt for the heat pump so our refrigerant per ton is higher even though the heating side of the heat pump has great efficiency and the chiller side or a chiller in general is not very efficeient. It seems like efficiency is being penalised. Is there a way around this as our number is too high fro the credit

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Ante Vulin Sustainability Manager, YR&G Apr 15 2013 LEEDuser Expert 1127 Thumbs Up

If there is not an ARI standard for your equipment, I would suggest using the standard referenced by the manufacturer (such as EN14511) to determine capacity. Also, energy efficiency of systems is rewarded under other LEED credits. The purpose of this credit is to reward efficient use of refrigerants. Heat pumpA type of heating and/or cooling equipment that draws heat into a building from outside and, during the cooling season, ejects heat from the building to the outside. Heat pumps are vapor-compression refrigeration systems whose indoor/outdoor coils are used reversibly as condensers or evaporators, depending on the need for heating or cooling. In the 2003 CBECS, specific information was collected on whether the heat pump system was a packaged unit, residential-type split system, or individual room heat pump, and whether the heat pump was air source, ground source, or water source. systems may or may not be able to comply, depending on configuration.

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