2016 ICC Annual Conference Education ProgramsKansas City, MO 1
Flammable RefrigerantsThe Evolving Impact on Codes
With appreciation to Danfoss North America and Tidwell Consulting
Today’s Goal
Explore the changing refrirgerant environment and its potential affect on codes.
Courtesy: Johnson Controls (www.johnson controls.com)
2016 ICC Annual Conference Education ProgramsKansas City, MO 2
Learning Objectives
• Identify the environmental and code issues associated with the refrigerant gas changes.
• Describe simple refrigeration physics, terminology and chemistry.
• Identify current public safety code requirements and issues.
• Identify proposed changes in refrigeration gases.
Challenge
Traditional refrigerants are being banned or phased down
Potent greenhouse gases
Both air conditioning and refrigeration
Alternatives are available, but many are flammable
Codes currently do not allow their use
2016 ICC Annual Conference Education ProgramsKansas City, MO 3
Part I:Refrigeration Concerns
Why Change?
GLOBAL WARMING POTENTIALChlorofluorocarbons (CFCs) and
Hydrochlorofluorocarbons (HCFC)
1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
GLO
BAL WARMING IN
FLUEN
CE
2016 ICC Annual Conference Education ProgramsKansas City, MO 4
Montreal Protocol
1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
GLO
BAL WARMING IN
FLUEN
CE
Phase-out Begins January 1, 1989
GLOBAL WARMING POTENTIALChlorofluorocarbons (CFCs) and
Hydrochlorofluorocarbons (HCFC)
Hydrofluorcarbons
1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
GLO
BAL WARMING IN
FLUEN
CE
Phase-out Begins January 1, 1989
GLOBAL WARMING POTENTIALHydrofluorocarbons (HFCs)
2016 ICC Annual Conference Education ProgramsKansas City, MO 5
Global Demand
Source: National Oceanic and Atmospheric Administration (NOAA)
1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
Developing World Deman
d for A/C and Refrigeration
High estimate
Low estimate
Developing Countries
Developed Countries
EU: Move down to low-GWP refrigerants
1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
GLO
BAL WARMING IN
FLUEN
CE
100%
20%
2016 ICC Annual Conference Education ProgramsKansas City, MO 6
20202017 2018 2019
US: GWP Proposed Phaseout (EPA)
Supermarkets
Remote Condensing Units
Small vending machines
Large vending machines
Standalone low temperature devices
Central air conditioners ?
Potential ICC Effects
• IBC 1006.2.2.2– Egress from refrigeration machinery rooms
• IMC Chapter 11– Mechanical Refrigeration
• IFC 606– Mechanical Refrigeration
• Equipment testing
• Emergency controls
• Treatment and flaring systems
2016 ICC Annual Conference Education ProgramsKansas City, MO 7
Part II:Refrigeration Physics
Newton’s First Law of Thermodynamics Conservation of energy: Energy cannot be created
or destroyed in chemical reaction
Refrigeration Physics
U=Q‐WWhere:
U = change in internal energyQ = heat added to the system (energy in)W = Work done by the system (energy out)
2016 ICC Annual Conference Education ProgramsKansas City, MO 8
Heat Properties
Always moves from warmer to cooler surface
Moves by radiation, convection or conduction
When a refrigerant boils it absorbs heat
When a refrigerant condenses, it releases heat
Heat by a fluid (refrigerant) ‐‐ as it changes from a liquid to a gas ‐‐ lowers the temperature of the objects around it.
.
Compressor pressurizes
refrigerant gas
Condenser, where it rejects heat to outdoors and liquefies
Moves through valves where it
expands into a gas
Draws heat from the refrigerated space
Mechanical Refrigeration Cycle
2016 ICC Annual Conference Education ProgramsKansas City, MO 9
Mechanical Refrigeration: Operating Scheme (Simplified)
Refrigerated space
Usually outdoors
Fan
Mechanical Refrigeration: Definitions
• Compressor – Mechanical equipment that raises refrigerant pressure
• Condensing Unit -- Assembly of a compressor, condenser, fan motor, controls and a mounting plate
Courtesy: Danfoss.com
Courtesy: Copeland Refrigeration Units
2016 ICC Annual Conference Education ProgramsKansas City, MO 10
Mechanical Refrigeration: Definitions
• Expansion valve -- Adjusts refrigerant flow and pressure to satisfy all load conditions.
• Refrigerant-- Liquid or gaseous cooling medium
Courtesy: Danfoss
Mechanical Refrigeration: Definitions
• CFC– Chlorofluorocarbon
• HFC -- Hydrofluorocarbon
• HCFC--Hydrochlorofluorocarbon
2016 ICC Annual Conference Education ProgramsKansas City, MO 11
Mechanical Refrigeration: Definitions
• Specific heat • Amount of heat per unit mass required to raise the
temperature by one (1) degree Celsius (1.8F). • Used to calculate capacity requirements for
refrigerating known quantities of product
• Latent heat • Amount of heat absorbed or released by a substance
undergoing a change of state (such as ice changing to water or water to steam) at constant temperature and pressure
• Occurs in evaporator and drives the cooling process
Mechanical Refrigeration: Definitions
• Azeotrope• Blend of two or more refrigerants with similar boiling
points that act as a single fluid. • May exhibit unique and unexpected properties
• Zeotrope• Mixture of two or more refrigerants with different
boiling points. • Never mixes chemically, predictable properties• Evaporates/condenses of temperature range called
“glide”
2016 ICC Annual Conference Education ProgramsKansas City, MO 12
• Refrigerant ton– A measure of cooling capacity; not refrigerant.
• The energy removal rate that will freeze one short ton of water at 0 °C (32 °F) in one day.
• Historically defined was approximately 11,958 Btu/hr(3.505 kW), and has now been conventionally redefined as exactly 12,000 Btu/hr (3.517 kW)
• One ton of refrigeration is equal to 3024 kilo-calories per hour.
– Equals 12,000 BTU/ hr divided by 2.204 (pounds per kilogram) divided by 1.8 (°C to °F).
Mechanical Refrigeration: Units
Courtesy: Livescience.com
• Most residential A/C units capacity range:
• Large industrial chiller systems up to:
Mechanical Refrigeration: Units
Tons kW Btu/hr
1 to 5 3.5‐ 17.5 12,000‐60,000
Tons kW Btu/hr
Up to 800 2,800 9,600,000
Courtesy: excaliburlpa.co.uk
Courtesy: AC2015.com
2016 ICC Annual Conference Education ProgramsKansas City, MO 13
• For code purposes, refrigerants are measured in pounds
– Unit of liquid weight
– Refrigerants typically have density >1
• Heavier than water
• Densities lessen at higher temperatures
– Based on internal volume of the refrigeration system
• Volume x liquid density at specific temperature = pounds in system
– Check the system label.
Mechanical Refrigeration: Units
Mechanical Refrigeration: Side Note
• For response purposes, refrigerants’ vapor density should be considered
• Most refrigerant leaks occur as vapor– Vapor density >1 = vapor sinks
– Vapor density < 1 = vapor rises
Courtesy: US Chemical Safety Board
2016 ICC Annual Conference Education ProgramsKansas City, MO 14
Mechanical Refrigeration: Pounds
Recharging Vessels
Courtesy: Summit Refrigerants
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Part III:Refrigerant Chemistry
Optimal Refrigerant
• Should have low boiling point and low freezing point.
• Must have low specific heat and high latent heat. – high specific heat decreases the refrigerating
effect per pound of refrigerant, and,
– high latent heat at low temperature increases the refrigerating effect per pound of refrigerant.
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Refrigerant Composition
Prefix Represents Examples
R Refrigerant R22, R134a, R717
May include:
C ChlorineRC317
Chloroheptafluorocyclobutane
B BromineR22B1
Bromodifluoromethane
F FluorineRFE‐36
Hexafluoropropane
H HydrogenR134a
1,1,2,2‐Tetrafluoroethane
C CarbonRC318
Octafluorocyclobutane
E EtherRE170
Dimethylether
Refrigerant Nomenclature
Numbering Series
Chemistry Examples
000, 100, 200 Hydrocarbon‐based HCFC‐22, HFC 134a, R290 (propane)
400 Zeotropes R‐404A
500 Azeotropes R‐507A
600 Organic R‐600a (isobutane)
1000 Unsaturated organics HFO‐1234yf*
*Will replace HFC‐134a in automobile air conditioning
2016 ICC Annual Conference Education ProgramsKansas City, MO 17
Refrigerant Nomenclature
• Legacy refrigerant numbering scheme (R-XXXX) describes chemical composition
R(efrigerant)
>Number of double carbon bonds
> Carbon atoms
> Hydrogen atoms
> Fluorine atoms
Hydrocarbons/Derivatives
RN of double carbon bonds
(Placeholder omitted when zero)
Carbon Atoms(Minus 1)
Hydrogen Atoms(Plus 1)
FluorineAtoms
(N/molecule)
R 0 1 3 4
R22: Chlorofluoromethane – CHClF2
Remaining bonds not accounted for are chlorine.
*a = Isomer stability.
R134a*: Tetrafluoroethane – CH2FCF3
RN of double carbon bonds
(Placeholder omitted when zero)
Carbon Atoms(Minus 1)
Hydrogen Atoms(Plus 1)
FluorineAtoms
(N/molecule)
R ? ? ? ?
Zero double bonds(omitted)
1‐1= 0 (omitted)
1+1 = 2 2
2016 ICC Annual Conference Education ProgramsKansas City, MO 18
Zeotropic
Zeotropic Respective refrigerant number and mass
proportions
Number designates components, but not amount (molecules) of each
Identifying number in 400 series, assigned arbitrarily (in order of approval) R407A
(R32/R125/R134a): (20/40/40)
R407B (R32/R125/R134a): (10/70/20)
R-500 Series
Two-component refrigerant mixtures a CFC and an HFC, or,
a CFC and an HCFC Exception: R-507 a mixture of two HFCs
2016 ICC Annual Conference Education ProgramsKansas City, MO 19
Organics/Inorganics
Organics: given in numerical order in 600 series R600a : Isobutane C4H10
Inorganics: assigned in 700 series by adding molecular mass to 700 R717: Ammonia NH3
ASHRAE Safety GroupsFlammability Classification
Toxicity Group
Group A Group B
Lower Toxicity Higher Toxicity
Higher Flammability A3 B3
Lower Flammability A2 B2
Low Flammability A2L B2L
No Flame Propagation A1 B1
Increasing Toxicity
Increasing Flam
mability
2016 ICC Annual Conference Education ProgramsKansas City, MO 20
ASHRAE Safety GroupsFlammability Classification
Test
At 70F and 14.7 psi Examples
A3Higher
FlammabilityLFL <0.10 kg/m3
Latent heat > 4540*
MethanePropaneButane
A2Lower
FlammabilityLFL > 0.10 kg/m3
Latent heat < 4540*HCFC-142bHFC-152b
A2LDifficult to ignite
Flame speed < 3.94”/secR-32
R1234yf
A1No Flame
PropagationNo flame propagation in air
CFC-11CFC-113R-500
* Calories per gram
ASHRAE Safety Groups
Toxicity Groups
Group A Examples Group B Examples
Lower Toxicity Higher Toxicity
No toxicity identified at concentrations ≤
400 ppm
Evidence of toxicity at concentrations
<400 ppm
A1CFC,
HCFC,B1 Seldom used
A2 R152a B2 Seldom used
A2L Most Low-GWP HFC B2L Ammonia
A3 Hydrocarbons B3 Hydrocarbons
2016 ICC Annual Conference Education ProgramsKansas City, MO 21
Classification Denomination Formula Safety Classification
Inorganics
R717 Ammonia NH3 B2
R718 Water H2O A1
Hydrocarbons
R170 Ethane CH3CH3 A3
R290 Propane CH3CH2CH3 A3
Halocarbons
R11 Trichlorofluormethane CCl3F A1
Examples
Classification Denomination Formula Safety Classification
Hydrochlorofluorocarbons
R22 Chlorodifluoromethane CHClF2 A1
Hydrofluorocarbons
R125 Pentafluorethane CHF2CF3 A1
R32 Difluoromethane CH2F2 A2L
Hydrofluorolefins
R1234ze 1,3,3,3‐Tetrafluoroproene
C3H2F4 A2L
R1234yf 2,3,3,3‐Tetrafluorpropene
C3H2F4 A2L
Examples (cont’d)
2016 ICC Annual Conference Education ProgramsKansas City, MO 22
Vessel Identification
Courtesy: RMS of Georgia
R‐12Dichlorofluoromethane
(CFC)
R‐22Chlorodifluoromethane
(HCFC)
ZeotropicR‐22/R152a/R‐124
(HCFC)
R‐11Trichlorofluoromethane
(CFC)
R‐113Trichlorotrifluoroethane
(CFC)
R‐13B1Bromotrifluoromethane
(CFC)
2016 ICC Annual Conference Education ProgramsKansas City, MO 23
Part IV: Refrigeration Codes and Standards
The Code Challenge“State and local fire and building codes are major barriers to the
broad deployment and adoption of low‐GWP refrigerants in the U.S.,
“These codes often prohibit the use of flammable or even mildly flammable refrigerants, even in very small amounts less than a typical aerosol spray can.
“Since they’re developed and mandated locally across hundreds or thousands of jurisdictions, codes are difficult to change and create an effective obstacle to manufacturers offering products with low‐GWP refrigerants that may be flammable or mildly flammable.”
John Galyen, president of Danfoss North America
2016 ICC Annual Conference Education ProgramsKansas City, MO 24
Codes and Standards
• ASHRAE 15– Safety Standard for Refrigeration
Systems
• ASHRAE 34– Designation and Classification of
Refrigerants
• IIAR (International Institute of Ammonia Refrigeration)
– ANSI/IIAR 2‐2014 American National Standard the Safe Design of Closed‐Circuit Ammonia Refrigeration Systems
– ANSI/IIAR Standard 7‐2013 Developing Operating Procedures for Closed‐Circuit Ammonia Mechanical Refrigerating Systems
Codes and Standards
2016 ICC Annual Conference Education ProgramsKansas City, MO 25
• UL 207– Standard for Refrigerant-Containing
Components and Accessories, Nonelectrical
• UL 412– Standard for Refrigeration Unit Coolers
• UL 471 – Standard for Commercial Refrigerators
and Freezers
• UL 1995 – Heating and Cooling Equipment
Codes and Standards
Machinery Rooms
Courtesy: Food Engineering Mag.com
• Construction per IBC
• Table 509– One-hour separation or A/S
• §1006.2.2– > 1,000 ft2
• Two exits or exit access
• All portions within 150 feet
• Doors swing in egress direction
– Chapter 28
2016 ICC Annual Conference Education ProgramsKansas City, MO 26
International Mechanical Code
• Chapter 11 REFRIGERATION
• Design, installation, construction and repair
• Six-step design protocol
Courtesy: Arescobuyersclub.com
Courtesy: Hussung.com
International Mechanical Code
• §1103.2 Occupancy classifications• Institutional
• Public assembly
• Residential
• Commercial
• Large mercantile (O.L. > 100)
• Industrial
• Mixed occupancies
2016 ICC Annual Conference Education ProgramsKansas City, MO 27
IMC Design Protocol
1. Refrigeration system’s classification based on likelihood leaks entering occupied area
– Low or High probability
• Low probability:
– Double‐indirect open spray
– Indirect closed
– Indirect‐vented closed
• High probability
– Direct
– Indirect open spray
System Classifications
Courtesy: resourcecompliance.com
Liquid:liquid heat exchangers
2016 ICC Annual Conference Education ProgramsKansas City, MO 28
IMC Design Protocol
2. Refrigerant classification (A1‐B3)
3. Maximum refrigerant quantity per refrigerant, system classification and occupancy
4. System enclosure requirements
5. Refrigeration and application location and installation
6. Non‐factory tested, field erected equipment and appliances
IMC System Application
• § 1104.2 Machinery rooms
• Outdoor applications
• Institutional applications
• 50% limit on refrigerants
• Industrial occupancies and refrigerated rooms
• Exceptions for manufacturing, food and beverage prep, meat cutting and storage
Courtesy: Texas Glacier.com
2016 ICC Annual Conference Education ProgramsKansas City, MO 29
IMC Machinery Rooms
• § 1105
– Design and construction
– Ventilation requirements
• Normal/emergency
• § 1106
– Continuous ventilation for NH3
– Remote emergency shutoffs
Courtesy: sirayooth.com
Refrigerant Piping §1107
• Height above floor
• Limited building envelope penetrations
• Material limits– Steel, copper, brass, aluminum
• Valve identification
Courtesy: Stellar food for Thought.net
2016 ICC Annual Conference Education ProgramsKansas City, MO 30
International Fire Code• Section 606 MECHANICAL REFRIGERATION
– Processed by PMG Code Action Committee [M] and Fire Code Action Committee
– Operational permit required §105.6.40
– IFC regulatory thresholds• Approved FD access at:
• 220 pounds of Group A1
• 30 pounds of any other group
• For emergency pressure control systems:
• 6.6 pounds flammable, toxic or highly toxic, ammonia
Courtesy: NH3plus.net
International Fire Code
• §606.4 Refrigerant change• Must meet IMC
• §606.6 Testing and recordkeeping
• Treatment and flaring systems
• Equipment in emergency refrigeration control boxes
• Fans and equipment for emergency ventilation
• Detection and alarm systems
Courtesy: Refrigeration Today.com
2016 ICC Annual Conference Education ProgramsKansas City, MO 31
International Fire Code
• §606.7 Warning signs• Suitable for refrigerant• Comply with NFPA 704
International Fire Code
• §606.8 Refrigerant detection• In machinery room• Gas concentration area
• (Remember vapor density)• Alarm at TLV‐TWA for refrigerant class from IMC
Courtesy: Emerson Climate Technologies
2016 ICC Annual Conference Education ProgramsKansas City, MO 32
International Fire Code
• System emergency controls• § 606.9 Remote controls for flammable refrigerant rooms• Break‐glass system emergency shut OFF
• Break‐glass ventilation system ON
Courtesy: resourcecompliance.com
International Fire Code
• System controls for flammable, toxic, highly toxic or ammonia
• § 606.10 Emergency pressure control system• Automatic crossover valves transfer high pressure gases to low pressure side
• Automatic compressor stop
2016 ICC Annual Conference Education ProgramsKansas City, MO 33
International Fire Code
• System controls for flammable, toxic, highly toxic or ammonia
• § 606.11 Emergency pressure control system• Treatment and flaring systems
Courtesy: Energy‐Concepts. comCourtesy: bhtank. com
Part V:Refrigerant Proposals
2016 ICC Annual Conference Education ProgramsKansas City, MO 34
GWP: Traditional Refrigerants
0
1,500
3,000
4,500
6,000
7,500
9,000
10,500
12,000
Global warming potential compared
to 1 lb
CO2
CFCs
0
1,500
3,000
4,500
6,000
7,500
9,000
10,500
12,000
Global warming potential compared
to 1 lb
CO2
Existing CFC Refrigerants
Use in new equipment obsolete
2016 ICC Annual Conference Education ProgramsKansas City, MO 35
CFCs Unacceptable for certain EPA applications
0
1,500
3,000
4,500
6,000
7,500
9,000
10,500
12,000
Global warming potential compared
to 1 lb
CO2
Unacceptable Refrigerants
What RemainsNot EPA approved for certain applications
CFCs
Global warming potential compared
to 1 lb
CO2
0
1,500
3,000
4,500
6,000
7,500
9,000
10,500
12,000
What Remains
2016 ICC Annual Conference Education ProgramsKansas City, MO 36
Industry Investment
HVACR industry spent more than $255 million in 2015 to research, develop low-Global Warming Potential and low flammability refrigerants
Courtesy: Johnson Controls. com
2016 Industry Work Plan• Codes & Standards Task
Force– Refrigerant producers
– Equipment manufacturers
– Standards developers
– Consultants
– Retailers
– Government agencies
– Non-governmental organizations
• IFC Fire CAC reviewCourtesy: PRSEngineers.com
Courtesy: PIHO Engineering.com
2016 ICC Annual Conference Education ProgramsKansas City, MO 37
• ASHRAE 15 (Safety Standard for Refrigeration)• Meets twice annually
• Subcommittees more frequently• Being re-written• Reorganization in process to make the standard more user friendly • No technical changes
• Flammability experts reviewing scientific literature and looking to plug the knowledge gaps
Where We Are Today
• Draft of A2L-related submitted for Advisory Public Review • Followed by Publication Public
Review before changes are finalized
• Pushing to complete the process in time for the 2016 edition of Standard 15
Where We Are Today
2016 ICC Annual Conference Education ProgramsKansas City, MO 38
• “It depends”• Availability of ASHRAE 15 for the next code cycle
• Group B IFC proposals now closed• Group A IBC/IMC currently voting• UMD fire test results (ASHRAE grant)• Early detection/ventilation seem to provide promise
• ISO approach
• Meanwhile per industry it’s “business as usual”• Safety standard model codes state adoption• Be prepared to accelerate the process• ICC process allows adoption and modification of standards
• This is a communication and education process – in both directions -- between industry and code and fire experts.
Where We Are Headed
• Awareness, training and education for emergency responders is essential
• New product monitoring and code changes are critical
Where We Are Headed
2016 ICC Annual Conference Education ProgramsKansas City, MO 39
Summary The world of refrigerants (residential, commercial,
refrigeration) is changing
New refrigerants are flammable (or mildly flammable)
New refrigerant safety standards are being written
Flammable refrigerants may be the only option and in a time frame shorter than will allow the building and fire codes to be implemented
The refrigerant industry is asking for help to reach out to the fire safety and code communities to get their advice and cooperation
Questions/Comments?
2016 ICC Annual Conference Education ProgramsKansas City, MO 40
Additional Resources American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) www.ashrae.org
International Institute of Refrigeration www.iifiir.org
Global Refrigerant Management Initiative Alliance for Responsible Atmospheric Policy
www.arap.org
Air‐Conditioning, Heating and Refrigeration Institute www.ahrinet.org
Brazilian Association for HVAC‐R www.abrava.com.br
Exam