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Unique Fittings & Label Colors for MVAC Refrigerants

Unique Fittings

A unique set of fittings is required for each and every refrigerant approved for use in motor vehicle air conditioning (MVAC) systems under EPA’s Significant New Alternatives Policy (SNAP). These fittings are attachment points on the car itself, on all recovery and recycling equipment, on large refrigerant containers, and taps on small cans of refrigerant and other charging equipment.

The unique set of fittings for each refrigerant prevents the accidental mixing of different refrigerants. This helps protect the purity of refrigerant in the MVAC system. An adapter may not be used to convert a fitting.

This list includes all refrigerants listed under SNAP as acceptable, subject to use conditions, for MVAC as of May 21, 2012 for which unique fittings have been established. This table does not include GHG-HP/HCFC Blend Lambda or Ikon-12/Ikon A/Blend Zeta because unique fittings have not been developed or approved for those refrigerants.

Refrigerant

High Side Service Port

Low Side Service Port

30-lb. Cylinders

Small Cans

Diameter
(inches)

Pitch 
(threads/inch)

Thread 
Direction

Diameter
(inches)

Pitch 
(threads/inch)

Thread 
Direction

Diameter
(inches)

Pitch 
(threads/inch)

Thread 
Direction

Diameter
(inches)

Pitch 
(threads/inch)

Thread 
Direction

CFC-12 
(post-1987)

6/16

24

Right

7/16

20

Right

7/16

20

Right

7/16

20

Right

HFC-134a

quick-connect

quick-connect

8/16

16 Acme

Right

8/16

16 Acme

Right

Freeze 12

7/16

14

Left

8/16

18

Right

8/16

18

Right

6/16

24

Right

Free Zone / HCFC Blend Delta

8/16

13

Right

9/16

18

Right

9/16

18

Right

6/16

24

Left

R-414B/HCFC Blend Omicron/Hot Shot

10/16

18

Left

10/16

18

Right

10/16

18

Right

5/16

24

Right

R-414A/GHG-X4/HCFC Blend Xi/McCool Chill It

.305

32

Right

.368

26

Right

.368

26

Right

14mm

1.25mm 
spacing

Left

6/16

24

Left

7/16

20

Left

GHG-X5/Autofrost X5

8/16

20

Left

9/16

18

Left

9/16

18

Left

not sold in small cans

R-406A/GHG-12/GHG-X3/McCool

.305

32

Left

.368

26

Left

.368

26

Left

8/16

20

Left

R-416A/FRIGC FR-12/HCFC Blend Beta

quick-connect, different from HFC-134a

quick-connect, different from HFC-134a

8/16

20

Left

7/16

20

Left

SP34E

7/16

14

Right

8/16

18

Left

8/16

18

Left

5/16

24

Left

R-426A 
(RS-24, new formulation)

Quick connect, different from HFC-134a and FRIGC FR-12

Quick connect, different from HFC-134a and FRIGC FR-12

Quick connect, different from HFC-134a and FRIGC FR-12

Quick connect, different from HFC-134a and FRIGC FR-12

R-420A

0.5625 (9/16)

18

Right

0.5625 (9/16)

18

Left

0.5625 (9/16)

18

Left

0.5625 (9/16)

18

Right

HFO-1234yf

Outside diameter 17 +0/-0.2mm

Outside diameter 14 +0/-0.2mm

8/16

16

Left^

Not yet developed; additional information must be submitted to EPA.*

Quick connect consistent with J639 (2011 version)

Quick connect consistent with J639 (2011 version)

Consistent with SAE J2844 (Oct 2011 version)

HFC-152a

Outside diameter 15 +0/-0.2mm +

Outside diameter 14.1 +0/-0.2mm +

not yet developed*

not yet developed*

Quick connect consistent with J639 (2011 version)

Quick connect consistent with J639 (2011 version)

R-744 (CO2)

Outside diameter 18.1 +0/-0.2 mm +

Outside diameter 16.6 +0/-0.2 mm +

20.955 +0/-0.127 mm and right-hand thread direction

Not yet developed; additional information must be submitted to EPA.*

Quick connect consistent with J639 (2011 version)

Quick connect consistent with J639 (2011 version)

*Unique fittings have not yet been developed. Additional information must be submitted to EPA and unique fittings must be approved prior to commercialization.

+HFC-152a and R-744 service fittings are provisional pending final production, commercialization and use of the refrigerant.

^This unique fitting applies to containers of HFO-1234yf for professional servicing only (77 FR 17344).

Label Colors

Historically, EPA established a specific label colors for each refrigerant as part of its SNAP approval. The table below includes only those refrigerants for which EPA required use of a specific label color as part of the listing decision. This table does not include all MVAC refrigerants, such as those for which labeling was never developed. Also, the use conditions for HFC-152a, R-744 (CO2) and HFO-1234yf require compliance with SAE J639, which specifies the markings required on labels, but not unique label colors. These refrigerants are not included in the table below and must be labeled in accordance with SAE J639.

Refrigerant

Label Color

CFC-12

White

HFC-134a

Sky Blue

Freeze 12

Yellow

Free Zone / HCFC Blend Delta

Light Green

R-414B/HCFC Blend Omicron/Hot Shot

Medium Blue

R-414/GHG-X4/HCFC Blend Xi

Red

R-406A/GHG-12/GHG-X3

Black

GHG-X5/Autofrost X5

Orange

R-416A/FRIGC FR-12/HCFC Blend Beta

Grey

SP34E

Tan

R-426A (RS-24, new formulation)

Gold

R-420A

Dark green (PMS #347)