SNAP Substitutes

EPA 608 Type 1 Chapter 3 (Take the full course for free)

In this module, we will discuss how the SNAP program affects our use of refrigerants. We will also take a look at why SNAP considers a refrigerant acceptable or unacceptable and specific examples in each category. Skip to quiz!

1. SNAP Background

Recall that SNAP stands for the Significant New Alternatives Policy and it is implemented by the EPA. The SNAP program was developed to evaluate new alternatives to replace phased out refrigerant.

New alternatives that are accepted under SNAP are less harmful for the environment. These accepted refrigerants do not deplete the ozone layer and have low global warming potentials.

The SNAP program classifies a refrigerant as either:

• Acceptable,

• Unacceptable, or

• Acceptable under use conditions.

SNAP looks at the use of refrigerants in different types of appliances. For example, SNAP evaluates refrigerants for use in chillers, ice rinks, industrial AC, and many other end-uses.

For Type I, we care about the refrigerants that SNAP considers acceptable for small appliances, since that is what Type I is. So this means we will look at the substitutes SNAP considers acceptable for new household refrigerators or freezers.

Note that SNAP approves substitute refrigerants for new appliances. Manufacturers of new appliances factory charge the appliances with acceptable substitute refrigerants. This means that older appliances can still contain refrigerant that is not acceptable as a substitute under SNAP.

2. Unacceptable Substitutes

Unacceptable substitutes generally are older refrigerants or blends including older refrigerants that are harmful for the environment.

HFC blends were used in the industry as a transition away from CFCs and HCFCs. Recall that under the Kigali Amendment of the Montreal Protocol, HFC refrigerants are also being phased out because they have high global warming potentials.

Under the SNAP program, refrigerant blends containing only HFCs are generally not acceptable as of January 2021. This means you will not see HFC or HFC blends in new refrigerators but you may see them in older ones.

An example of an HFC blend is R-404a, which is a blend of:

• 44% HFC-125,

• 4% HFC-134a, and

• 52% HFC-143a

Since all three components of R-404a are HFC refrigerants, R-404a is considered an HFC blend.

This is why R-404a is designated by the SNAP program as an unacceptable substitute for use in household refrigerators and freezers. Because the EPA labels it as an unacceptable substitute, you will not see R-404a used in new household refrigerators and freezers.

As of January 20211, other unacceptable substitutes for new household refrigerators and freezers include:

• R-407c, and

• R-410a

Recall that both R-407c and R-410a are completely HFC blends. This is why the SNAP program considers them unacceptable substitutes. So we will not see either of these refrigerants in new household refrigerators and freezers.

3. Acceptable Substitutes

Acceptable substitutes are generally newer refrigerants that are:

• Non-ozone depleting, and have

• Low global warming potential.

Acceptable substitutes include:

• Hydrocarbons, and

• Certain refrigerant blends

Recall that hydrocarbons such as propane (R-290) and isobutane (R-600a) are considered natural refrigerants. They do not contain chlorine so they are non-ozone depleting. They also have a global warming potential of 3, which is very low.

For new household refrigerators and freezers, SNAP approves the use of hydrocarbons under certain use conditions. The concern with hydrocarbons is that they are highly flammable. Use conditions set by the EPA are set to deal with the risk of hydrocarbons being flammable.

The SNAP program issues the following use conditions for using hydrocarbons as a substitute:

• Maximum charge is 2 lbs,

• Permanent labels are needed, and

• Pipes and service ports need to be marked red.

Hydrocarbons are used as a substitute in new household refrigeration appliances only. They are not approved for retrofitting existing appliances because of safety concerns around their high flammability.

Refrigerant blends that are acceptable substitutes generally have much lower global warming potential than the refrigerants they are replacing.

For example, R-450a is an acceptable substitute for household refrigerators and freezers under the SNAP program. R-450a is a blend of

• 42% HFC-134a, and

• 58% HFO-1234ze.

R-450a is an alternative to R-134a. Although R-450a contains an HFC refrigerant, it is also blended with an HFO refrigerant, which gives it a lower global warming potential than R-134a. The GWP of R-450a is 547, which is a 60% reduction from the GWP of just R-134a.

4. Conclusion

To summarize, unacceptable substitutes are generally refrigerants have have high GWP like blends that are made of completely HFCs. Some refrigerant blends containing HFC refrigerants are considered acceptable because they have much lower global warming potentials than the refrigerants they are replacing.

Hydrocarbons are considered acceptable substitutes with use conditions, but existing systems cannot be retrofitted to use hydrocarbons. Equipment containing hydrocarbons must be marked with red to deal with the risk of their flammability.

Question #1: Which of the following is not true?

1. SNAP lists acceptable substitutes for phased out refrigerants for different categories of end-uses

2. SNAP is implemented by the EPA

3. Refrigerants can be classified as unacceptable under SNAP

4. None of these

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All of these are true so the correct answer is (d).

Question #2: The SNAP program could label Refrigerant A as an acceptable substitute for use in chiller but an unacceptable substitute for vending machines.

1. True

2. False

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True!

This is true. The SNAP program looks at a refrigerant’s use in a particular end-use or appliance. Just because it is considered an acceptable substitute for one appliance does not make it automatically acceptable as a substitute for all appliances.

Question #3: Do you expect to see R-22 listed as an acceptable substitute under the SNAP program?

1. Yes

2. No

Scroll down for the answer...

No! The purpose of SNAP is to replace the use of refrigerants like HCFCs which are harmful for the environment.

We do not expect CFCs, HCFCs, or HFCs to be acceptable substitutes under SNAP.

Since R-22 is an HCFC and it’s being phased out, we do not expect it to be an acceptable substitute. In fact, R-22 is what we will be replacing with the substitute refrigerants.

Question #4: Do you expect to see R-404a in household refrigerators and freezers?

1. Yes

2. No

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Yes!

Yes, we expect to see R-404a in some household refrigerators.

Recall that the SNAP rule on HFC blends is effective as of January 2021. So household refrigerators and freezers manufactured before then could still contain R-404a.

We do not expect to see R-404a in new household refrigerators or freezers.

Question #5 Do you expect to see R-407c in new household refrigerators and freezers?

1. Yes

2. No

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No!

No, we do not expect to see R-407c in new household refrigerators and freezers.

We may see them in household refrigerators or freezers that were manufactured before January 2021, which is when the SNAP rule on HFC blends became active.

Question #6 New household refrigerators and freezers can be factory charged with

1. R-600a

2. R-290

3. Both a and b

4. None of these

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Both a and b!

R-600a (isobutane) and R-290 (propane) are both hydrocarbons and are acceptable as substitutes in new household refrigerators and freezers under SNAP.

Recall that small appliances, including household refrigerators and freezers, are factory charged. This means the appliances are functioning out of the box.

So new small appliances will be factory charged with the acceptable substitutes under SNAP.

Question #7 Isobutane is

1. R-290

2. An acceptable substitute for all household refrigerators and freezers

3. An unacceptable substitute for new household refrigerators and freezers

4. An acceptable substitute for all new household refrigerators and freezers

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Isobutane is R-600a. It is considered an acceptable substitute in new household refrigerators and freezers under the SNAP program.

It is not an acceptable substitute in all new household refrigerators and freezers because that would include older appliances. They are not acceptable substitutes for used, older appliances.

Question #8 New household refrigerators and freezers containing R-290 can contain 3 lbs of refrigerant.

1. True

2. False

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False!

This is false.

R-290 is a hydrocarbon so it is subject to use conditions.

New household refrigerators and freezers containing R-290 can only contain up to 2 lbs of refrigerant.

Question #9 We can retrofit an old appliance to operate on 2 lbs of R-600a.

1. True

2. False

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False!

This is false.

R-600a is a hydrocarbon and is subject to use conditions. Under the use conditions, we cannot retrofit old appliances to operate on hydrocarbons because they are highly flammable. Any malfunction of the modified parts will be dangerous and can cause fires or explosions.

The 2 lb maximum charge applies to new appliances only.

Question #10 Only refrigerant blends without HFCs are acceptable under the SNAP program.

1. True

2. False

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False!

Refrigerant blends can contain HFC refrigerants and still be acceptable under the SNAP program. But they are not acceptable if they contain only HFC refrigerants.

R-450a, for example, is a blend of an HFC refrigerant and an HFO refrigerant. But it has 60% global warming potential than HFC-134a because of its HFO component.

R-450a is an acceptable substitute under the SNAP program.

Question #11 R-450a is an acceptable substitute for use in new household refrigerators and freezers under SNAP. This means new household refrigerators and freezers can be factory charged with R-450a.

1. True

2. False

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True!

This is true.

R-450a is an acceptable substitute.

New household refrigerators and freezers are factory charged with refrigerants that are acceptable substitutes under the SNAP program.