A2L refrigerants – myths and realities

In the first of a series of articles, Karl Richardson of Logicool Air Conditioning & Heat Pumps presents an unbiased look at the myths and realities of the new “mildly flammable” A2L gases.

Having spent the best part of the last six months researching R32 and A2L refrigerants and also having successfully trained a lot of our customers on this subject I think it is time to deliver this knowledge to the general trade in the most relevant and compact way possible.

The air conditioning industry is facing a huge step-change in the next few years.

From 2015, the EU is reducing CO2 emissions that are directly produced from the manufacture of refrigerants (it seems that we have given up on trying to prevent leaks). In previous years we have seen CFCs and HCFCs banned completely. The new regulations encourage innovations by capping the potential CO2 emissions in stages between 2015 and 2030.

CO2 emissions from refrigerants are directly related to global warming potential (GWP). Every refrigerant has a GWP number. The higher the number, the higher the CO2 emissions, the more effect that any product leaked to atmosphere has on the environment.

By assembling data from all refrigerant producers, importers etc between 2009 and 2012, the EU has imposed a baseline CO2 figure of 183 million tonnes of consumption.

The refrigerant producers/importers within the EU are now issued with a CO2 emissions quota on an annual basis. They can only produce more product by encouraging the use of refrigerants with a lower GWP. They cannot manufacture more than their quota. This promotes innovation in that the EU is not restricting sales but potentially encouraging growth but only via lower-GWP product.

Phase down

Remember that the European phase-down started in 2015. This was 100% of the baseline figure. The current phase-down for 2016 is 93% of the baseline. By 2030 we need to be at 21% of the baseline. This means an 81% reduction or 34.77 million tonnes of CO² compared to the 2015 baseline of 183 million tonnes. The challenge is to engage with a growing market by producing more product but emitting less CO² to the atmosphere.

The reality is that 2014 saw a CO2 consumption figure much greater than the actual benchmark. This can be put down to potential factors such as a significant increase in imports before the benchmark began in 2015 and restored confidence in the economy.

Of greater concern are the following facts and figures:

• The economy is much more buoyant now than when the benchmark data was analysed. Therefore we are, in reality, in a much deeper phase-down if the typical market consumption is already on the increase and in excess of the predicted actual product equivalent of 183 million tonnes

• 2017 – 37% reduction (115.29 million tonnes)

• 2024 – 69% reduction (56.73 million tonnes)

Simple mathematics tells us that if we do nothing then we will have a real supply issue in 2017.

Progress

Some industries that use refrigerants are already progressing with lower GWP alternatives. One well documented example is the automotive market. This particular industry is transferring to the HFO R1234yf which has a GWP of just 4. Considering that its predecessor R134a had a GWP of 1430 this means that as a rule of thumb we can charge 1428 new cars with R1234yf to achieve the same GWP or CO2 impact as one car with R134a.

Products such as air-to-water heat pumps and chillers are also already making the leap to lower GWP alternatives, although this is not as advanced as the automotive market.

This is comforting news for other industries such as the one that I operate in. It gives us a little bit of breathing space.

Packaged air conditioning is slow to react to the required changes by way of launching product. The reasons are complex but are mainly down to re-publishing of existing legislation which I will cover in another post. However, the following are the principle reasons for the delay:

• Some EU countries currently prohibit the use of flammable refrigerants in commercial applications (Spain, Italy, France)

• Chillers, air to water and automotive systems are fixed charge, fixed capacity systems. Packaged splits and VRF have variables such as differing capacities, pipe sizes and pipe runs. This means that the design and application of the product are different and need more thought from an r&d perspective.

• The total allowable refrigerant charge will be limited in packaged air conditioning products and this is likely to affect the range of products available.

R32

Changes to legislation are not moving as quickly as we would like. However, it seems that most Japanese manufacturers have confirmed pre-2017 launches for RAC products. This means small commercial/domestic systems up to and including 7kW. Some manufacturers have confirmed packaged/commercial air conditioning products “sometime in 2017”. Expect all the main players to confirm their official announcements soon. Two of our manufacturers have commercial product (up to 14kW split systems) confirmed for 2017. At Logicool we already have R32 product installed and available in 2.5, 3.5 and 5kW flavours.

All of these packaged air conditioning products will  be charged with refrigerant R32. This is a mildly flammable refrigerant but there is no need to panic.

In the UK, if you or your engineers have City & Guilds 2079 and/or a valid F-Gas certificate then you are qualified to use A2L refrigerants including R32. 

The mild flammability is only an issue if you do not understand why and how. The products have a flammable logo on the nameplate so awareness and management are key to this. I will cover this in a future post.

R32 has a GWP of 675 compared to R410A which has a GWP of 2088. This means that our refrigerant suppliers can continue to supply our specific industry with refrigerant for the next few years.

What we as an industry need to do is focus more on containment and promote good practice. Keeping refrigerant where it should be is the ultimate goal. Expect more changes from 2020 onwards as R32 may not be the long-term solution for all products.

What is here to stay is A2L, all of which are mildly-flammable refrigerants. This is a culture change that we need to get to grips with now.

In Part 1, we looked at A2L refrigerants and why the air conditioning industry is faced with moving from R410A to R32.

Hopefully we now understand that this is to comply with EU requirements to reduce CO2 emissions.

Now let’s move on to the main issue with A2L Refrigerants. They are flammable. Or, to be exact, they are “mildly flammable”. But what does this mean?

I have heard some talk in the industry that “it is not really flammable and that this is much ado about nothing”. Let’s explore that and examine the facts and the reality.

In the last twenty years the world has changed. A naked flame applied to R22 with mineral oil would create a similar effect to R32 with synthetic oil. Mineral oil such as Suniso 3GS used with CFC or HCFC refrigerants is a “product not classified as flammable but is inherently combustible”

But that was then and this is now. We live in a world dominated by health and safety, legislation and regulation. Unless you are extremely fortunate you will have clients who will expect you to be aware that A2L refrigerants are flammable (albeit mildly) and that you have training, documentation and procedures to handle this fact.

During the 1970s to 1990s engineers admit that they vented refrigerants liberally and used them as cleaning agents. Leak containment was not an issue and it would not be unusual to keep topping up leaking systems with new refrigerant. These refrigerants had high GWP’s (R502 = 4657). Health and Safety was not the issue that it is now. In 1974 fatal injuries in the workplace totalled 651.

Now it is illegal to vent refrigerant to atmosphere. A young engineer accepts they would be disciplined if they did not reclaim, recover and recycle refrigerants. R32 is mildly flammable and has a GWP of 675, and we are actively pursuing lower GWP alternatives. In 2014-2015 fatal injuries in the workplace totalled 92. Health and Safety is now a real issue and anything that is potentially combustible or flammable raises eyebrows.

All A2L alternatives are mildly flammable. All new refrigerants being tested are A2L. Mild flammability is here to stay and our industry needs to adapt to working with these products.

Remember: if you have a valid F-gas certificate then you are qualified to use HFC refrigerants. R32 is an HFC. Remember that safety bit at the beginning of your training? It is now relevant.

Whilst you may assume that mildly flammable refrigerants are “not really flammable”, your client may have a different perception and they will expect you to be professional in the handling of the product.

Your client is likely to see a flammable label on the side of their unit. It will not say “mildly flammable”. All installers should be aware of this and be prepared to provide answers. “It’s not really flammable, trust me” may not placate a business owner or health and safety manager. People see what they see. A flammable label is a flammable label.

What does A2L mean?

Typical refrigerants that we use in the HVAC industry are split into three safety classifications.

A1: low toxicity, non-flammable
A2: low toxicity, lower flammability
A3: low toxicity, higher flammability

There is a proposal for a new classification to allow the industry to accommodate new lower GWP products, most of which are “A” Class refrigerants. The proposal is for “A2L” refrigerants which is lower flammability with lower flame propagation. By this we mean that any flame will have a burning velocity of less than 10cm/sec.

This reclassification is important to the future of the HVAC industry. Presently, A2 refrigerants are banned from public buildings in Spain, Italy and France. This reclassification to A2L will allow these refrigerants to be used widespread throughout Europe. However, for this to happen legislation needs to be rewritten and republished. The legislation that is affected is not just BS: EN378 but also EN60335-2.

For those who have noticed the drip-feed of R32 product into the market you will note that the largest offering is a 5kW domestic wall-mount.

It is no co-incidence that half of Western Europe will not allow R32 in public installations and commercial air conditioning product is not yet available in the UK. We all draw from similar stock and it is vitally important that legislation is rewritten and republished to allow the reclassification to A2L refrigerants. Once done we should see an influx of R32 product.

EN60335-2

Our industry is governed almost solely by BS: EN378. This governs the life cycle of an air conditioning system from initial design through to installation, servicing and end of life.

EN60335 is a piece of legislation which covers the safety of Household and Similar Electrical Appliances. Air Conditioning products are already covered by this legislation but it has never previously been an issue to the industry. However, now that we have a “flammable” refrigerant inside our pipes it becomes a significant issue which brings this legislation into play.

I will cover the implications of this when we look at design and application considerations in a future post.

Flammability

So just how flammable are A2L refrigerants? There is a lot of conjecture on this issue. Some are more flammable that others but they all have lower flammability, lower flame propagation levels.

Let’s look at R32 as our example. This is the proposed solution for commercial air conditioning.

Is it flammable? Yes

What do I need to ignite R32?
A concentration limit (or LFL) of between 13 – 30
An MIE (Minimum Ignition Energy) of 30 to 100mJ
A flame higher than 600°C
A constant supply of oxygen

Can I set fire to it? Yes

Will my engineers try to set light to it? I know of engineers who have applied a flame to leaking propane in fridge cabinets so who is to say?

Can a spark from a light switch ignite it? No

What is the most likely circumstance of a flame being produced? An engineer, most likely in error, or the product in the wrong hands.

Will this be a substantial flame requiring emergency services? Not unless you keep holding a flame to the exposed refrigerant or if it creates a fire by setting light to another material. The propagation is very low and the flame will normally self-extinguish.

Assuming all of the above, how likely is it that R32 will ignite on site? Very unlikely (and I write that so as not to implicate myself by saying “no”. But there is never a “never”)

But surely with all of the above it is possible? Yes.

What would the most likely scenario be? A system that is being installed may have a leak and an engineer from any trade may be using a constant flame in the vicinity of that leak. Poor practice may cause this but it is very unlikely. The chances of a similar set of scenarios occurring when the system is installed are equally unlikely.

So there is nothing to worry about then? If you take that approach, then you are more likely to have an incident.

What is LFL

As per the above, oxygen, MIE, a temperature of over 600°C and the concentration limit are the ingredients for combustion.

We are unlikely to exceed the MIE in an installed environment. As stated earlier, the energy from a switch should not exceed the MIE.

It is, of course, possible to apply a flame of over 600°C to a leaking system and this will create a flame. An example of this can be seen on our YouTube channel by clicking here.

The Lower Flammability Limit or LFL is essentially the minimum concentration limit that is required for the product to become potentially combustible. Anything less than the LFL means that combustion is not possible.

LFL can be presented as a number or in volume. Examples for R32 are 0.307 or 13.3%.

There is also an Upper Flammability Limit or UFL. Any concentration greater than this means that the product mix with oxygen is too rich and therefore the product cannot combust.

So how likely is it to exceed the LFL in day-to-day air conditioning applications?

For split system applications it is unlikely unless a product has been significantly oversized for the application. VRF may pose other questions due to total refrigerant charge but at present there are no VRF products on the horizon so we do not need to consider that scenario at the moment.

I will revisit this when we look at design and application. This is the one area that will need consideration as it will directly affect what products come to market and how we apply our products to comply with current and forthcoming legislation. Going forward, LFL will become an important buzzword in air conditioning design and application.

To summarise the important issue of flammability for now:
• If you are F-gas trained, then you are qualified to handle R32
• Ensure your health & safety procedures are up to date.
• Consider further training on hydrocarbons and adjust your policies and procedures to fit around the handling of those products
• Be aware that your customer may have questions that they will be seeking assurance on.
• Yes, your customer may have a gas supply but don’t use that as a lazy argument. Be knowledgeable and professional in your answers and advice.
• Respect R32 and A2L.
• Don’t cut corners. If R410A allows you to cut some corners, then stop now. R32 may not be so forgiving.