Phase out of HFC refrigerants - what this means for boaters

[superheat6k]

It was announced on the News yesterday that Worldwide agreement upon phase out of HFCs has been agreed at a bigwig meeting in Ruanda. But what wasn't mentioned is that the EU is already implementing its programme of phase down of HFCs.

So what are HFCs ?

These include R134a; R407C; R417A; R422D; R410A; R404A - essentially the vast majority of refrigerants in common use today. Notably not Hydrocarbon gases (HCs) - Butane R600 or Propane R290.

These are the gas compounds invented to replace the allegedly Ozone damaging CFCs - notably R12 & R22. The problem is their alleged Global Warming Potential when measured against the major culprit for Global Warming, CO2. The HFCs mentioned have a global warming impact from ~1,300 x CO2 (R134a) to over 4,500 x (R404A). The others listed lie somewhere between these two extremes.

The present phase down will see an 80% reduction in available volumes by 2030 (~based upon new HFC production & import volume in 2011), although the recent announcement may see this date brought forward. It is expected those with lowest GWP ratings will be available longer. Anything with a GWP>2500 will be banned from use in new equipment from 2020, which from the above list means R422D & R404A.

The current phase down will be implemented in a series of steps, with a small step this year followed by a significant 30% reduction in 2018.

So what will replace HFCs ?

Another group of gases are being developed to replace HFCs known as HFOs. These are already mandatory in new cars e.g. R1234YF. But they have a significant drawback inasmuch as most are flammable.

A particular issue arises for AC systems using either the common R22 replacement R407C or the higher pressure R410A, as it is unlikely replacement gases will be developed at all for R407C, and those for R410A that are in development will not be suitable for retrofit purposes due to significant risk of fire if the gas were to leak out. New equipment using such gases will need special consideration to prevent possibility of sparks, and additional ventilation provisions.

Fridges tend to use R134a, which will have low flammability replacements and anyway are mostly fully sealed units anyway. Likely replacements for R134a in fridges will be Hydrocarbon gases (HCs) such as propane and isobutane, as these are already in widespread use in domestic fridges anyway. These are explosively flammable in the correct mix with air, so must be sited in well ventilated places. Fortunately a typical fridge only holds about 1/2 a mug full of liquified HC. Retrofit with HC or even refilling would be very hazardous, so if you do suffer a leak after R134a it will be time for new equipment.

Do I need to worry now ?

No, but if you are buying new equipment you should find out what refrigerant is being used. Do not be surprised to find many suppliers completely ignorant of the HFC phase out. My work is in the main UK fridge and AC industry and we are finding it hard to keep up with developments and the available medium to longer term options for our clients.

Generally anything using an HFC other than R134a is going to become scarce within 5 years.

But if your equipment already has one of these gases, or indeed the CFC predecessors, then as long as it keeps on working you are perfectly entitled to keep on using it. The difficulty arises if a repair is required where gas is removed or has leaked out. For this reason, and particularly on extended (split) systems with the condensing unit in one place and the evaporator in another make sure thorough installation practices have been followed. Avoid any instant connectors or flared joints, instead insist upon properly brazed systems that are also pressure tested and deep evacuated prior to first charge.

This is not going to be easy for those used to using simpler to fit systems, that are pre-charged and using quick couplers.


If any one requires specific advice please feel free to PM me, where I can discuss further with you or direct you to other points of information.

 

[rubberduck]

Thanks for the post, very informative. We have air con everywhere so will be useful. Perhaps we could buy some gas in canister form while still available ?

 

[rafiki_]

Hi Trevor, excellent post. In the auto sector, probably the biggest mobile a/c industry, 1234yf is now the norm. Daimler has tried to push back, stating the flammibility issue, however, despite extensive testing, Daimler has failed to convince the regulators. In fact the flammability of 1234 yf appears to be below most fluids used under the bonnet, including the coolant. Daimler is being tested in court by the French Government, with the threat of recalling all Mercedes models built since Jan 20014 and still using the old 134a. Daimler is developing an a/c system using CO2 as the refrigerant, but this is unlikely to become viable until 2018/19. Actually CO2 could be a great refrigerant gas for boats, but it will need a bigger compressor I understand.

 

[GrahamHR]

Isn't the "olden days" refrigerant, ammonia gas still a good refrigerant as far a performance is concerned ? (it's also very cheap indeed compared to any of the "modern" refrigerants). Sure, not nice if it leaks ( but the smell at even low levels is obvious).

 

[superheat6k]

Ammonia is in widespread use for large capacity industrial refrigeration plant, such as large storage warehouses and food manufacturing plants, but due to its toxicity and reactivity with certain metals, it is not suitable for smaller systems.

I can't see Daimler getting too far with their complaint about R1234YF. As Rafiki rightly mentions there are plenty of more flammable things under the bonnet of the average car. I do not yet have any direct experience of E1234YF but we are likely to be using R1234YF or its similar blend R1234ZE soon for large capacity water chillers, but for now the stuff is ~ 5-6 times the price of R134a, so the economics have to be right also. I understood there was an issue that Daimler were unhappy they were forced to use R1234YF even when it was not commercially available in the considerable quantities they require. One car will only use a tiny amount, but if you are making millions of cars the consumption will be extensive.

CO2 has been extensively used in Supermarkets and it has the key advantage of being completely natural and part of normal air, but it is technically very difficult to use due to the immense pressure required to contain it as a useful fluid. Most Supermarkets using CO2 suffer massive losses to leaks, but these are not illegal with CO2.

 

[rafiki_]

Ammonia is in widespread use for large capacity industrial refrigeration plant, such as large storage warehouses and food manufacturing plants, but due to its toxicity and reactivity with certain metals, it is not suitable for smaller systems.

I can't see Daimler getting too far with their complaint about R1234YF. As Rafiki rightly mentions there are plenty of more flammable things under the bonnet of the average car. I do not yet have any direct experience of E1234YF but we are likely to be using R1234YF or its similar blend R1234ZE soon for large capacity water chillers, but for now the stuff is ~ 5-6 times the price of R134a, so the economics have to be right also. I understood there was an issue that Daimler were unhappy they were forced to use R1234YF even when it was not commercially available in the considerable quantities they require. One car will only use a tiny amount, but if you are making millions of cars the consumption will be extensive.

CO2 has been extensively used in Supermarkets and it has the key advantage of being completely natural and part of normal air, but it is technically very difficult to use due to the immense pressure required to contain it as a useful fluid. Most Supermarkets using CO2 suffer massive losses to leaks, but these are not illegal with CO2.

There was a supply issue a couple of years ago, Eu derogated for a year, while the new DuPont factories in China and USA came on stream at production volumes. Price is directly related to volume, so as the new gas comes on stream, its unit price is reducing,

 

[GrahamHR]

I am a sceptical about such issues, I worked in the polyurethane foam industry for 30+ years, The 50% CFC reduction target, then the switch to HCFCs and HFAs was ill directed and managed. Brominated products would have allowed better insulation at 25% of the level of CFCs. All in the past now. So called poor (!) developing countries like India and China could still use damaging technology; how stupid is that?

Much like the military being allowed to use effective fire extinguishers ( Halons) and tin based antifoulings, unlike the civilians that pay for them, basically because they are effective

There are very few new refrigerant rmolecules possible. All at high cost (i.e. high energy requirement, causing more CO2 emission)

 

[JumbleDuck]

Ammonia is in widespread use for large capacity industrial refrigeration plant, such as large storage warehouses and food manufacturing plants, but due to its toxicity and reactivity with certain metals, it is not suitable for smaller systems.

Small ammonia cycle fridges used to be quite common in camper vans and boats. I had a nice domestic Electrolux one in my house until quite recently. Lovely and quiet.

 

[superheat6k]

Small ammonia cycle fridges used to be quite common in camper vans and boats. I had a nice domestic Electrolux one in my house until quite recently. Lovely and quiet.

The ammonia units were absorption units, which operate to a different principle of natural convective flow and the natural separation and combining of different chemical compounds, of which ammonia and I think water is one, lithium bromide is another, using a heating element that can be 12v, gas flame or 240v. The heat capacity is quite low, so limited to small fridges only, or truly massive water chillers using waste process heat, often in industrial plant.