Supporters of R744 in Mobile A/C Systems Express Problems with 1234yf Refrigerant

Supporters of R744 in Mobile A/C Systems Express Problems with 1234yf Refrigerant

The growing reluctance over 1234yf has now led its own proponents and Original Equipment Manufacturers (OEMs) to dreadfully search for a system solution that would enable the use of the refrigerant, no matter what the system cost and efficiency implications

Stronghold for 1234yf is crumbling – part I

An editorial from R744.com  

Concerns over the safety risks pertaining to the use of the latest HFC generation refrigerant has led OEMs and 1234yf proponents to discuss a secondary-loop MAC system — a solution entailing high system costs and low efficiency levels. It now turns out that the additional cost for 1234yf was never realistically evaluated.

In a February press release, the German Environment Agency (UBA) presented test findings by the German Federal Institute for Materials Research and Testing (BAM) confirming the high safety risks incurred by the use of the latest HFC generation refrigerant HFC-1234yf (or HFO-1234yf).

This was shortly after the US-based Automotive Recyclers Association (ARA) expressed their concern over the safety risks that 1234yf would pose to automotive recycling staff and the general public.

The growing reluctance over 1234yf has now led its own proponents and Original Equipment Manufacturers (OEMs) to dreadfully search for a system solution that would enable the use of the refrigerant, no matter what the system cost and efficiency implications.

Chairman Interior Climate Control Committee (ICCC) of SAE International Ward Atkinson raised the possibility of a secondary-loop system again at the ICCC meeting held during the SAE 2010 World Congress on 13-15 April 2010. In such a system type, the refrigerant circuit is confined to under-hood, so a low-global-warming flammable refrigerant can be used in a protected environment.

A secondary loop system would mitigate only part of the risk…
Indeed, introducing a secondary loop for the front-end heat exchanger would mitigate to some extent the safety risks associated with HFC-1234yf, such as the development of highly toxic hydrogen fluoride (HF) in the case where the flammable refrigerant burns after a front crash accident. Some risk would persist, however, in case of a severe crash accident destroying the refrigerant line near the compressor and exhaust pipe.

… And at what cost?
A condenser side secondary system considered by OEMs will use a more complex condenser, a refrigerant-coolant heat exchanger, an additional coolant-air side heat exchanger required together with a pump for the coolant, a fluid transfer system and an expansion vessel.

The additional system costs for the secondary condenser-side loop would amount to €100-150, much higher than the additional costs for an R744 MAC of about €20-30 assuming annual production of 1 million units. And that is on top of the cost of the 1234yf refrigerant itself, the price of which is expected to be 10 times the price for R134a.

Costs would even be higher if an OEM decides to limit the risks in the cabin of the vehicle by introducing also an evaporative-side secondary system. Different system configurations undertaken by different OEMs would lead to market division and consumer confusion with regards to safety levels.

The costs are even higher when one considers system efficiency. Efficiencies of the condenser side secondary system compared to direct R134a expansion system will be significantly reduced hence fuel consumption will be up.

Reduced efficiency of the 1234yf secondary loop MAC system would mean that indirect CO2 emissions would exceed the direct CO2 emissions saved through the use of a low-global warming potential (GWP) refrigerant.

1234yf cost was never realistically evaluated
R744 MAC technology has been sidelined for reasons of cost and efficiency. Now it turns out that, as the additional cost for 1234yf was never realistically evaluated, the opposite is true.

To read the second installment of this editorial, Stronghold for 1234yf is Crumbling — Part II, click here.

For more on the issue of using R744 in mobile air conditioning systems, visit http://www.r744.com/

You May Also Like

ISN Expands Freedom Program for Mobile Tool Dealers

ISN’s Freedom Program is designed to provide experienced, successful mobile tool dealers with support to become an independent mobile dealer and expand their growth.

Integrated Supply Network (ISN) said it has expanded its Freedom Program for mobile tool dealers.

ISN’s Freedom Program is designed to provide experienced, successful mobile tool dealers with support to become an independent mobile dealer and expand their growth. The program provides businesses with all the sales, marketing, purchasing and financial support needed to excel as an independent mobile tool dealer, according to ISN.

Brake Lathe Basics

Resurfacing drums and rotors is a machining process with its own specific guidelines.

Refrigerant Oil Has to Be Right

Oil type is just as important as oil capacity.

Three bottles of refrigerant oil
Top 5 Tools: Steve Coffell, Auto World, Hazelwood, MO

Steve Coffell, a technician at Auto World in Hazelwood, MO, says his Top 5 Favorite Tools are: Related Articles – Mayhew Introduces New 14-Piece Micro Hand Tool Set – New Small Stud Extractor Now Available from Mayhew Tools – Matco Debuts 5-Piece Purple Screwdriver Set   OTC Genisys Touch – Quick scan, bidirectional control Snap-on

Wheel Bearing Adjustment Tools & Equipment

A wheel bearing that’s out of adjustment can reduce bearing life and can affect more than just the bearing. It’s important to adjust the wheel bearing endplay to the proper specifications. If the bearing set is adjusted too loose or too tight, it can cause the bearing to fail prematurely. There are a few types of assemblies, so using correct procedures and tools will ensure a comeback-free wheel bearing installation.

Other Posts

Snap-on Continues to Offer Free Weekly Product Training Sessions

The online training and question and answer sessions are free of charge.

TechShop, ShopOwner Offer $50 For Good Guesses

Guess the Tool for a chance at cold hard cash!

TS Toolbox Guide February 2024

Here’s a look at some of the core feature and modern frills to consider when it’s time to move into a new office.

toolbox guide illustartion
Embracing Cutting-Edge Solutions the Industry has to Offer

Embracing cutting-edge solutions is strategic and imperative for technicians navigating the constantly changing landscape of automotive maintenance and repair.

Nadine Battah