Senior Technical Director

I wonder if my HVAC systems meet the requirements of the various global clean air acts?

If your system uses R22 as the refrigerant, the answer is no. The equipment will be old and inefficient and R22 was globally legislated out in 2010 due to the above clean air acts and was to be completely phased out by 2020.

R22 is a Hydrochlorofluorocarbon (HCFC) and has been identified as having high ozone depreciating potential (ODP) and high global warming potential (GWP). 1Kg of R22 has a GWP 2,090 greater than 1kg of Carbon and has an atmospheric life of 15 years so its immediate removal is advised.

If you look at the graph below it is no surprise, why action has been taken.

If your equipment is more than 15 years old and uses R410A you should consider replacing the equipment on an efficiency and environmental basis as soon as possible. R410a is a HFC and is only marginally less environmentally damaging than R22. R410A is being phased down and will be phased out of new equipment by 2030. R410A has zero ODP but has high GWP which is 2,088 greater than 1kg of Carbon and has an atmospheric Life of 16 years.

R134a is another HFC and is less environmentally damaging than R410A. SNAP and F-gas legislation has already agreed to stop the use of R134a in chillers from 2024. 1Kg of R134a has a GWP 1,300 greater than 1kg of Carbon and has an atmospheric Life of 16 years.

Government Legislation

Change is already here – CFC’s and HCFC’s are effectively already banned – HFC’s global warming potentials (GWP’s) will be phased down by 85% by 2047. Such legislation includes.

  • F-gas regulations in Europe.
  • EPA SNAP (Significant New Alternatives) Policy Program in the USA.
  • Canada HFC activities.
  • California actions.

Phase down will be done on a GWP weighted basis. Eliminating higher GWP HFCs such as R410A (GWP=2088) will have more of an impact than reductions in R134a (GWP=1300) R32 is another HFC and is less environmentally damaging than all previous CFC, HCFC and HFC refrigerants and will be the manufacturers common replacement for R410a and R134a with zero ODP & a low GWP.

1Kg of R32 has a GWP 677 greater than 1kg of carbon with an atmospheric life of 4.9 years.
What to Use Today?

R410A and R134a is still used in new chiller equipment today mainly due to equipment design. This is the case until they are legislated out of new equipment.

At that time, R32 and R454B will probably be the best alternatives to R410A and R134a, respectively.

  • HVAC Systems with R12 or R22 must be replaced.
  • Any R410A systems coming towards end of life – Consider replacement.
  • Use R32, R454B (and upcoming blends such as ) for new equipment.
Refrigerant Efficiency

Question – Should I use the lowest GWP fluid?

Contribution to global warming is based on refrigerant (Direct Effect) and equipment efficiency (Indirect Effect)

  • A low GWP fluid doesn’t help if there is an efficiency trade-off.

  • Majority of climate impact from chillers is power generation for electricity use.

  • So, a lower GWP refrigerant with lower efficiency could create more global warming
Answer – It very much depends on Equipment Type and Age – Seek Expert Advice

Many schools face financial challenges and often don’t have the necessary finances to consider overhauling their HVAC assets despite understanding the benefits it would bring, both financially and environmentally. Minimise has many years’ experience in school HVAC projects and understands the commercial constraints many schools face.

Minimise can help provide both the financial tools and the technical expertise to enable these types of projects to get done, often at no cost to the school


    Meet Andy


    Senior Technical Director

    We get asked a lot of questions about the @Minimise Global approach, and when the questions are technical we always ask Andy Smith, our Senior Technology Director. Turns out, Andy has quite a bit of great information for the common energy efficiency bloke or the super technical engineer or tradesman. So we created Ask Andy. Since we made it a cute cartoon, here is a little background to make sure he truly exists in real life.

    In his words…

    Married with two grown up girls.
    Living on the north coast of Cornwall.
    Well-travelled Electrical Engineer 30+ years experience.
    Worked on both industrial and commercial energy saving projects, large and small, all over the world.
    Headed up the lighting portion of the largest zero cost energy saving project in the world.
    Product designs include three single and three phase motor controllers, variable speed drives and high output  industrial LED fixtures.

    Hobbies include restoring vintage British and Italian motorcycles, touring and Motogp.

    See, he is real!

    So anything you want to know just Ask Andy and chances are he’ll give you an answer that he ponders on a motorcycle somewhere in an English countryside. Or in the locaa pub. Cheers!