Guide
Refrigerant global warming potential and the HFC phase down
Updated
Global warming potential is not an environmental footnote on a refrigeration site. It is the number that decides your gas price, your leak check interval and whether your plant has a future.
The phase down, in one line
Gov.uk states that the UK is phasing down HFCs by 79% by 2030, measured against average HFC use between 2009 and 2012, and that the phase down also applies to mixtures containing these gases (Environment Agency and Defra). Less supply of high global warming potential gas means higher prices for the gases that older plant was designed around.
Global warming potential of refrigerants you will meet
| Refrigerant | Global warming potential | Charge equal to 5 tonnes carbon dioxide equivalent |
|---|---|---|
| R404A | 3,922 | 1.3kg |
| R507A | 3,985 | Calculate from the published GWP |
| R410A | 2,088 | 2.4kg |
| R407C | 1,774 | Calculate from the published GWP |
| R134a | 1,430 | 3.5kg |
| R448A | 1,386 | Calculate from the published GWP |
| R32 | 675 | Calculate from the published GWP |
The global warming potential column is taken directly from the gov.uk F gas tables. The kilogram column is only filled in where gov.uk publishes the worked figure itself, in its leak checking guidance. For any other gas, ask your contractor to calculate and record the carbon dioxide equivalent of your actual charge rather than working from a figure copied off a web page.
What that means for old plant
- High global warming potential means short leak check intervals. The same physical charge of R404A crosses a threshold at roughly a third of the weight of R134a.
- It also means expensive top-ups. Restricted supply of the highest global warming potential gases has been pushing costs up, which turns a chronic leak into a serious operating expense.
- Conversion is a real option, not always the right one. Retrofitting a lower global warming potential blend changes capacity, oil compatibility and sometimes component selection, so it needs designing, not just decanting.
- Natural refrigerants change the compliance picture. Ammonia, CO2 and hydrocarbons sit outside the F gas leak check regime but bring their own safety duties, and CO2 systems run at pressures that raise pressure equipment questions.
There are also restrictions on using certain F gases to refill equipment, and bans on F gas in some new products. Both are published on gov.uk and both change over time: check the current guidance before committing to a refrigerant for new plant.