Refrigerant for deep freezers and ice plants
Why low temperature is a different problem
As evaporating temperature falls, the refrigerant vapour becomes less dense, so the compressor moves less mass for the same swept volume. Capacity drops and the compression ratio climbs. Push a single stage too far and discharge temperature rises to where the oil stops protecting the compressor.
That is why the equipment changes as the target temperature falls: single stage for chilled and normal freezing duty, two stage or cascade for the deep end.
R-404A and what is replacing it
R-404A became the standard for low and medium temperature commercial refrigeration because it has low glide and behaves well at low evaporating temperatures. Its problem is climate impact: a GWP of about 3,922 on IPCC AR4, the highest in common use.
Under the Kigali phase-down, quota is allocated by CO₂-equivalent rather than by tonnage, so the highest-GWP fluids consume the most quota per kilogram. That is the mechanism squeezing R-404A first, and it is a price and availability story rather than a ban.
R-448A (GWP about 1,387) is the mainstream lower-GWP route for new plant and for retrofits, with R-449A and R-452A as the other established options. None of them is a drop-in: they are zeotropic with more glide than R-404A, and they need POE oil and usually expansion valve adjustment. The R-404A retrofit guide covers the trade-offs.
Blast freezers and ice plants
Blast freezers pull product temperature down quickly and run at low evaporating temperatures under heavy load. R-404A is the common charge, with R-448A appearing on newer installations.
Ice plants split by scale. Large block-ice plants have traditionally used ammonia, and still do. Smaller tube-ice and flake-ice machines are commonly fluorocarbon, on R-404A or R-22 depending on age.
Deep freezers in retail and food service run R-404A in commercial sizes. Small sealed units, including domestic and some commercial cabinets, increasingly use R-290 propane, which is A3 flammable and factory-charged in small quantities. We do not stock R-290.
Below minus 40 °C: cascade systems
Pharmaceutical stability chambers, test chambers, ULT freezers and some process plant need temperatures a single stage cannot reach. A cascade system uses two circuits: a high stage on a conventional refrigerant rejecting heat to ambient, and a low stage on a fluid that still has usable pressure at very low temperature.
R-23 and R-508B are the low-stage fluids. Both are stocked, and the cascade guide covers where each one fits.
What we supply
R-404A, R-448A, R-23, R-508B, R-134a and R-407C, plus R-22 for servicing existing equipment. Cold-chain customers who draw the same gas on a cycle are worth telling us about, because it changes what we hold.
Quick answers
What refrigerant do deep freezers use?
Commercial deep freezers and blast freezers mainly use R-404A, with R-448A as the lower-GWP replacement on newer plant. Small sealed cabinets increasingly use R-290 propane.
What gas do ice plants run on?
Large block-ice plants traditionally use ammonia. Smaller tube-ice and flake-ice machines are commonly fluorocarbon, on R-404A or older R-22 systems.
Why is R-404A being replaced?
Its GWP of about 3,922 is the highest in common use. Kigali quota is allocated by CO2-equivalent, so high-GWP fluids consume the most quota per kilogram and tighten first.
What is used below minus 40 degrees?
A cascade system, with R-23 or R-508B in the low stage. Below roughly minus 40 degrees a single-stage fluorocarbon system runs out of usable capacity.
- IPCC Fourth Assessment Report · GWP values used across this site · ipcc.ch.
- UNEP Ozone Secretariat · Kigali Amendment HFC phase-down schedules · ozone.unep.org.
- ASHRAE Standard 34 · safety classification and blend designation · ashrae.org.
This guide is general information compiled from the cited sources — not legal, safety or engineering advice. Read our full disclaimer.
Related: Cold storage refrigerant choice · R-404A retrofit options · Cascade systems · Dairy and frozen food