What replaces R-123 in centrifugal chillers?
Need R-123 for servicing an existing chiller? We supply it in 90.8 kg drums as a registered ODS seller.
Why there is no drop-in
A centrifugal chiller is designed around one refrigerant. Impeller size and speed, heat-exchanger surface, the purge unit, seals, oil and controls are all matched to R-123's pressure and vapour density. Change the fluid and capacity and efficiency move with it, sometimes a long way. That is why every credible route out of R-123 starts with the chiller manufacturer.
Safety moves too. R-123 is class B1. A machine converted to another B1 fluid keeps the same machinery-room approach; a machine built for an A1 fluid is designed differently from the start.
The options compared
| Refrigerant | Type | Safety class | GWP | Boiling point | Where it fits |
|---|---|---|---|---|---|
| R-123 | HCFC | B1 | 77 (AR4) | 27.8 °C | Existing low-pressure chillers; being phased out |
| R-1233zd(E) | HCFO | A1 | about 1 | 18.3 °C | New low-pressure centrifugal chillers |
| R-514A | HFO-based azeotrope: HFO-1336mzz(Z) / trans-DCE, 74.7/25.3 | B1 | 2 (AR5) | 29.1 °C | New low-pressure chillers, and retrofit of some R-123 machines |
| R-1234ze(E) | HFO | A2L | under 1 | −19 °C | Newer medium-pressure centrifugal and screw chillers; not an R-123 retrofit |
R-514A's boiling point sits close to R-123's, which is why it is the fluid offered for retrofits. R-1233zd(E) boils lower, so it suits chillers designed for it. Older retrofit routes used HFC-245fa, itself a high-GWP HFC now covered by the Kigali phase-down. The US regulator also lists R-450A and R-513A for new chillers; like R-1234ze(E), they are medium-pressure fluids.
Retrofit or replace?
The decision usually turns on four things:
- Remaining life. An old machine with a poor leak record is rarely worth converting.
- Manufacturer approval. A retrofit without it risks capacity, reliability and warranty.
- Supply of R-123. In India servicing supply continues to 2040 but draws on a shrinking allowance; see Is R-123 banned in India?
- The plant room. Detection and ventilation must suit whichever fluid the machine ends up with.
What to check before deciding
Start with the nameplate: the refrigerant, the charge and the model. Ask the manufacturer whether a retrofit bulletin exists for that model, and what it changes. Check the purge unit's run history as a measure of leak tightness. Plan the recovery of the existing R-123 charge, which is a controlled substance and must not be vented. Our chiller refrigerant guide covers screw and scroll machines as well.
Quick answers
Is there a drop-in replacement for R-123?
No. Any change of refrigerant in an R-123 chiller needs the manufacturer's approval and an engineering assessment. R-514A is the fluid offered for retrofits of some R-123 machines.
What refrigerant replaces R-123 in new chillers?
New low-pressure centrifugal chillers are built for R-1233zd(E), class A1 with a GWP of about 1, or R-514A, class B1 with a GWP of 2.
Can R-1234ze replace R-123?
Not in an R-123 machine. R-1234ze(E) is a medium-pressure refrigerant used in chillers designed for it.
- US EPA · Management of HCFC-123 through the Phaseout and Beyond (2020): uses, US servicing rules, recovery and reclamation, alternatives listed for new chillers · PDF.
- Chemours · Opteon XP30 (R-514A) Product Information: composition, boiling point, AR5 GWP 2, ASHRAE class B1 · opteon.com.
- Hulse et al., “Physical Properties of HCFO-1233zd(E)”, Journal of Chemical & Engineering Data 57 (2012) · pubs.acs.org.
- IPCC Fourth Assessment Report (2007), Working Group I, Table 2.14: HCFC-123 100-year GWP 77, lifetime 1.3 years · ipcc.ch.
- Ozone Cell, MoEFCC · A Handbook for HCFC Phase-out and Energy Efficiency in Buildings: centrifugal chillers of 300 TR and above commonly use low-pressure HCFC-123.
- R-123 Safety Data Sheet (National Refrigerants): boiling point, AIHA WEEL of 50 ppm TWA, health effects and decomposition products · PDF.
This guide is general information compiled from the cited sources, not legal, safety or engineering advice. Read our full disclaimer.
Related: R-123 supply · What is R-123? · Is R-123 banned in India? · R-123 vs R-22 · Chiller refrigerants · Charging a chiller