Which refrigerant does your chiller run on?
Centrifugal chillers
Centrifugal machines move large volumes of refrigerant at low pressure ratios, which historically suited low-pressure fluids. The old fleet ran R-11, then R-123 as its HCFC replacement. Both are being displaced: R-11 is long gone under the Montreal Protocol and R-123 is an HCFC on the same phase-out track as R-22.
The mainstream modern centrifugal refrigerant is R-134a. On newer low-GWP machines you will find R-1234ze, an HFO with a GWP under 1, and R-1233zd on some low-pressure designs.
We stock R-134a and R-1234ze. We do not stock R-123 or R-1233zd. If your machine runs one of those, we will say so rather than offer a substitute, because there is no substitute that goes into a centrifugal machine safely without an engineering assessment.
Screw and scroll chillers
These are the machines most Hyderabad buildings actually have: air-cooled or water-cooled packages serving an office, a hospital, a hotel or a pharmaceutical block.
R-134a is common on water-cooled screw plant. R-410A appears on scroll packages and smaller air-cooled units. R-407C turns up both as an original charge and as the retrofit that took an R-22 machine forward, because it is the closest capacity match to R-22 of the mainstream blends.
R-22 is still running in a large installed base. That is lawful to service, and we supply R-22 for servicing existing equipment under our ODS registration. What is no longer lawful is building new equipment with it, which ended on 1 January 2025.
Blends need liquid charging
R-407C is zeotropic, with a temperature glide of several degrees. Its three components boil at different temperatures, so a vapour charge changes the composition of what is left in the cylinder and what enters the machine. Charge liquid. If a zeotropic system has leaked badly, the remaining charge is no longer the specified mixture and the correct move is to recover, evacuate and weigh in a fresh charge rather than topping up.
R-410A is near-azeotropic and R-134a is a single component, so the discipline varies, but liquid charging is the safe habit across the blends.
Ammonia and the industrial end
Large industrial refrigeration, including many ice plants and cold stores, runs on ammonia (R-717). Ammonia is efficient and has no ozone or meaningful warming impact, but it is toxic and classified B2L, and it is a different supply chain with its own licensing. We do not supply ammonia.
What we can supply
R-134a, R-410A, R-407C, R-32 and R-1234ze, plus R-22 for servicing existing equipment. For a chiller recharge, the quantity is usually large enough to be worth confirming against stock before you commit to a shutdown date.
Quick answers
What refrigerant do centrifugal chillers use?
Commonly R-134a, with R-1234ze on newer low-GWP machines. Older units ran R-11 and then R-123. We stock R-134a and R-1234ze but not R-123 or R-1233zd.
What gas does a screw chiller take?
Usually R-134a on water-cooled machines, or R-410A and R-407C depending on the design. Older units run R-22. The nameplate is the reliable answer.
Can I top up a chiller running R-407C?
Only with liquid charging, and only if the loss is small. R-407C is zeotropic, so after a significant leak the remaining charge is no longer the specified mixture and should be recovered and replaced.
Do you supply ammonia for industrial plant?
No. Ammonia is a different supply chain with its own licensing and handling requirements. We supply fluorocarbon refrigerants.
- ASHRAE Standard 34 · safety classification, including B2L for ammonia · ashrae.org.
- Ozone Cell, MoEFCC · HCFC phase-out management plan · ozonecell.nic.in.
- UNEP Ozone Secretariat · Montreal Protocol control schedules · ozone.unep.org.
This guide is general information compiled from the cited sources — not legal, safety or engineering advice. Read our full disclaimer.
Related: Charging a chiller · R-134a supply · Zeotropic vs azeotropic · Hotels and hospitals