New Generation Ultra Low Global Warming Potential Refrigerants

R1234 HFO Chillers


With the planned phase down of F-gases such as R134a and R410a over the next decade, Cooltherm with our manufacturing partners have developed a wide range of machines which operate on the latest ultra-green refrigerants, whose ‘Global-Warming-Potentials’ are measured in single digits rather than thousands. Key in the quest for those all important BREEAM points. 

During the development of the machines specifically developed to operate on HFO refrigerants, we have also been able to improve the coefficients of performance even further, reducing the plants running costs and carbon footprint.

With the average chiller have a predicted operating life of 15 to 20 years, it is critical to consider careful what refrigerant you opt for today to avoid the need to potential retro fitting of the plant during its life cycle.

Taking all these points into consideration not only is a HFO chiller the right environmental choice, but it also will be of financial benefit to the operator over the chiller's life.

We have full ranges of HFO chillers for the following applications.

Click on links below for technical specifications of our standard ranges


What are your compressor choices? 

With HFO R1234ze the choices of compressor are extensive in both air and water-cooled options, and include;

  • Turbocor®, Turbomiser™
  • Reciprocating
  • Screw



HFO Turbomiser


Our premium air-cooled R1234ze Turbomiser™ now offers full load (35°C Ambient) improvement in performance of 9.5% taking our typical full load EER to 3.85 on a 300kW machine. 



At the lesser capacity end of our HFO chiller range we employ robust Frascold reciprocating compressors. Frascold joined the development of R1234ze compressors from the refrigerants inception, and have now developed into a very versatile and hardy range of compressors which we have incorporated into our VHA range of chillers instead of scrolls. Geoclima have now supplied hundreds of VHA-HFO machines globally and have proved themselves to have incredible levels of reliability. 


HFO Screw

When seeking a larger capacity machine be it water-cooled, air-cooled with free-cooling or a standard air-cooled machine, Cooltherm have a full range of HFO screws available, also with variable speed inverter options, giving much improved levels of part load efficiency over standard screws while maintaining a valued engineered price point. 




R513a the cost-effective green refrigerant alternative to R134a Chillers.

R513a (or Opteon ® XP10 as it is also known) is a readily available low global warming potential refrigerant which is a direct substitute for R134a and in many applications can used as a simple replacement for retrofitting. 

Because of its very close similarities to R134a a full and wide range of R513a refrigeration and chiller plant is already available, and because of the recent HFC price increases driven by EU F-Gas legislation it is now a more cost-effective refrigerant to use in new plant designs.

What is R513a?

  • Substitute for R134a
  • Almost identical physical and thermodynamic properties to R134a
  • Performance and efficiencies closely match that of R134a
  • Azeotropic refrigerant blend containing R1234yf and R134a
  • Non-flammable with a safety classification of A1
  • For oil dependant systems R513a is fully compatible with polyolester oil
  • Low GWP of 631
  • Can be used as a retrofit or in new installations

What new equipment can I request R513a to be used within?

  • All medium temperature chiller and industial heat pump applications with the same operating temperature ranges as R134a. (Water temperatures circa -10°C to 25°C in cooling and +30°C to +55°C in heating.)





R290 - Propane Chillers


Man & Chiller

The green traditional Refrigerant

Propane R290 is a versatile green refrigerant with a Global Warming Potential of only '3'. Propane has an operational envelopment suitable for medium-low temperature refrigeration to traditional air conditioning applications, which presents R290 as a good environmentally friendly alterative to R404a in many low temperature applications.

Cooltherm and Geoclima have been providing R290 chillers for over a decade, with a proven track record for reliability and performance. R290 is a flammable refrigerant but when applied correctly using the latest technology and leak detection systems poses no more risk than a conventional refrigerant, but at a fraction of the GWP.

CoolTherm with CIBSE have developed a CPD module on the safe use of Propane (R290) in chillers, to review this CPD module please click here. 

We have full ranges of Propane (R290) chillers for the following applications.

Click on links below for technical specifications of our standard ranges

What are your compressor choices? 

With Propane R290 the choices of compressor are:

  • Reciprocating
  • Screw

With reciprocating being applied to small capacities and screw and inverter screw compressors being applied to capacity’s from 70kW up to 2mW.