Author: Gerson Mora

The Chiller R-1234ze(E) is the most efficient alternative to chillers that work with R-134a. R1234ze (E) is one of the most promising HFO options in chillers, with a GWP of 4 and lower flammability than R1234yf.

What should you know about R-1234ze(E) in chillers?

• R1234ze (E) is commonly a component of new low GWP blends.
• The flammability of R1234ze (E) is not critical in heat pump systems in normal operation, and in low humidity it becomes non-flammable.
• The heat transfer coefficient of the evaporator with R1234ze (E) obtained in different geometries appears to be similar to the transfer coefficient of R134a.
• The heat transfer coefficient in the condenser with R1234ze (E) is 10% lower compared to R134a.
• R1234ze (E) pressure drops are always higher compared to R134a and should be considered in Exchanger Optimization.
• If R1234ze (E) is used in R134a systems, some modifications must be made to maintain energy efficiency.
• The use of R1234ze (E) in heat pumps works well, however in this case, its isomer, R1234ze (Z) is more recommended.
• HFO / HFC blends are the HFC replacements requiring the fewest system changes of all the low GWP alternatives.
• Currently, blends of R1234ze (E) are used to replace R134a, R404A and R410A in chillers.
• These mixtures have good energy efficiency and adaptation to existing legislation.

Where to learn all about chillers?

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The Chiller R-514A is offered as an option for some new centrifugal chillers and replacement for existing chillers.

R-514A is a mixture composed of 74.7% of R-1336mzz (Z) and 25.3% of R-1130 (E)).

What should you know about R-514A in chillers?

• The chemical stability of R-514A and R-1233zd (E) refrigerants has been shown to be better than R-123, and both refrigerants have been qualified for application in a range of centrifugal compressor-based chillers.
• The R514A is an upgrade alternative to the R-123, although the cooler will have to undergo some modifications.
• R-514A is a compatible design replacement for R-123 in both engineering modification applications and new production.
• Although not flammable, R514A is slightly toxic. Like R-123, R-514A has an ASHRAE B designation due to its increased toxicity

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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The Chiller R-450A is a replacement alternative to R-134a in industrial chillers and for room conditioning.

What should you know about R-450A in chillers?

• R-450A is a quasi-azeotropic blend of the hydrofluorolefin (HFO) family to replace R-134a in refrigeration and heat pump applications.
• It is made up of 42% R134a and 58% R1234ze (E), it is not flammable, it has a zero ODP and a GWP of approximately 601.
• Its performance capabilities are slightly lower than R-134a. R-450A is safe, non-flammable with low slip values.
• The R134a retrofit does not require the replacement of any system component, lubricant, or seal.
• R-450A combines HFC and HFO components resulting in a lower GWP than other HFC products.
• When modernizing the R134a equipment, a possible reduction in capacity will result in longer run times.
• Use a polyol ester oil (POE).

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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The CO2 Chiller System is a very attractive ecological alternative, which today can be used anywhere in the world.

How does the Chiller work with CO2? Subcritical?

The critical point It is the maximum value of temperature, where CO2 can change state, for example from gaseous to liquid phase.

A Subcritical cycle is one that in any state always works below the critical point.

The CO2 cycle is used within a facility with two cascade systems.

The CO2 circuit works at a low temperature and is responsible for cooling the liquid, and another cycle is used to achieve condensation of the CO2 Cycle.

The CO2 in the chiller is always below the critical point.

Transcritical CO2 Cycle Chiller:

The fundamental idea of ​​is the use only of CO2 in the entire installation, so as not to have problems with environmental regulations.

Features of the CO2 Chiller:

• The CO2 chiller works with very high pressures.
• The application of the CO2 chiller has a great future when we think about the environment.
• The Glycol Transcritical CO2 Chiller offers high efficiency and reliability for low temperature cooling.
• As the temperatures reached at the compressor discharge of a CO2 chiller are high, heat recovery can be used for other applications. With heat recovery, in CO2 chillers, water temperatures for other processes of up to 75 ° C can easily be reached.
• The CO2 Chiller is perfectly suited to a wide range of glycol supply temperatures, ranging from -30 ° C to + 12 ° C.
• The transcritical CO2 chiller is used with a flooded evaporator to cool CaCl2, ammonia-water and other industrial brines.
• There are liquid ammonia / carbon dioxide (CO2) chillers, designed for installations that require cold storage or freezer.
• The use of ammonia / CO2 chillers reduces the ammonia load by up to 90% compared to ammonia-only systems.
• Due to the high pressure value, they increase the leakage potential in the chiller with co2.
• The CO2 chiller uses specially designed components.
• Chiller compressors that work with CO2 are special due to their greater cooling capacity.
• The costs of chillers with CO2 and installation are higher either in cascade or transcritical.
• Chiller tubing that works with CO2 includes steel or stainless steel.
• Usually in CO2 chillers, stainless steel pipes are used for all cold pipes.
• Mild steel pipes are used for discharge or hot pipes.
• The components of the CO2 chiller have different joining techniques, due to higher pressure values ​​and different materials.
• Two-stage compression is required for transcritical chillers.
• Inter-stage cooling is essential in very low temperature applications, due to the high discharge temperature of R744.
• Chillers with CO2 need a purity of R744 close to 99.99%
• The wall thickness of tubes and exchangers needs to be increased to handle the higher pressures.
• CO2 refrigerant offers greater cooling capacity than most synthetic refrigerants.
• CO2 chiller needs fewer grams of refrigerant to cool the same amount of water.
• CO2 has low pressure drops, in pipes and heat exchangers favoring C O P.
• The CO2 Chiller has high heat transfer in evaporators and condensers due to the high pressure and density of the refrigerant. Although a CO2 chiller handles very high pressures, the compression ratios are lower.
• CO2 is not corrosive to most materials.
• CO2 chiller with oil has good miscibility with the lubricant.
• Polyol ester lubricants can continue to be used.
• Low toxicity and non-flammable.
• A Refrigerant Charge from a CO2 chiller is cheap.
• The CO2 molecule is stable, which leads to a low potential for decomposition within the refrigeration system.
• They are modern, fully automated equipment.
• Investing in a CO2 chiller eliminates future environmental risk and safety restrictions.
• Financial savings are substantial and generated over the life of the equipment.
• Significant reduction in greenhouse gases. Precise temperature control.
• They are highly reliable systems. Very low maintenance cost.
• Almost total elimination of the risk of ignition and toxicology, which can occur with other refrigerants in another process.
• Many of these machines are currently manufactured to run without oil to maximize efficiency.
• These equipments have less volume, occupying less space in the machine room.
• They have minimal noise levels.
• As they are modern equipment, the use of scroll compressors with a fixed capacity, or with a highly efficient inverter variator, is common.
• Electronic expansion valves help this equipment meet the latest energy requirements.
• Intermediate discharge valves, built into scroll compressors in many of this equipment, and variable speed fans improve efficiency, at part load values.
• CO2 is classified as an A1 refrigerant under ASHRAE Standard 34, which means it is non-toxic and non-flammable.
• A large confined space leak can displace oxygen for breathing. In the presence of atmospheric pressure, CO2 can change to a solid phase, it can occur when opening an overpressure relief valve, for example, the R744 outlet can be blocked by itself.

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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The Chiller R-1233zd(E) is an alternative to newer low pressure centrifugal chillers, although it is not an upgrade alternative to existing R-123 chillers.

R-1233zd (E) is a single component refrigerant that has low toxicity, is non-flammable, and also has a low GWP.

What should you know about R-1233zd (E) in chillers?

• Interestingly, 1233zd (E) is itself an HCFC, so it contains chlorine that depletes the ozone layer, but falls outside the Montreal Protocol phase-out of these gases.
• HFO R1233zd (E), a non-toxic and non-flammable alternative, has already been accepted as a suitable replacement for adoption in new equipment.
• The efficiency levels of R1233zd (E) are slightly better than HCFC-123 when used in centrifugal chillers.
• R1233zd (E) is a non-flammable refrigerant and has a GWP of only 1. Trane was the first to adopt R1233zd (E) as a new gas in a range of CenTraVac chillers introduced in 2014.
• The Channel Tunnel, 50.5 km long, consists of three tunnels. The tunnels should cool down due to the heat generated by the trains The system was upgraded with four new chillers with, R1233zd (E), each with 2,000 tons of cooling capacity.
• These centrifugal chillers were among the first to be designed for use with R1233zd (AND).

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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Chiller R-513A is currently considered as an alternative for the replacement of R-134a in existing water chillers.

What should you know about R-513A as a replacement in chillers? R-

• R513A is an azeotropic mixture of R134a (44%) and HFO-1234yf (56%).
• R-513A is a non-flammable refrigerant that has a lower GWP than R-134a, but similar performance.
• The mixture has low toxicity and flammability, along with a 56 percent reduction in GWP.
• R-513A has a GWP of 629, but as a weak point with slightly lower efficiency than R-134a.
• R-513A is a “Drop-in” direct replacement for R-134a in existing high and medium temperature commercial and industrial refrigeration equipment.
• The R-513A is presented as an excellent alternative in chillers in centrifugal and screw compressors.
• R-513A is a low GWP, non-flammable (A1) alternative refrigerant to R-134a that enables chiller manufacturers to comply with future HFC regulations.
• All Danfoss Turbocor series compressors produced as of December 2017 are compatible with R-134a and R-513A.
• By providing efficient R-134a chillers that are future compatible with R-513A, the long-term investment customers make in their chillers is protected.
• YORK Company’s chiller offering of R-134a products that can be used with R513A provides peace of mind.
• Carrier has announced that its AquaEdge 19XR and 23XR and AquaForce 30XV / XA chillers are compatible with R513A refrigerant.
• The higher vapor density of R513A on the suction side of the compressor results in a higher mass flow rate.
• When using R513A the mass flow rate increases about 15%.
• Depending on the diameter of the pipes, a higher mass flow causes a significant increase in the pressure drop in some pipes, and an increase in the compression ratio of the compressor.
• R513A is not flammable in air under normal conditions.
• R513A is also known under its trade name Opteon XP10.
• R513A is compatible with the equipment, components, lubricant and gaskets of an existing R-134a installation.
• R513A is compatible with synthetic POE oils.
• R-513A is a substance with very little toxicity.
• R-513A vapors are heavier than air and tend to collect near the ground.
• Very high atmospheric concentrations of R-513A can produce anesthetic effects and suffocation. High exposures can cause abnormal heart rhythm.

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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The Chiller R-454B is an excellent alternative both for new equipment and for the reconversion of chillers that work with R410a that use scroll compressor.

What should be known before a conversion or purchase of Chillers with R-454B?

• R-454B is a mixture of R32 and R1234yf.
• R454b refrigerant offers approximately 3% less capacity, but has the benefit of a GWP value as low as 467, making it a potentially long-term solution.
• R454B has slightly lower capacity than R410A but better efficiency. Chillers with R452B are best suited for hot climates.
• Many chiller factories have announced that they are manufacturing scroll compressor coolers. with R-454B. Many R-454B air-cooled chillers are now available in capacities from low refrigeration tons to 100-ton equipment.
• R-454B refrigerant is an HFO / HFC blend that does not deplete the ozone layer, it has a GWP level of 467, the lowest among refrigerants currently available for scroll compressor technology.

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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The chiller with R-452B is an ecological alternative with excellent performance. It is used for the replacement of R-410A and the acquisition of new equipment.

R452b is a zeotropic HFO / HFC blend classified as a mildly flammable refrigerant (A2L ASHRAE safety class) that offers an optimal balance of performance, safety and compatibility as a replacement for R410A.

What should you know before chilling with R-452B?

• R410A consists of a mixture of R32 + R125 in a 50/50 ratio.
• R452B consists of the same chemicals as R410A, with a 26% increase in R1234yf. R32: 67% and R125: 7%.
• The R452B has almost the same capacity as the R410A, with slightly better efficiency.
• R454-B is an environmentally friendly alternative to R410a gas with a GWP value of 675.
• The discharge temperature of R-452B is much lower than that of R32.
• The discharge temperature of R-452B is very close to R410A.
• R452B has a lower mass flow rate than R410A. R452 generates a lower pressure drop in pipes compared to R-410A.
• The R454B offers slightly less capacity, but has the benefit of an even lower GWP.
• In terms of capacity and efficiency, R452b is the direct replacement for R410a.
• The r452b provides excellent performance under elevated ambient conditions for air-cooled chillers.
• R452b leaks just barely reach the flammable limit. R452B has a lower heat of ignition, this factor hinders its use in larger equipment.
• The reconversion of R-410A by R452B. works with COP values ​​that are 0% to 5% higher.
• The refrigerant charge with R452B is about 10% less than with R410A.
• It has a low temperature glide.
• The energy efficiency of chillers running on R452b increases by 3.2%, while the capacity is reduced by only 1.7% with the refrigerant mass flow of 80%, compared to R410a.

Where to learn all about chillers?

We have prepared a complete training in chilled water installations with chillers.

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The ammonia water chiller is an energy-efficient machine that excels in handling large thermal loads without environmental restrictions, as it utilizes a natural refrigerant.

How does the Ammonia Chiller System operate?

Ammonia chiller systems can operate with two types of cycles:

1. Ammonia chiller working with a compression refrigeration circuit.
2. Absorption chiller utilizing ammonia as the refrigerant.

• Ammonia is an excellent option for industrial refrigeration as it does not harm the ozone layer or contribute to the greenhouse effect.
• In chillers with high thermal loads, ammonia significantly reduces electricity consumption, making it a cost-effective choice compared to other synthetic refrigerants.
• Additionally, ammonia is approximately 1.7 times lighter than air, enabling it to rise easily and form a cloud when in the presence of humid air.
• Chiller installations working with ammonia are designed to detect leaks through security systems.
• Ammonia leaks can often be detected by the human nose before becoming hazardous.
• To prevent corrosion and leakage issues, ammonia chillers are constructed using robust steel or stainless steel materials, which can influence the initial cost of the equipment.
• Ammonia chillers typically have zero overheating due to their use of flooded-type evaporators.
• They also offer the possibility of total or partial heat recovery, further enhancing the energy efficiency of the installation.
• These chillers often require less than 500 grams of ammonia per ton of refrigeration and are usually compact, assembled by the same machine manufacturers, and utilize various condensation methods, such as water, air, or evaporative.
• For chillers produced in Northern Europe, R-717 (ammonia) is commonly used.
• Specific engine rooms for ammonia chillers require dedicated mechanical ventilation systems, and ammonia leak detectors are set to values lower than established limits for safety purposes.
• Ammonia is only flammable in the presence of a high source of ignition, and explosions can occur in flammable mixtures in confined spaces, provided that the ignition temperature exceeds 635°C.
• However, in open spaces, ammonia rises and dissolves in the atmosphere, eliminating the risk of ignition and explosion.

Packaged Ammonia Chillers:

• Packaged ammonia chillers generally operate on a compression refrigeration cycle with capacities ranging from 20 to 400 tons of refrigeration.
• The ammonia load in packaged chillers is low, approximately 1 pound per ton of refrigeration.
• Smaller capacity packed ammonia chillers use a piston compressor, while larger ones employ a screw compressor.
• Packaged ammonia chillers are factory-assembled, enabling quick and easy installation of the system.

Where to learn all about chillers?

We offer comprehensive training in chilled water installations with chillers.

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