Frequently Asked Questions

What is RS-44b?

RS-44b is a non ozone depleting Drop-in replacement for R22 in most applications.

Yes, but what does RS-44b contain?

RS-44b is a blend of R125, R32, R134a, R227ea, butane, & isopentane.

Is RS-44b subject to a phase-out program under any regulations as is the case with the CFC and HCFC?

No. None of the components of RS-44b is subject to a phase out schedule under the Montreal protocol or any regulations

Can RS-44b be used with mineral and alkylbenzene lubricants?

Yes. There is no need to change to a synthetic polyol ester (POE) oil with RS-44b which operates satisfactorily with traditional lubricants.

What is the temperature glide of RS-44b?


Is RS-44b non flammable and non toxic?

RS-44b is both non-flammable and non toxic. RS-44b is non-flammable under all conditions of fractionization under ASTM 681-98. It is ASHRAE certified s A-1, meaning it is non-toxic and non-flammable.

Is RS-44b approved by compressor manufacturers?

The individual components which comprise RS-44b are widely used in compressors produced by major manufacturers. RS-44b has been used worldwide for fifteen years in all types and brands of compressors successfully.

What is the compression ratio of RS-44b?

High compression ratios can result in increased energy expenditure and the potential for compressor damage. RS-44b has a compression ratio which matches R22 across the range of applications where R22 is commonly found

Can RS-44b be used to top up a system containing R22?

The Environmental Protection Agency (EPA) in the United States does not permit the mixing of different refrigerants. However, it is known from experience in Europe that the unintended mixing of RS-44b with R22 will not generate higher pressure readings, loss of efficiency or component damage.

Is RS-44b as efficient as R22?

Tests show that RS-44b has a higher Coefficient of Performance than R22 and hence is considered to be more energy efficient than R22.

What trials have been carried out on RS-44b and what are the results?

RS-44b has shown comparable results to R22 in systems where an expansion device is present. RS-44b is particularly effective at low temperatures. The results show good oil return to the compressor.

Does RS-44b need to be charged in the liquid or gaseous form?

Because RS-44b is a blend, the recommendation is to charge it into the system in the liquid form. However, if the entire contents of the cylinder are being charged, then vapour charging is acceptable.

Does the RS-44b disposable cylinder have a dip tube?

No. The disposable should be inverted to discharge RS-44b in the liquid form.

Is RS-44b on the SNAP (Significant New Alternative Policy) list in the USA?

Yes, RS-44b is on EPA’s SNAP list for sale in the USA

Has RS-44b got an ASHRAE number?

Yes. RS-44b has been designated a refrigerant number of R453A by the ASHRAE & a safety classification of A1, namely low toxicity & non flammable under all conditions of fractionation.

How does the pressure rating of RS-44b compare with R22?

The discharge pressure of RS-44b is about half a bar higher than R22.

How does the capacity of RS-44b compare to R22?

The capacity of RS-44b matches R22 from high to low temperatures across the temperature range where R22 is commonly found.

How does the temperature rating of RS-44b compare to R22?

The discharge temperatures of RS-44b are lower than R22.

What are the flammability characteristics of RS-44b?

RS-44b is non flammable as formulated.

What are the decomposition products resulting from the combustion of RS-44b?

The decomposition products resulting from subjecting RS-44b to a high temperature source are similar to those when R22 is exposed to fire conditions. The decomposition products in each case are irritating and toxic, and breathing apparatus should be worn where a possibility to exposure exists.

Are there any special precautions with RS-44b?

There are no specific precautions which must be taken with RS-44b. As with all refrigerants, common sense and good housekeeping is always recommended. Because the use of hygroscopic synthetic POE lubricants are avoided with RS-44b, scrupulous attention to preventing moisture contamination is not necessary, although the ingress of moisture should be avoided at all times.

Is RS-44b compatible with refrigeration and air conditioning systems designed for R22?

Yes. RS-44b is compatible with all materials commonly used in systems that were designed and charged with R22. As in the case of R22, magnesium and zinc alloys should be avoided.

Can RS-44b be recovered and recycled?

Yes. RS-44b can be recovered and re-used after a cleaning process such as reclamation

What technical guidance do you advise when changing from R22 to RS-44b?

The procedure for converting from R22 to RS-44b is straightforward. Use the same type of lubricant, replace the filter/drier and charge the same quantity of RS-44b as the original R22 charge after fully evacuating.

How does RS-44b compare in price with other R22 alternatives?

RS-44b is competitive in price with other R22 alternatives.

What is the main advantage of RS-44b?

RS-44b has a lower GWP than most replacements for R22. RS-44b is a suitable replacement for R22 across the range of temperatures where R22 is commonly found at high and low temperatures. RS-44b can be used to replace R22 without the need to change the original mineral oil in the system. Therefore, it is not necessity to retrofit the system to a synthetic lubricant such as POE.

Is RS-44b compatible with hoses, seals, gaskets and O-rings commonly used with R22?

Yes. Because the original mineral oil is being used and not a synthetic lubricant, elastomers and plastics used with R22 are compatible with RS-44b.

How does the Coefficient of Performance (COP) of RS-44b compare with R22?

Tests show that RS-44b provides a higher COP than R22 depending upon the application, equipment and system design…all these are factors.

What is the specification for RS-44b?

RS-44b complies with the refrigerant specification AHRI 700 – 2004 for fluorocarbon refrigerants.

What is the effect of high exposure by inhalation of RS-44b?

As is the case with all CFC, HCFC and HFC based refrigerants, high exposure to RS-44b may produce anaesthetic effects. Very high exposures may cause an abnormal heart rhythm and prove suddenly fatal as is the case with all CFC, HCFC and HFC based refrigerants.

What is the flash point, flammability explosion limits and auto-ignition temperature for RS-44b?

RS-44b is non flammable as formulated and does not have a flash point or explosion limits. The auto-ignition temperature of RS-44b has not been determined but is expected to be greater than 750ºC

What types of leak detectors should be used with RS-44b?

Leak detectors used with HFCs are suitable for use with RS-44b.

What would be the effect of a large release of RS-44b?

In common with other refrigerants of this type, the area should be immediately evacuated. The vapour may concentrate at floor level and in poorly ventilated areas may be slow to disperse. Forced ventilation should be provided before entering such areas.

Is RS-44b available in both returnable and disposable cylinders?

Yes. It is available in 125 lb. and 1,000 lb. deposit cylinders.

Can RS-44b be added to systems containing R22 or RS-44 (R424a) without materially affecting the performance of the whole system?

First and foremost, the EPA does not condone, recommend or approve of mixing any refrigerants. However, RS-44b does not form an azeotropic mixture with R22 or RS-44 (R424a). Therefore, if a technician inadvertently or unknowingly adds RS-44b to R22 or a system containing RS-44 (R424a) the system will not generate any higher pressures and should operate as normal without any harm to system components.