Greencool refrigerants

download R 411B Thermodynamic table chart (Excel 7.0) download PH diagram (Microsoft Word 97)
Conversion Procedure Using Greencool R 411B as a single refrigerant.
Whilst Greencool R 411B was developed as drop in replacement for R502 and R22, further research has shown that it will operate in most systems currently using nearly any refrigerant. The benefits of the use of one refrigerant for most applications instead of an array of separate refrigerants, gives a reduction in cylinder holding. As Greencool R 411B works differently to most alternatives, detailed below are particular guidelines that must be followed when using R 411B in addition to following good refrigeration practice. In most applications R 411B will achieve faster pulldown temperatures and also lower temperatures. Some adjustment to the controls may be required if previous temperatures are to be maintained.
Always charge in liquid form. Do not overcharge
R 12 Conversions Charge. The refrigerant charge is normally between 50 -70% of the R12 charge removed from the system. When converting charge the system in liquid form to approximately 50% of the original charge then add further refrigerant in liquid form until correct system operation is achieved. On converting R12 it is important that the condensor is clean & maintained to assist in reducing high head processes. TEV Adjustment Set superheat as R502. On a system where evaporator pressure/temperature & T is important as R 411B provides more duty it may be necessary to change the orifice or the TEV. It is recommended that an R22 MOP valve is fitted. (eg cellar cooling where a close differential thermostat is used and no defrost is provided).
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R22/R502 Conversions Charge. When converting charge the system in liquid form to approximately 70-80% of the original charge then add further refrigerant in liquid form until the correct system operation is achieved. (If system is fitted with sight glass, just clear - no further refrigerant to be added). TEV Adjustment TEV adjustment may be required to achieve recommended design superheat, of between 5-7K.
R134a Conversion The situation as R12 applies
R404A Conversions Check TEV & orifice. The TEV may need to be adjusted and the orifice changed to a smaller size
R500 Conversions The situation as R12 applies
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Others R 411B will operate in most systems that currently use R22, R407C, R134a, R404A, R408a R500, R12, R502 or any other alternative refrigerant that operates in the same pressure/temperature environment.
Pressure Controls Check all pressure switches and fan control switches are set for the correct operating pressure of R 411B. Set pack controllers for required evaporator pressure/temperature (see T.D. Tables).
Lubricants Follow compressor manufacturers guidelines. R 411B will operate in any lubricant that is used with any of the refrigerants noted above.
Fixed Capillary Systems R 411B will operate in most applications where fixed orifice or capillary control is employed. Greater care must be taken to obtain correct refrigeration charge - do not overcharge. (Energy savings cannot be guaranteed.)
Expansion Valves Thermostatic Expansion Valves - All applications. For correct pressure/temperature relationship and flow rates it is recommended that an R22 TEV is fitted for optimum performance.
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Electronic Expansion Valves Using electronic expansion valves, the valve coefficient and sizing must be checked and adjusted/changed if required.
General Always check control thermostat(s) are set to the correct temperature requirements. These guidelines are based upon the assumption that the system being converted is correctly sized. It may be necessary to change oil/refrigerant filters on larger, old systems after conversion due to any system residue being flushed out by the new refrigerant charge.
Not Recommended Whilst R 411B has been run in most systems, we do not currently recommend its use in:- 1. R12 York 210 (flange valve) compressor due to incompatible shaft seals. 2. Automotive Air Conditioning 3. Centrifugal Compressors 4. Natural rubber hoses used on R12 must be changed as they are not compatible with R 411B 5. Domestic Refrigerators
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