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Support
• An R-1234yf calibrated gauge set with dedicated R-1234yf couplers . As R-1234yf is an A2L mildly flammable substance , SAE standards have been developed for hoses and couplings .
• Red and blue service hoses : the fittings are 12mm O Ring fittings male with a hexagon nut . R-134a is ½ ” female . R-12 - commercial industry standard - is ¼ ” flare female with a knurled nut .
• R-1234yf has a unique vehicle quick release fitting , to prevent use of incorrect equipment not fit for this type of refrigerant .
• Yellow service hose ½ ” LH acme thread . An adaptor is available to fit a universal vacuum pump .
• The manifold gauge set is designed to take the male fittings of the hose set and are calibrated to read R-1234yf temperatures .
• Electronic refrigerant leak detector A2L compliant .
• Vacuum pump A2L compliant .
• Recovery / reclamation equipment A2L compliant . Although it is not mandatory to recover R-1234yf , it is still good environmental practice and due to the cost of this refrigerant it would be advisable to do so .
• Dedicated cylinders for recovered or new R-1234yf have a left-hand valve thread and require a suitable adaptor to connect to the gauge set charge hose . As R-1234yf is a mildly flammable gas , cylinder storage and transport practices differ to R-134a cylinders .
IS R-1234YF COMPATIBLE WITH EXISTING R-134A EQUIPMENT ? No . The R-1234yf system refrigerant circuit is accessed using service couplers that are a different size to those of a R-134a system . The service coupler hose connection also has a left-hand thread that requires a matching hose for connection . Hence the need for an R-1234yf gauge set .
R-1234yf is classified as an A2L mildly flammable refrigerant and requires the use of equipment designed for use with such a refrigerant . The exception is an electronic leak detector . Several manufacturers produce detectors that are suited to both refrigerants .
CAN A R-134A SYSTEM BE CONVERTED TO R-1234YF ? No . R-134a systems were not designed to operate using a flammable refrigerant . R-134a systems should not be converted to use R-1234yf as these systems are unable to be converted to a level that satisfies the requirements of international standards set for systems that use R-1234yf . The standards lay down specific requirements for system design . For example , the R-1234yf evaporator is significantly stronger than the one you would commonly find in an R-134a system .
Aside from the safety aspects , although the two refrigerants have similar thermodynamic properties , they are not the same . Therefore , compressor damage or system performance limitations may be experienced by attempting to convert an R-134a system to R-1234yf .
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RACA Journal I May 2024 www . refrigerationandaircon . co . za