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Technological challenges in servicing of Mobile Air Conditioners (MAC) and overcoming methods
ISSN: 0148-7191, e-ISSN: 2688-3627
Published November 27, 2013 by SAE International in United States
Annotation ability available
Event: 8th SAEINDIA International Mobility Conference & Exposition and Commercial Vehicle Engineering Congress 2013 (SIMCOMVEC)
Mobile Air Conditioner's (MAC) are becoming part of every mobility solution, both for goods and people. Developed nations have started reigning in the side effects for inevitable use of refrigerants during usage and service. The most stringent and current regulation related to servicing of MAC is SAE J2788 for R134a refrigerant.
This paper will discuss the parameters influencing AC service and challenges there by.
The SAE J standard mandates recharge accuracy of ±15°g at 21 to 24°C temperature on Chevy Suburban for a target charge quantity of 1360 g. Though the standard is limited to testing condition at laboratory temperature, actual conditions in a service workshop would demand higher degree of fine tuning to meet efficient functioning of MAC, despite many controllable and uncontrollable variables. This paper would examine some of such variables and technological approaches adopted in achieving the above requirements.
Typically non SAE certified AC Servicing machines may have accuracy of performance limited to certain operating conditions and standard physical constructions. Any change in the above parameters like deviation setting in force sensor due to transportation, operation of machines with non factory fitted hoses, variation in reservoir capacity or varying target charge quantity requirements will have manifold impact on accuracy.
The methods adopted predominantly can be classified as design innovation of mechanical engineering components and novelty in algorithms of control engineering.
The innovations in mechanical engineering would delve deep into sustainable component development to overcome situational challenges disrupting the accuracy of machine like variation in force sensor values. The novelty in SW algorithms considers discerning selection of electronic components matched with close control on SW variables.
CitationKashyap, R., Kumar, S., and G K, V., "Technological challenges in servicing of Mobile Air Conditioners (MAC) and overcoming methods," SAE Technical Paper 2013-01-2878, 2013, https://doi.org/10.4271/2013-01-2878.
- SAE International Surface Vehicle Standard, “HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/ Recycling/Recharging for Mobile Air-Conditioning Systems”, SAE Standard J2788, Rev. Dec. 2006.
- SAE International Surface Vehicle Standard, “Standard of Purity for Recycled R-134a (HFC-134a) and R-1234yf (HFO-1234yf) for Use in Mobile Air-conditioning Systems”, SAE Standard J2099, Rev. Feb. 1999.
- Parrino, M., Dongiovanni, M., Milone, M., and Chiara, M., “Influence of Receiver Capacity on the Refrigerant Charge and on the Performance of an A/C System,” SAE Technical Paper 1999-01-0871, 1999, doi:10.4271/1999-01-0871.
- Coolpack software, Version 1.5, IPU & Department of mechanical engineering, Technical university of Denmark