just chilling
28-01-2010, 01:41 PM
Hi Guys i have been reading the thread below posted by littleyaper.
this brings up a few topics.
leaks as stated by Grizzly and Coolconcerns directors at my F Gas 2079 course. if the present/previous CFC,HCFC and now HFC gasses did not leak as often as they presently do, and were made of durable components just like present industrial amonia systems, then we probably would not be faced with R22 phaseout. overall we as an industry failed to address the problems and governments stepped in with the aid of funds from the chemical gas companies, now F. Gas regs apply and chemical companies benefit from the sale of new gasses. yes hydrocarbons are great refrigerants, but i have seen several newspaper reports of exploding HC gas fridges. again a leak problem???
R400 series drop ins R417a R422a R422d R438a also known as isecon 9 series... see duponts web site.
has anyone realised that these gasses are made up from a blend of R125 and R134a typically combined to 95% of gas volume and a small percentage of hydrcarbon such as butane or propane to aid oil return.
as most of you will know R134a is not an efficient gas its specific heat capacity is poor so the compressor has to be bigger or work faster to circulate the same amount of duty as a more efficient gas, that has a higher specific heat capacity.
Europe is trying to ban R134a as a refrigerant in motor vehicle air con, no doubt the rest of the refrigeration industry will have to folow, again the chemical companies will prosper.
my company has undertaken several R22 retrofits we have encouraged the clients to replace the mineral oil to POE oil. these retrofits have to date been successful. however stories are filtering back to us from other companies that have left the mineral oil in the system and sufferd bad oil dilutuion problems resulting in a lack of oil pressure.
in addition good consideration needs to be given to new potential leak sources from 'O'seals and shaft seals.
in my opinion no manufacturer will make equipment to run on R417a R422a R422d or R438a. as these are less efficient than R404a on low temp or R410a on high temp/ or air con.
Co2 seems technicaly too challenging because of critical point being close to 25 degC.
why not ammonia central plant contained in an approriately designed plant room and glycol secondary refrigerant circulated in the field.
this brings up a few topics.
leaks as stated by Grizzly and Coolconcerns directors at my F Gas 2079 course. if the present/previous CFC,HCFC and now HFC gasses did not leak as often as they presently do, and were made of durable components just like present industrial amonia systems, then we probably would not be faced with R22 phaseout. overall we as an industry failed to address the problems and governments stepped in with the aid of funds from the chemical gas companies, now F. Gas regs apply and chemical companies benefit from the sale of new gasses. yes hydrocarbons are great refrigerants, but i have seen several newspaper reports of exploding HC gas fridges. again a leak problem???
R400 series drop ins R417a R422a R422d R438a also known as isecon 9 series... see duponts web site.
has anyone realised that these gasses are made up from a blend of R125 and R134a typically combined to 95% of gas volume and a small percentage of hydrcarbon such as butane or propane to aid oil return.
as most of you will know R134a is not an efficient gas its specific heat capacity is poor so the compressor has to be bigger or work faster to circulate the same amount of duty as a more efficient gas, that has a higher specific heat capacity.
Europe is trying to ban R134a as a refrigerant in motor vehicle air con, no doubt the rest of the refrigeration industry will have to folow, again the chemical companies will prosper.
my company has undertaken several R22 retrofits we have encouraged the clients to replace the mineral oil to POE oil. these retrofits have to date been successful. however stories are filtering back to us from other companies that have left the mineral oil in the system and sufferd bad oil dilutuion problems resulting in a lack of oil pressure.
in addition good consideration needs to be given to new potential leak sources from 'O'seals and shaft seals.
in my opinion no manufacturer will make equipment to run on R417a R422a R422d or R438a. as these are less efficient than R404a on low temp or R410a on high temp/ or air con.
Co2 seems technicaly too challenging because of critical point being close to 25 degC.
why not ammonia central plant contained in an approriately designed plant room and glycol secondary refrigerant circulated in the field.