Right now you know you have a bit too much, but with a CR4P compressor this is an insurance policy. Yep, definately not a meat locker. Its highest value is 1. Until 1995, most cars with air conditioning used R-12 Freon refrigerant which has shown to have an environmental impact. It's best to determine on a case-by-case basis while monitoring system pressures and output air temperature. There is NO reason to retrofit a vehicle to R-134a as long as the R-12 system is cooling properly and contains a normal charge of refrigerant. The system has been previously converted to R-134a. I put one in my old daily driver '79 Chevy tank (r-12), and it really made a difference. The pressure at low temperatures is nearly the same between 12 and 134a. These differences in the valve size can be attributed to the correlation of the cooling capacity with the enthalpy difference and the mass flow, which in . Instead of using R12, its preferable to use R134a because it is very easy to find in the market, its sold at an affordable price, and is environmentally friendly. J.Harris said: Or if you want to do it like they do in Mexico you can use propane, it's an excellent refrigerant but highly flammable. Even with proper fan operation, missing seals & air dams can effect condensor effeciency. When the temperature is reduced to-7C or below, the plants ability to cool the airdrops significantly. With the A/c off hi and lo were both at 105psi. 3) A/C Compressor Always On. But, if your car lacks enough condenser and you have many 100+ degree days then you may want to stick either increase air flow, add another condenser as we mentioned in The Mr. Ice Project or stick with R12. And no, you cannot "drain' excess oil out. One of the differences between auto air conditioners that have been redesigned from R12 to R134a is that the condensers have gone from serpentine to pseudo-parallel. That switch should close @ 52c. If 50 degrees across the cond. I cleaned the evap as best I could, if that is what you are getting at. Skin contact: If the R134a (liquid) comes in contact with your skin, it could cause a burn. Then at least I'd know really where I am on it. Statisicaly your friend was lucky. 42 (at best) w/ 134A in 2000 isuzu trooper. The most common influences which effect the capability of R134a to perform well are the condenser, in some cases the the superheat setting of the expansion valve or the amount of R134a. They examined the two configurations of capillary tubes i.e. R12 is used in several applications like low temperature, medium temperature, and high-temperature applications. What was the ambient when you took that reading?Jumpering the aux fan is a common thing here in the desert. So, instead of using R12, other better options include R401b, R134a, R401a, etc. The current expansion valve is FF - 1/4 - C. Is it neccesary to replace this valve? It's not just the poor performance - the cooling just stops working after a while. . The compressors used by refrigeration plants to compress gas require oil to help lubricate its moving parts. _____ 2012 E350 2006 Callaway SC560 . 4) Inconsistent Airflow. However, take note that R134a refrigerants are manufactured specifically for automotive air conditioners. Then when it is switched off for a few minutes and then back on, the air cools again. System has been working fine for a year. leading to corrosion of expansion valves, capillary tube plugging, and compressor bearing . R-401b is the mixture by weight of 61% R22, 11% R-152a and 28% of R-124. In most cases, the systems used have varied components, designs, and service ports. One of the differences between auto air conditioners that have been redesigned from R12 to R134a is that the condensers have gone from serpentine to pseudo-parallel. A slow loss of cooling at city speeds is usually related to condensor capacity & airflow issues.You could improve the cooling capacity by replacing the condensor with a high effeciency parallel flow unit. A. Pressure/temperature table for R12, R134a, and R513A is shown in Figure 1. . In the automotive world, the replacement for R12 was R134a. This would become an expensive investment for a repair or service station to have unique dedicated equipment for every type of alternative refrigerant. I'm thinking of jumping the temp switch and leaving the fan on to see how it does. Its chemical symbol is CH2FCF3. Also, since R134a uses synthetic oil, it has a low global warming potential, unlike R12 which uses mineral oil which poses a negative environmental impact. If not, you just don't know unless a test is performed. The ratings for evaporator temperatures 40F, 20F, -10F, -40F in the capacity tables are in accordance with ANSI/ARI = R134a Charge Level R12 Expansion Valve = 201 830 06 84 R134A Expansion Valve = 201 830 04 84 Is there a difference after all? The symbol implies that R12 is a composite of carbon, chlorine, and fluorine. ESP when a compressor has frozen. With the knowledge of the differences, youll be able to draw a comparison between R12 vs R134a efficiency. A comparison between R12 vs. R134a temperature will show that R12 has a higher temperature than R134a. In this study, without the need for major modifications to the bus air conditioner, the variation of the ejector dimensions according to different parameters has been investigated in the case of using the R1234yf, R1234ze(E), or R600a refrigerants, which may be a substitute for R134a as a refrigerant due to . There is only a temperature switch on these cars as far as I recall, and it just switches on the aux fan. You may have heard of a friend that did the job himself with borrowed equipment and 12 or 16 ounce cans of refrigerant. We recently created this blog site to enable us to share our knowledge with other automotive mechanics and car owners. and he synthesized R-134a in 1936, 5 years after R-12 was . Can I use the one for the R-12? This allows the refrigerant in the condenser to be void of oil particles. So to keep things simple and to avoid controversy and politics we have R134a. Most of all the differences gravitate to longevity, functionality, and safety. Like say half a can or so recharge come springtime warm weather or something. Stopleak is also risky. Plus, not releasing the chemical into the air is morally justifiable. R12 is otherwise called dichlorodifluoromethane is a colorless gas (chlorofluorocarbon halomethane (CPC) that is used as an aerosol spray propellant and a refrigerant, and is soluble in organic solvents. R134a is called tetrafluoroethane (HFC). According to Wikipedia, There is such a thing as "r132a" (1,1-Dichloro-2,2-Difluoroethane), however there is no indication of it being a commercially produced refrigerant. Bad Car A/C Expansion Valve Symptoms. It may take a couple of tries to get things really clean.The laser is usually close on clean surfaces, but I prefer a T/C. The P H and T cond,sat of the HR12 at a T oa of 40 C were higher than that of the R134a, resulting in a higher P e than that for the R134a. It is common for eurocar threads to go multiple pages, and as Nick points out - sometimes cool is all you will ever get. GWP is a measurement of Greenhouse Gases and their effect on Global Warming. The bad thing is I don't know what to do about it. We say generally because the vehicle manufacturer may have a formula already worked out for the R134a conversion process. If the system was upgraded by a professional it should have an upgrade sticker. R12, on the other hand, has an ozone depletion potential of 1, implying that it can damage the ozone layer. Recomanem consultar les pgines web de Xarxa Catal per veure tota la nostra oferta. All pre-97 XJs use systems with the same basic operating principle, although the parts do change a bit. A Lot of the fins are bent, especially at the top. -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a, Hi pdrayton- If you can remember the oil capacity that you found in all your research and post that, then bohica and others can have a better idea if you have too much; see if you can find that info! Nevertheless, if your application is configured only for R12, then you can use it or consider replacing the applications engine. Quick View. R134a has a smaller molecule than R12 so R134a will leak out sooner than R12. Pound for pound R134a is a more efficient refrigerant than R12, however it runs at higher pressures in some aspects and therefore requires more effective condensing. Performance doesn't seem to have improved. R-134A has a slightly lower pressure at evaporator temperatures (30-40 degrees), but R-134a also has a much higher pressure at condenser temperatures (120-150 degrees). Trinary Pressure Switch quantity. We chose to use 5-6 ounces of oil to be on the safe side: 3-4 ounces for the compressor, 1 oz of oil for the drier and another ounce of oil for system losses. and feeds it through an expansion valve. Before landing on the debate of R134 vs R12 you should know that both R134a and R12 are AC refrigerants types used in refrigeration and air conditioning systems. Environmental Impact: When R134a escapes into the atmosphere, it contributes to global warming. The chemical composition of R12 and R134a differ. Its chemical symbol is CCl2F2. Also, they are mostly used in refrigeration and automotive air conditioning systems. 1.5 ounces - hmmm. Agram a retevis rt22 password i bastrop county district clerk records el material que oferim als nostres webs. If the charge is low the compressor will cycle on/off in the max AC position. by | Jun 21, 2022 | what is the most accurate latin translator | burlington iowa arrests | Jun 21, 2022 | what is the most accurate latin translator | burlington iowa arrests By noting the ambient temperature you can look up what the preferred high side pressure should be. Is there a graph? Anyone know what happens when an R12 expansion valve is used in a system charged with R134A? The reason is that the vehicles, for instance, manufactured currently configure the engine for R1234yf refrigerant, making no provision for replacement. Tamb oferim en VOSC el contingut daquestes sries que no es troba doblat, com les temporades deDoctor Who de la 7 en endavant,les OVA i els especials de One Piece i molt ms. What is the refrigerant property involved that has caused this? Took me a while to figure that one out, and how to say that. 1) Look Here at the available sizes of PF condensors.2) Go look at your vehicle's condensor & mounting. Before we mentioned that you can add approximately 5-6 ounces of ester oil to the compressor. 4 Stars & Up & Up; 3 Stars & Up & Up; 2 Stars & Up . The condenser water inlet temperature and flow rate are controlled with the use of a . So if you car has a large amount of rubber hose, such as a 40 feet with the 911, then you will be re-charging the system often and that is expensive no matter which refrigerant you use. Gnats & mosquitos will clog deep. The only difference I can imagine would be the recharge connection. Back in that era, my business associates drove those things, brand new, and maybe I should take my Cadillac instead, no they wouldn't be caught dead in a Caddy, people of our esteem should be driving an MB. A/C Expansion Valve Replacement Cost. Is that why expansion valves are specific to R12 or R134A? Thus, when the system is running, condensing the CO2 is not a problem. This is because R134a. Any advice appreciated. Don't like the sound of custom parallel condensor. R404a for freezing of product. Fitting a PF condensor is not rocket science, but it requires some planning. However, you can convert R12 to R134a by yourself, save money and keep all the tools purchased. Since you will be using less R134a than R12 you do not want to rely on the driers site glass to determine if the system is full. -------------------------Just another brick in the wallHad a little mule I fed him castor oil and every time he jumped the fence he fertilized the soil, The older expansion valves were filled with the refrigerant they were used with, the replacement valves (today) are filled with a different chemical to work with both refrigerants..Hope this helps-------------------------ChickEmail: Chick---------------------------------------------Freedoms just another word for nothing left to lose, I believe the optimum supercool setting will vary slightly between an expansion valve for an R12, as compared to R134a, system. B. Remove the old mineral oil from the compressor by turning it upside down, side to side, and turn the front hub on the clutch assembly. in /nfs/c05/h04/mnt/113983/domains/toragrafix.com/html/wp-content . Can I use the one for the R-12? And, unfortunately a small high side pressure gauge on a short hose. R134a has an ozone depletion potential of 0, implying that it has a slight effect on the ozone layer. #19. If he is not in the garage fixing challenging mechanical problems, he is writing automotive repair guides, buyers guides, and car and tools comparisons. The adjusted tension of this spring is the determining factor in the opening and closing of the expansion valve. Maybe a jerky locker.I cleaned the condensor with the off the shelf ac cleaner stuff from Home Depot that I used on my home evaporator. . So I probably put the highest suggested amount in to be safe. we convert older systems where i work all the time and they work fine. difference between r12 and r134a expansion valve . CLUTCH CYCLING SWITCH. Best for varieties of operating conditions: Its boiling point is -21.6 Celsius. I've done the FSM test and with 81F ambient, the vent should be 50F. Yes, the 50F diff (160-110F) on the condenser was at idle, and ambient was about 90F. Talk about what services you provide. El maig de 2016, un grup damics van crear un lloc web deOne Piece amb lobjectiu doferir la srie doblada en catal de forma gratuta i crear una comunitat que inclogus informaci, notcies i ms. If your car does not have a high pressure cut-out switch in the AC system then youll need to have one installed (call us if you need help). To bless the system the technician should attach a R134a sticker somewhere in the engine compartment to note the car is using R134a. Hope this helps. A vacuum pump, a refrigerant recover system, quality service gauge set with both low and high side gagues, and much more besides the lessons to learn what to do and what not to do. ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. Thomas Jefferson, Thanks,OK, I'm starting to feel a little better about it. This is due to many facts: R134a refrigerant is about 10% less efficient in moving heat than R12! Inasmuch as R134a has a global warming potential thats over 1000 times more threatening than carbon dioxide, its better than R12. ing the expansion valve, a maximum opening superheat of 7F, and a standard factory air test superheat setting. I think so. I've got a ball valve I'm going to put in the coolant line before the coolant goes through the firewall to the core. Anyone know what happens when an R12 expansion valve is used in a system charged with R134A? R12 Expansion Valve = 201 830 06 84 R134A Expansion Valve = 201 830 04 84 Is there a difference after all? is good, then I should be looking elsewhere? Well, I'm not sure it is 'fine' - it doesn't cool very well in 95F weather. The non-flammables can have R22 type gas which is not compatible with most rubber hoses or they have gases that contribute to global warming. Gain access to our free AOP (Ask a Professional) Section to get real answers for your questions. The crossover point is approximately at 64F. $21 . Measure what you have now.3) Go back to the page in step one, and find the largest condensor you can put in your vehicle. Then I'll put the ball valve in on the coolant and test it and see what we have. Replied by Rich928 on topic R12 or R134a. I'm doing one thing at a time so I know what the cause was. 4) Repeat step 2, making sure it will fit. On the other hand, R12 has a global warming potential of 10,910. Some compressor manufacturers or OEMs suggest PAG type oil for R134a. Have a look in the FAQ Section, and look for "Fan clutches & testing them". I found that in the..Maxposition on the control it will have the compressor running all the time. R134a was selected as a replacement refrigerant for R12 because R12 contains chlorine and has a major effect to ozone layer depletion. I don't think it has any air dams or seals, I'll check to make sure. Thanks so much Bohica - you've save me many more hours of fruitless speculation. I bought a relay to put on it connected to the compressor clutch. AFAIK, there is no clutch on the engine fan on the 240D. So the steps involved are cleaning out the old oil, replacing all the O-rings, replacing the dryer, replacing the expansion valve, and converting the high and low side connectors from Schrader to quick connect valves. Als nostres webs oferimOne Piece,Doctor Who,Torchwood, El Detectiu ConaniSlam Dunkdoblats en catal. Some 1993 and older R12 systems aren't as 'compatible' as you'd think to switch over. Look deep into the fins. June 21, 2022 difference between r12 and r134a expansion valve . Carefully study the chart and compare the following: To a large extent, the choice is up to you. 3 ounces? Compared with the cost-performance ratio, R507 is 30-40% . Whenever its exposed to the environment, it changes to a gas. For example, at an evap temp of 30 (your daughter's system is probably running around 25-28 saturated in order to give a 32 duct temp), the pressure of R-134a is 26.1psi. Then, subtract that result by 0.25 pounds to get the proper amount of R134a charge. Related products. It is a known suspect that lets heat into the heat exchanger/core even when off because the mono-valve is on the exit side of the heater core. This is a great space to write long text about your company and your services. You will be fine with a 134a-compatible TXV running R12. Blows pretty hard on full. Also, R134a cylinders are light-blue in color. Large temperature difference between expansion valve inlet and outlet oReplace expansion valve Air . Theres no problem with using R134a in a home air conditioning system because it is a hydrofluorocarbon that doesnt cause environmental harm. But as there's not a big difference, people say you can suffice with either. Stay home and grill your own steaks and stir your own martini. Could that be screwing up the systems performance?Anyway, when I installed the system, the new TXV (is that short for expansion valve?) The substitute that we used for R-12 was the new HFC called R-134a. difference between r12 and r134a expansion valve why is miles raney not on homestead rescue June 21, 2022. manila mayor candidates 2022 I had a pair on my SAAB that seemed ok - but new ones ran 20% faster!Your best clue to airflow issues is a 60 mph test. We've updated our forums!Click here to visit the new forum, Year: 1991Make: Jaguar Model: XJ6Engine Size: 4.0. Welcome to rxmechanic.com. For instance at 25 F the pressure of R-12 is 24.6 PSI and the pressure of R-134a is 22.1 PSI. (You must log in or sign up to reply here. July 3, 2022July 3, 2022. R-12 expansion valves can be re-used, but will not be as efficient as R-134a specific ones because of the slightly different pressure specs of R-12 vs. R-134a. The mechanical fan & clutch should be checked as well. The difference really shows up on the high side. I don't believe it is but I had a service guy tell me it needs to be done. R134a systems operate at higher discharge-side pressures than R12, which can cause compressor seals to leak. Lets take you through the advantages, disadvantages, and differences of these two refrigerants a detailed comparison including R12 vs R134a performance. Hence, let us continue to fix it. R 134A is designed for the high demands of an automobile AC and cannot be used on refrigerators due to pressure differences. -The amount of R-134a needed will typically be 80-90% of the R-12 charge. It can be used applications like walk-in coolers, food and dairy display cases, domestic refrigerators, and beverage dispensers and vending machines. You do not want to exceed the systems high side recommendations. maintain the A/C of older cars. R12 systems used mineral oil, but unfortunately mineral oil doesn't dissolve in R134a. If ambient is 90 (today) and the output of the condensor is 110, that's pretty good isn't it? That would be the "black death" syndrome. That's a lot isn't it? R12 is highly destructive to the earths ozone layer. But I've read that these car's didn't do too well in the a/c stakes, so that might just be as good as it gets. I had to vaccum the system for 2 hours and recharge 4 oz of PAG oil plus 36 oz of 134A freon (3 cans). Also, it can be used with all types of compressors. I put in a new (not reman) compressor (R4 I believe it is) in my merc 240D, new drier, new expansion valve, new o-rings, nylog. The first vehicle that used the R1234yf refrigerant was the 2013 Cadillac XTS. leading to corrosion of expansion valves, capillary tube plugging, and compressor bearing . The expansion valve(Tx) is in the car at the inlet line to the evaporator with compressors you best get advice from an ac specialist shop as the differences could be the gas that it pumps some systems use R12 and others use R134a or later gas yes R1234yf Freon gas can be replaced by R134a; the newer systems were designed with this in mind so no, there will be no damage to the compressor but some time in . For instance you can evacuate FRIGC FR-12 into a refrigerant recovery bottle that has R134a in it or visa versa. There are significant differences between R12, R134a, and R513A, which must be considered when handling, processing, applying, or retrofitting with these refrigerants. Generally this works well for the whole system. The problem with using an approved alternative refrigerants other than R134a is that when the system is serviced it requires certain types of fittings, labels and dedicated equipment. . #13. Once you have replaced the OEM condensor with a PF unit, you will need to make custom hoses to mate with your OEM system. The next piece of equipment to track down leaks is a leak sniffer. shown for the parallel flow, aluminum condenser that is listed. I don't want to be chasing ghosts. At the time I thought nothing of it, but now I am thinking maybe that is contributing to the system not working as well as it could. 4.R404A R134a increased mass transfer resistance to reduce the transmission chamber heat coefficient, while R507 heat transfer coefficient is higher than R404A. R-134a can actually cool better than R-12 in a well designed R-134a system as it has better thermoconductive properties, but all the high pressure issues have to be addressed.But even when these cars were brand new, didn't cool worth a damned, recall almost dying in one in Las Vegas at the time, but a good way to lose weight with gallons of perspiration pouring out, just don't let that drip on the seats, that is inappropriate. Make sure to get the R12 EXP valve if that is the way you go. If your compressor requires replacement or its seals and o-rings need to be replaced due to leakage, it would be wise at this time to either obtain a compressor that has o-rings and seals that are compatible with R134a or have your unit re-manufactured with compatible components. Spray it deep, and let it sit for a few minutes. Depending on which circuit diagram fits your car (cough, no vin list exists) you have either one or two switches controlling the aux fan. Should I do the test again with the the aux fan jumpered? R134a refrigerant fittings are different size. I have some experience with auto a/c but not too much. They might say for instance, add 3-4 oz of oil to the compressor, 1 oz of oil for when you replace a drier, 2 oz oil for the evaporator and so on. The system has been previously converted to R-134a. . ). Are r12 and r134 fittings different? According to the thermodynamic characteristics, it is close to the R12 freon, however, it is 10-15% worse in terms of cooling capacity and is more fluid. -------------------------"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest." Also, would a genuine R12 TXV be better, or is it too marginal to worry about?I think I should do the FSM test for performance - they have a graph with ambient temp and a/c temp. I'm curiousSo there is work to do, ie performance should be able to be improved. You'll get marginally better performance out of the change as the expansion valve is matches the refrigerant characteristics. Its chemical symbol is CH2FCF3. Theres no doubt that R12 refrigerant is one of the first compounds manufactured for the air conditioning and refrigeration world, but it had to be banned. El juny de 2017, el mateix grup va decidir crear un web deDoctor Who amb el mateix objectiu. I'll put the relay on for that. We ALWAYS want to know the pressure readings! With that said, I would source the TXV from another source such as NAPA just to avoid any problems. You can use the R134a retrofit capacity chart for this purpose. You may be just fine on oil - it depends on what compressor you have & how much oil you put in.A T/C is short for Thermocouple. Your decision could be made based on economics, environmental concerns, or both. R134a vs R12 refrigerant? The #1 question asked by NEW MEMBERS. Safety: R134a is safe to use as its non-flammable and cant explode. The original expansion valves work very well with R134a. Can I just use an adapter and save $200? With R-12, 30 is 28.4psi and 40 is 36.9psi, for a difference of 8.5psi. Therefore, the R12 refrigerant is illegal, and emitting it is illegal. Jun 19, 2007. I would suggest you do stay away from R-134a since with the hot gas bypass of your system (if it is to be just as the original) extremes of temperature and pressure will be very hard on your compressor and the rest of the system. They plug all the time. So if you car has a large amount of rubber hose, such as a 40 feet with the 911, then you will be re-charging the system often and that is expensive no matter which refrigerant you use.