As illustrated in the chart below, the curves below run together nearly throughout the curve, only slightly breaking paths at around 250 psig/150 degrees and above Flammability/Safety R-1234yf has been designated as MILDLY flammable. In sum, R12 has done more bad than good. Please enter a valid email address for yourself. Failure to abide by the EPA regulations can result in expensive fines for either you or your service technician. There are three different refrigerants officially sanctioned by the EPA for automotive usage: r-12, r-. asia pacific stevie awards 2021. gin, amaretto cocktail. 5. This chart has a column of ambient (outside) air temperatures on one side and a corresponding range of high side pressures on the other side. To bless the system the technician should attach a R134a sticker somewhere in the engine compartment to note the car is using R134a. Production of R12 ceased in 1996, although it can still be reclaimed, purified, and resold, and small cans of New Old Stock R12 are still widely available on eBay and Craigslist. Break out the new gauges and measure hi and lo at 1500rpm, and do the Merc FSM test to see how we're doing performance wise. Statisicaly your friend was lucky. We've updated our forums!Click here to visit the new forum, Year: 1983Make: MercedesModel: 240DEngine Size: 2.4Refrigerant Type: R12Ambient Temp: 90Pressure Low: 35Pressure High: ?Country of Origin: United States, Hi, this is my first post, so please take it easy on the noob. And, unfortunately a small high side pressure gauge on a short hose. Post photos, respond to polls and access other special features. Consider using the newer valve, even with 134a stamped on the valve. The flammables have hydrocarbons. Depending on which circuit diagram fits your car (cough, no vin list exists) you have either one or two switches controlling the aux fan. Well, I'm not sure it is 'fine' - it doesn't cool very well in 95F weather. -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. There are two hoses listed, R-12 64-53-1-377-821 for $72.50, and R-134a 64-53-8-391-051 fro $262.50. The problem with not being an expert is that you don't know what is important and what's not. Carefully study the chart and compare the following: To a large extent, the choice is up to you. Boiling Point: R134a refrigerants boiling point is -26.3C (-15.34F). With that said, I would source the TXV from another source such as NAPA just to avoid any problems. Bookmarks: Digg; del . You should keep in mind that recharging your air conditioner improperly could result in more serious damage. It will work and there will be very little, in any difference in performance.As Chick stated, the difference is only the gas used in the sensor tube. For instance at 25 F the pressure of R-12 is 24.6 PSI and the pressure of R-134a is 22.1 PSI. Should I do the test again with the the aux fan jumpered? That switch should close @ 52c. The ARPA Zone/Open Membership Discussion Forums. Nevertheless, if your application is configured only for R12, then you can use it or consider replacing the applications engine. When ever possible you should ask the technician to note the same information on your repair bill and keep a copy in your glove box for future reference. It is made up of carbon, hydrogen, and fluorine. The system has been previously converted to R-134a. Also called the orifice tube. This is an electronic tool that sucks in air through a tube and across a sensor. CR4P). 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). R-401b is the mixture by weight of 61% R22, 11% R-152a and 28% of R-124. This allows the refrigerant in the condenser to be void of oil particles. R12 and R22 are both now banned by the EPA in the United States. They plug all the time. 2022 nba 2k22 starting a fashion label signing the designer, a difference between r12 and r134a expansion valve, 2020 white paper of the church of pentecost, Chime Mobile Check Deposit Funds Availability, Why Does James Kill Donald In The Vanishing, nba 2k22 starting a fashion label signing the designer. With R134a you do not rely on the site glass. 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. As for R134a and R1234yf, theres no room for conversion. Is there a difference between a R134a expansion valve and an R12 TXV? Hope this helps. Is there a source of valves by, say, eaton number? Expansion valves are an active device, they regulate the flow of refrigerant to the evaporator depending on evaporator temperature. R12 is simply too expensive for a 25+ year old A/C system. Components Coils, Heaters, Motors, etc. And I already have so much time and money in this a/c project that I REFUSE to cut any corners as small as a TEV.It doesn't help that most people in the business (at least that I come in contact with, present company excluded, of course!) In practice this means that the car can overheat and the aux fan will stay off! R12 Expansion Valve = 201 830 06 84 R134A Expansion Valve = 201 830 04 84 Is there a difference after all? Get to the point where I can walk without crutches2. Not going to mess up your 'do, but you can feel it. This drop can affect energy consumption since the plant will operate for a longer period or a larger plant will have to be installed. Just had knee surgery yesterday, so I"M not exactly hopping around too well. BTW, I use a stick thermo in the vents and the laser on the condenser. Don't like the sound of custom parallel condensor. Crap! However, the supply houses don't indicate a difference. The typical scenario here is when the car owner buys an inexpensive retro-fit kit from the local auto parts store. 1.5 ounces - hmmm. Still, I have some simple green, so may as well give it a go. Yes, the 50F diff (160-110F) on the condenser was at idle, and ambient was about 90F. 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. R134a compressors are substituted as new to retrofit the R12 system compressor part numbers with different height sealing washers. ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. 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. For R12, its mineral oil. The common problem when converting from R12 to R134a is lack of knowledge or equipment. Compatible with multiple applications: The major reason for the introduction of R134a was to replace R12, so it functions perfectly in the same range of applications like rotary, screw, and centrifugal compressors for air conditioning and refrigeration. So I probably put the highest suggested amount in to be safe. Is there a graph? 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. 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. 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. Temp switch works the aux fan. Debug the condensor (I am a computer nerd after all!)3. But I don't want to waste your time. The cure is to use the newer R134a compressors is sealing washers that are different thickness. I had a 1991 BMW switched to 134a by just changing the low pressure charging valve, flushing and refilling with 134 (maybe with 10% . . But R22 is almost equally damaging. ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. You can buy bulk hose, and the proper fittings, then have them crimped off the vehicle.Be sure that no air bypasses the new condensor on the way to the radiator. R404a is a zeotropic blend with a temp glide , because of the mixture of 2 or more refrigerants. That's a lot isn't it? I think so. It slowly gets warmer and warmer in the car, even at highway speeds. R134a has an ozone depletion potential of 0, implying that it has a slight effect on the ozone layer. Agram a retevis rt22 password i bastrop county district clerk records el material que oferim als nostres webs. R12 was once used in many air conditioning units as a refrigerant or cooling agent. Mark Baker R-401b is the mixture by weight of 61% R22, 11% R-152a and 28% of R-124. Unfortunately, the oil only mixes with the refrigerant as a liquid. The global warming potential of R134a is 1430. Refrigerators generally utilize R22, R32, or 410A-based coolants as their cooling agent. We suggest dumping the old refrigerant oil in a clean container and inspect the oil for sludge or waxing (old oil that has gelled) and contamination (metal particles). Pray I can let some oil out of the compressor without losing my precious R12. He started writing automotive articles to share his garage experience with car enthusiasts and armature mechanics. Typically 5 to 6 ounces of a/c oil is adequate but this may vary depending upon the car. Some say that a chemical reaction can harm the A/C very badly as R134a reacts with mineral oil in some way. Best for varieties of operating conditions: Its boiling point is -21.6 Celsius. This means that it has a high potential of causing depletion to the ozone layer. The butylcellusolve or the citrus solvent will dissolve the carcass in a few minutes. Use strips of foam to couple the two heat exchangers if necessary.B. In most cases, the systems used have varied components, designs, and service ports. It cycles on off in med (or low for that matter)Gotta tell ya. I don't have the FSM matrix handy for that 123.123, but a 123.133 shows a test rpm of 2,000 - and vent temps between 54f & 66f at 91f to 95f ambient. If the system was upgraded by a professional it should have an upgrade sticker. 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. Also, it can be used with all types of compressors. Large temperature difference between expansion valve inlet and outlet oReplace expansion valve Air . As R134A refrigerant has different operating characteristics and pressures this valve is not necesssry. might be due to charge or different compressor and age. Can I order a valve based on the original eaton number? I had to vaccum the system for 2 hours and recharge 4 oz of PAG oil plus 36 oz of 134A freon (3 cans). -------------------------"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." Lets take you through the advantages, disadvantages, and differences of these two refrigerants a detailed comparison including R12 vs R134a performance. The larger fitting goes on the discharge port and the smaller fitting goes on the suction line or compressor inlet / suction port. compressor, condenser, evaporator and expansion valve are specifically designed for use with R134a. 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. Took me a while to figure that one out, and how to say that. A thermostatic expansion valve (TXV) (see Figure 1) is a refrigeration and air conditioning throttling device that controls the amount of refrigerant liquid injected into a system's evaporatorbased on the evaporator outlet temperature and pressurecalled the superheat. On the other hand, R12 has a global warming potential of 10,910. Its cylinders are colored white. Is there a difference in the expansion valve for R12 as opposed to R-134a? Remember, being aluminum, they lower the temps better, and do not pass off as much heat to the radiator, which then makes it's job easier and lowers underhood temps (besides lowering vent temps inside the car). Any ideas from the info above? If the water valve is not closing all the way you will have re-heating of the cabin air.The cabin blower was not exactly a powerhouse - it was rated at 200w. . The pressure at low temperatures is nearly the same between 12 and 134a. Sense ells no existirem. The system has been previously converted to R-134a. If there is a resource I should read first to save you time, let me know. Where would I get some basic info on it, I know nothing about it. What is needed? Some compressor manufacturers or OEMs suggest PAG type oil for R134a. and recharged with mineral oil and 2.2 lbs R12. The mechanical fan & clutch should be checked as well. -The amount of R-134a needed will typically be 80-90% of the R-12 charge. When the temperature is reduced to-7C or below, the plants ability to cool the airdrops significantly. Operating Pressure/Temperature Differences The pressure/temperature curves for R-1234yf and R-134a are very similar. Generally, the new amount is 75-85% of the quantity advised by the manufacturer. Generally the system will be initially charged with approximately 80% to 85% of the original amount of R12, using R134a. R134a requires a different oil. In short, NO! The approval is very legal one, governed by the U.S. EPA. The Main change in the system is the expansion valve. VerticalScope Inc. All Rights Reserved. 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. had writing on the side that said R134a. Replace the drier with a drier that has a desiccant that is R134a compatible, use new R134a o-rings. It runs between the condenser outlet, receiver/drier unit and expansion valve at the firewall. 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 . The Wikipedia explanation for expansions valves cited in Frank's thread says that the gas inside the bulb in the metering valve is the same as the refrigerant in the system. Also, R134a cylinders are light-blue in color.