A/C receiver difference between R12 and R134a? | NSX Prime As an example, let's say the R12 charge specification is listed at 2 lbs. Recovery & flushing is the only way out of an oil overcharge in your vehicle.B. difference between r12 and r134a expansion valve. 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. 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. After the system has been tested out it should be checked for leaks. Recharge the compressor with a/c ester oil and a tracer dye. 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). Given two identical vehicles, each with the same weighted amount of refrigerant, the vehicle with the R134a has the capability to remove more heat (measured in btus) from the vehicle than the same type of vehicle using the same amount of R12. Is that why expansion valves are specific to R12 or R134A? The name of the oil is Polyol Ester (POE). 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 . Can I just use an adapter and save $200? Thanks so much Bohica - you've save me many more hours of fruitless speculation. Hence, the effect of R12 on global warming is up to 10,000 times higher than carbon dioxide. Use strips of foam to couple the two heat exchangers if necessary.B. A/C systems designed to use R-12 will cool best when charged with R-12 refrigerant. My turn to LOL - greasiesel! R134a refrigerant fittings are different size. I have the original (R12) style expansion valve in the Maverick AC system. 42 (at best) w/ 134A in 2000 isuzu trooper. You do not want to exceed the systems high side recommendations. The general practice of charging the system with 15% less refrigerant adds to the thermal deficiency of R134a. R-12 - yellow R-134a - light blue R-22 - green R-402A - light brown (sand) R-402B - olive R-404A - orange R-407C - medium brown R-410A - rose R-507 - teal J Originally Posted by goldNSX. Or is there always room for improvement, the more the merrier. difference between r12 and r134a expansion valve Is there a difference between a R134a expansion valve and an R12 TXV? I'll report back on the aux fan on performance next. system of 0.33 TR and refrigerant used was R12. Though - the valve for a 1991 says R12 on it, and for a 1994, it says R-134a. In the automotive world, the replacement for R12 was R134a. Components Coils, Heaters, Motors, etc. The larger line at the expansion valve is the suction line. Mark Baker R-401b is the mixture by weight of 61% R22, 11% R-152a and 28% of R-124. Its chemical symbol is CH2FCF3. In no particular order, here's what I've found out regarding answering the questions posed so far:Fonebone - It is definitely an R4 compressor (they left the c off the front and the p off the end, i.e. I don't think it has any air dams or seals, I'll check to make sure. Heres some important advice Whenever you notice your R12 refrigerant is leaking, turn off all flames and open the doors so it can escape to the open atmosphere. In more serious, it could result in cardiac irregularities or death. 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. Yes it will work with either Refrigerant! Then at least I'd know really where I am on it. Paul:A 1983 240D should have a York compressor on an OEM system. 37 in 2005 tacoma, R134A. CONCLUSIONS The differences in the theoretical C.O.P.H calculated for R12 and R134a are consistent with values quoted in the literature. difference between r12 and r134a expansion valvewarning signs for a deteriorating patient with covid 19 infection 2022.07.03 18:36 18:36 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. With that said, I would source the TXV from another source such as NAPA just to avoid any problems. 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. Is there a graph? Automotive Replacement Expansion Valves & Parts; Industrial & Scientific; Customer Reviews. Even if the system leaks, repairing the leaks and recharging it with R-12 is usually the best repair alternative. 5. Condensers designed to release greater amounts of heat help to expel the greater amount of heat which R134a removes from the cars interior. What effect would it have on performance, if any? It has already been clearly stated that R12 is a chemical that damages the earths ozone layer and shouldnt be released into the environment no matter the circumstance. Therefore, its most suitable for both commercial and domestic environments. . The best replacement for R134a is R1234yf, while R12 refrigerant replacement was R134a. Skin contact: If the R134a (liquid) comes in contact with your skin, it could cause a burn. When the sensor detects the refrigerant leak the sniffers lights glow and the sniffer makes a noise. ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. If the system was upgraded by a professional it should have an upgrade sticker. leading to corrosion of expansion valves, capillary tube plugging, and compressor bearing . 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. The Main change in the system is the expansion valve. Can I use the one for the R-12? When the ambient air temps get above 80F the gauge readings can run a bit higher on the high side and lower on the low side when using R134a. I think so. Is there a difference between a R134a expansion valve and an R12 TXV? asia pacific stevie awards 2021. gin, amaretto cocktail. The reason is that the vehicles, for instance, manufactured currently configure the engine for R1234yf refrigerant, making no provision for replacement. 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. However, take note that R134a refrigerants are manufactured specifically for automotive air conditioners. R134a is NOT less efficient than R12 Actually R134a is more efficient. Your average garage that works on a/c on the side probably would not have this. Just had knee surgery yesterday, so I"M not exactly hopping around too well. An extra half ounce? At this point it is time to make an appointment with the a/c shop. 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. On this website we are addressing only R134a and not other suggested drop in replacements. 3 ounces? ThanksPaul -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. we convert older systems where i work all the time and they work fine. Since there is only about a 10% difference between R-12 and R-134a, the expansion valve being self-compensating really doesn't make that much difference. If there is a resource I should read first to save you time, let me know. difference between r12 and r134a expansion valve. difference between r12 and r134a expansion valve 1.5 ounces - hmmm. look at the difference! If you're getting a R134a compressor, might as well finish the job - replace the receiver/dryer, flush everything else, and convert to R134a anyhow. Get to the point where I can walk without crutches2. Thanks again. PDF COMPARISON OF Rl34a AND R12 REFRIGERANTS IN A VAPOUR - AIVC What is needed? It didn't seem too dirty though - I don't think it is the problem, but I could be wrong. Instead, top off R12 with R134a refrigerant. Besides, you have a greaseisel. Nick, I hear you - there maybe nothing to do here. And I lied about the compressor switches on this car - there are 2 switches on the drier - a temp and a pressure switch. The compressors used by refrigeration plants to compress gas require oil to help lubricate its moving parts. Discussion in 'Technical' started by Jsarnold, May 25, 2012. Do I leave the orignal condensor in, etc?Thanks. This drop can affect energy consumption since the plant will operate for a longer period or a larger plant will have to be installed. This is because R134a. difference between r12 and r134a expansion valve At 2000rpm, windows open, highest fan, hi pressure stabilized at 225 psi, low 25psi.Ambient 81F, vent 61F. 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? 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. Quick View. difference between r12 and r134a expansion valve Temp switch works the aux fan. -------------------------"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." I don't want to be chasing ghosts. difference between r12 and r134a expansion valve Why wait for 200f on the engine coolant to start the fan? The smoking question & vent airflow indicate that the evaporator is fairly clean - and you are aware of the importance of that.The heater valve stops the flow, but there is always some conduction heating. I dont know why the cost difference between compressors is so huge, though. The sticker typically has a place to note the amount of refrigerant used, the type of oil and amount of oil, the technicians sign off or name and the date of the conversion. The adjusted tension of this spring is the determining factor in the opening and closing of the expansion valve. I put one in my old daily driver '79 Chevy tank (r-12), and it really made a difference. The experimental values of C.O.P.H obtained with the R134a/ester charge were 20.2% The only material difference between automotive A/C and a window A/C unit or refrigerator is that in the home application, the components are all inside the same rectangular box, but in the automotive application, the components are distributed throughout the car. About four or five years ago, I guy with an MB came here with the same problem, that tread was over six pages long. But some types of PAG do not mix well with the old residual R12 mineral oil left in the system components whereas ester does mix very well. 2) Frost on the Vents. Flushed, vacuumed etc. The difference really shows up on the high side. 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 aux fan seems to be working fine - it switches on occassionally. Use a drop light in the engine bay, and check the air path from the front of the car at night. 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 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. -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. If you you dont have the free time to play then you are better off to pay a technician. There is only a temperature switch on these cars as far as I recall, and it just switches on the aux fan. Even though their common major function is to cool the system, they have many differences. Above this temperature, the saturation pressure of R134a is higher than that of R12; below, it is lower. 4) Repeat step 2, making sure it will fit. Warning: "continue" targeting switch is equivalent to "break".Did you mean to use "continue 2"? Replied by Rich928 on topic R12 or R134a. Some say that a chemical reaction can harm the A/C very badly as R134a reacts with mineral oil in some way. Edited: Sat July 14, 2007 at 10:22 PM by fonebone. I'm putting r12 back in my system, but all of the valves I can for the application (1990 jeep grand wagoneer) say r134a on them. R12 to 134A conversion. | Allpar Forums The catalytic converter is an essential component of your car's emission system that helps save the environment from harmful emissions. I found that in the..Maxposition on the control it will have the compressor running all the time. Hmmmm. It's best to determine on a case-by-case basis while monitoring system pressures and output air temperature. The condensor airflow drops off as the fan clutch dies slowly. However, it was found to be a very bad gas for the environment. Putting R12 into a R134 vehicle | AnandTech Forums: Technology It is made up of carbon, hydrogen, and fluorine. 4.R404A R134a increased mass transfer resistance to reduce the transmission chamber heat coefficient, while R507 heat transfer coefficient is higher than R404A. This is a great space to write long text about your company and your services. You do not however need to replace all the o-rings or seals for a simple conversion, it is simply a logical thing to do when and if the time comes to work or replace certain components because of age issues. But as there's not a big difference, people say you can suffice with either. 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. A/C Expansion Valve Replacement Cost. Questions About Becoming A Professional Member? The R134a compressor has a 1/8" step in on the high side port. After the initial charge the system is then tweeked : you determine the optimum amount of refrigerant to match your system by monitoring the a/c outlet vent temperature and the high side pressure as you add or remove refrigerant. I'm also thinking maybe I should go to R134 - it might work better with the right amount of oil and the correct expansion valve. Do a pre-inspection and then Evacuate (vacuum down) the system, the longer the evacuation the better but there is a point of diminishing return, 2-3 hours is generally very good. and recharged with mineral oil and 2.2 lbs R12. Thread starter goldNSX; Start date 1 August 2009; Tagged . Are r12 and r134 fittings different? The expansion valve is designed so that the temperature of the refrigerant at the evaporator outlet must have 8 to 12F (4 to 7C) of superheat before more refrigerant is allowed to enter the evaporator. Fitting a PF condensor is not rocket science, but it requires some planning. One thing at a time here, and slowly, the knee is not up to jumping around like I used to at the moment. 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. Replace the drier with a drier that has a desiccant that is R134a compatible, use new R134a o-rings. The value of carbon dioxide is 1. Where would I get some basic info on it, I know nothing about it. Jun 19, 2007. The major reason for the replacement of R12 with R134a was to curb future greenhouse effects. The higher the ambient temperature the higher the high side pressure. And yes - expansion valves sometimes need replacing if they are sticky - but a proper AC flush should eliminate the need for a new one if it's already in good condition. So to keep things simple and to avoid controversy and politics we have R134a. Took me a while to figure that one out, and how to say that. The larger fitting goes on the discharge port and the smaller fitting goes on the suction line or compressor inlet / suction port. Osuagwu Solomon is a certified mechanic with over a decade of experience in the mechanic garage, and he has over five years of experience in the writing industry. Formula: (R12 Charge Specification x 0.9) - 0.25 lbs. I have one can left, so maybe a plan can be made. I recommend replacing the expansion valve when you do the swap. -------------------------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! It is perhaps possible to locate a unit with a company that purchases close out or distressed merchandise. R12 was once used in many air conditioning units as a refrigerant or cooling agent. R404a is a zeotropic blend with a temp glide , because of the mixture of 2 or more refrigerants. If your cars system has a sufficient condenser design and air flow to expel the greater amount of heat extracted by R134a, then by all means you should convert over when the time comes. R404a for freezing of product. Any suggestions, or do you need to know the hi/lo readings? We've updated our forums!Click here to visit the new forum, Year: 1991Make: Jaguar Model: XJ6Engine Size: 4.0. Also called the orifice tube. By noting the ambient temperature you can look up what the preferred high side pressure should be. It won't be optimal, though.On some/many valves, you can adjust them, but that might make matters worse unless you really know what you're doing (which I don't!).RegardsGeorge. 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 chemical composition of R12 and R134a differ. You'll want the expansion valve matched to whatever refrigerant you're using. Kommentare . might be due to charge or different compressor and age. For R12, its mineral oil. And, unfortunately a small high side pressure gauge on a short hose. 3) A TXV optimized for 134a will be ok with R12. I would not do a 134a conversion without a PF condensor. It is also used in automotive car conditioning and the plastic industry. difference between r12 and r134a expansion valve. Related products. In a car ac, using this type of freon 20 years ago was difficult. Safety: R134a is safe to use as its non-flammable and cant explode. difference between r12 and r134a expansion valve But, what is considered a good temperature differential across the condensor? 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. A/C receiver difference between R12 and R134a? R12 can move more heat than r134 so when it isn't very hot and the system isn't maxed out you wont be able to tell the difference but when its 110 out and the inside is 140 R12 will cool the cabin temp faster. And by matching the correct amount of R134a to use in a given vehicle, correcting the superheat of the expansion valve (if necessary), you can in some manner nearly balance or match the amount of heat drawn out by the evaporator and released by the condenser. 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!) George Bray on Wed August 31, 2005 5:03 PM I believe the optimum supercool setting will vary slightly between an expansion valve for an R12, as compared to R134a, system. Since the hose is the stock hose, you cannot tell what refrigerant is inside. The general practice of charging the system with 15% less refrigerant adds to the thermal deficiency of R134a. If you have the work done, be sure you find a true "A/C" shop that can make up lines. A discussion of the relationship between valve capacities and superheat set-tings can be found in Bulletin 10-9. The crossover point is approximately at 64F. SO here's my question. Below are the major differences between R134a and R12: Chemistry The chemical composition of R12 and R134a differ. Thus, when the system is running, condensing the CO2 is not a problem. The newer valves and switches will work with both refrigerants. At 40, it is 35psi, which is a difference of 8.9psi. What is usually sniffed are all the connections in the system: hoses and compressor, condenser, drier, expansion valve and evaporator fittings. Replacement expansion valve for R134a or R12 A/C refrigerants, with O-ring connections. So, instead of using R12, other better options include R401b, R134a, R401a, etc. Also, they are mostly used in refrigeration and automotive air conditioning systems. This kit comes complete with Expansion valve, o-ring kit, and 1ft. As for R134a and R1234yf, theres no room for conversion. Disconnect the two hose lines to the compressor, protect the ends from getting dirty. 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. Rules governing changing from the former to the latter differ between countries. Just leave it alone for now. Paul -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. It can be used applications like walk-in coolers, food and dairy display cases, domestic refrigerators, and beverage dispensers and vending machines. The ARPA Zone/Open Membership Discussion Forums. The global warming potential measures the amount of heat trapped by any gas compared to the amount of heat trapped by the same amount of carbon dioxide. I'm thinking I might have put too much oil in the system - everywhere i read had a different amount - the manufacturer of the compressor, the MB factory service manual, online forums. If you have a perfectly operating system using R12 you do not have to drop what you are doing and convert to R134a. Accessories Pumps, Cooling Towers, Evap Condensers, etc, Components Valves, Motors, Condensers, Evaporators, etc, Duct Systems Design, Installation & Practice, Piping Systems Design, Installation & Practice, Control System Design, Installation & Practice, Pro's Forum: National Electrical Code (NEC), Pro's Forum: Calculations & Electrical Theory, Pro's Forum: Electrical Business & Marketing. And no, you cannot "drain' excess oil out. R134a and water have the same abilities to change the state but R134a can do this more rapidly and at a much lower temperature than water. Operating Pressure/Temperature Differences The pressure/temperature curves for R-1234yf and R-134a are very similar. R12 is heavier than R134a and has smaller molecules. difference between r12 and r134a expansion valve. The exact amount will vary with each car. Most importantly, the oil used in the plant must always be compatible with the refrigerant used. A. Pressure/temperature table for R12, R134a, and R513A is shown in Figure 1. . There are three different refrigerants officially sanctioned by the EPA for automotive usage: r-12, r-. Rxmechanic.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for website owners to earn advertising fees by advertising and linking to Amazon.com. 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. R12 systems used mineral oil, but unfortunately mineral oil doesn't dissolve in R134a. R12 or R134a - 928 Owners Club Forum . Catalog E-1, Thermostatic & Automatic Expansion Valves / Page 1 Table of Contents . Stay home and grill your own steaks and stir your own martini. Talk about what services you provide. It runs between the condenser outlet, receiver/drier unit and expansion valve at the firewall. R12 is highly destructive to the earths ozone layer. R134a was selected as a replacement refrigerant for R12 because R12 contains chlorine and has a major effect to ozone layer depletion.