The pressure at low temperatures is nearly the same between 12 and 134a. If your a/c system is empty/low on refrigerant, if your system has a leak or if you need to open the system, then now is the time to decide which refrigerant you want to use. Then at least I'd know really where I am on it. Until 1995, most cars with air conditioning used R-12 Freon refrigerant which has shown to have an environmental impact. absorb by the evaporator to insure all liquid refrigerant entering the evaporator. Its chemical symbol is CCl2F2. Yes, this was a smokers car. The cure is to use the newer R134a compressors is sealing washers that are different thickness. Jun 17, 2011. Is there a difference between a R134a expansion valve and an R12 TXV? With the knowledge of the differences, youll be able to draw a comparison between R12 vs R134a efficiency. It slowly gets warmer and warmer in the car, even at highway speeds. 30 deg is pretty coldSystems generally run between 40 and 43 deg. Once you have replaced the OEM condensor with a PF unit, you will need to make custom hoses to mate with your OEM system. Formula: (R12 Charge Specification x 0.9) - 0.25 lbs. Later model cars that come with 134A will have 134A only connectors. Your decision could be made based on economics, environmental concerns, or both. But as there's not a big difference, people say you can suffice with either. A/C Expansion Valve Replacement Cost. 2001-2023 Griffiths Technical Inc. All Rights Reserved. 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). I know this is bad, etc, and deposits on the metal can act as insulators. If he is not in the garage fixing challenging mechanical problems, he is writing automotive repair guides, buyers guides, and car and tools comparisons. R134a compressors are substituted as new to retrofit the R12 system compressor part numbers with different height sealing washers. Hmmmm. Could that be screwing up the systems performance?Anyway, when I installed the system, the new TXV (is that short for expansion valve?) |. 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 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. Also, they are mostly used in refrigeration and automotive air conditioning systems. Very nice! At least you do not have 16 ounces in there ( yup seen it before).For now, straighten all of the fins that you can, clean the condensor well, and re-test with the aux fan running. A. Pressure/temperature plot of R134a vs. R12 is shown in figure 1. Bottom line, R134a simply doesn't cool as well as R12. Spray it deep, and let it sit for a few minutes. The system has been previously converted to R-134a. R134a is called tetrafluoroethane (HFC). 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 am ordering new parts, and planning to convert my system to R-134a. Is the information not applicable to the old Pantera system? 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. Stay home and grill your own steaks and stir your own martini. Be sure to test @ 1500 to 2000 engine rpm, and record the ambient temp as well. Then when it is switched off for a few minutes and then back on, the air cools again. 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. Post photos, respond to polls and access other special features. The only difference I can imagine would be the recharge connection. Failure to abide by the EPA regulations can result in expensive fines for either you or your service technician. 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 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. Trinary Pressure Switch $ 39.99. -The amount of R-134a needed will typically be 80-90% of the R-12 charge. A slow loss of cooling at city speeds is usually related to condensor capacity & airflow issues. difference between r12 and r134a expansion valve why is miles raney not on homestead rescue June 21, 2022. manila mayor candidates 2022 R12 is heavier than R134a and has smaller molecules. There are significant differences between R12, R134a, and R513A, which must be considered when handling, processing, applying, or retrofitting with these refrigerants. I think so. Use a drop light in the engine bay, and check the air path from the front of the car at night. american sniper longest shot; how to adjust sunsetter awning arms; pastor jeremy roberts texas. Make sure to wear safety gloves, goggles, and shoes when theres a possibility of exposure to the chemical (R134a). R12 and R134 are of different chemistry. You do not need to replace every o-ring in the system, but if you happen to open a connection that has an o-ring you should replace the old o-ring with one that is compatible with R134a and lubricate the o-ring with ac oil. Replied by Rich928 on topic R12 or R134a. But, if your old compressor has lock-up or if your current expansion valve is not functional it would wise to replace the expansion valve with a valve designed for R134a. Your average garage that works on a/c on the side probably would not have this. In practice this means that the car can overheat and the aux fan will stay off! Thus, when the system is running, condensing the CO2 is not a problem. Neuro spine Super Speciality Clinic - Above Apollo Pharmacy, Bangarpet Circle, Kolar - Bangarpet Road, Kolar Town. 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. R1234yf. Is there a difference between a R134a expansion valve and an R12 TXV? An extra half ounce? 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. Using R134a requires that Polyolester (POE) lubricant must be used in the compressor. Thomas Jefferson, Thanks,OK, I'm starting to feel a little better about it. Moreso, it had been banned. This would be a custom install, there is no "drop-in" condensor upgrade for that car.Check for proper fan operation, and clean the air path on both the condensor & radiator. 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. ). 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). Whenever its exposed to the environment, it changes to a gas. Recomanem consultar les pgines web de Xarxa Catal per veure tota la nostra oferta. 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!) This works when the R12 charge specification is listed in pounds. Blows pretty hard on full. Nice to use new gadgets! Electric fans do wear out. Comparatively, larger R134a molecules should take more space, and a smaller amount might be required. 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. You either get a system that will function well with R1234yf or get any other type. 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. = R134a Charge Level. All pre-97 XJs use systems with the same basic operating principle, although the parts do change a bit. We, the Rxmechanic team, have presented a well-detailed comparison of R134a vs. R12. and recharged with mineral oil and 2.2 lbs R12. Can I just use an adapter and save $200? As R134A refrigerant has different operating characteristics and pressures this valve is not necesssry. Big . 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. The difference between R12 and r134a is the BTU carrying capability. Is checking the temperature of the in and out of the condensor not the easiest way to tell if it is doing a good job or not? Temp switch works the aux fan. link to How to cut off a Catalytic Converter. 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. Not going to mess up your 'do, but you can feel it. 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. -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. Thanks so much Bohica - you've save me many more hours of fruitless speculation. -------------------------"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." Mark Baker R-401b is the mixture by weight of 61% R22, 11% R-152a and 28% of R-124. The cure is to use the newer R134a compressors is sealing washers that are different thickness. Are you sure you have an R4? and feeds it through an expansion valve. Gain access to our free AOP (Ask a Professional) Section to get real answers for your questions. BTW, I use a stick thermo in the vents and the laser on the condenser. $21 . The experimental values of C.O.P.H obtained with the R134a/ester charge were 20.2% Stability: RR12 doesnt disintegrate even under extreme operating conditions. 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. Concentration level: The R134a vapor dilutes the oxygen concentration in the air to a low level, thereby causing harm. 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. Then again, there are two different expansion valves. Inasmuch as R134a has a global warming potential thats over 1000 times more threatening than carbon dioxide, its better than R12. I just got some hi/lo side gauges so I'm going to take readings, if they are needed. This allows the refrigerant in the condenser to be void of oil particles. 5) A/C System Failure. R134a. Here are the basics for converting a system that does not have a charge of R12, its empty. Thread starter goldNSX; Start date 1 August 2009; Tagged . On this website we are addressing only R134a and not other suggested drop in replacements. Is it exponential, squared? Disconnect the two hose lines to the compressor, protect the ends from getting dirty. If the system was upgraded by a professional it should have an upgrade sticker. For those of you who are considering what the cost is for R12 you can think of it this way: Dont go out to dinner this weekend. system of 0.33 TR and refrigerant used was R12. The substitute that we used for R-12 was the new HFC called R-134a. After the optimum refrigerant charge is determined the car should be test driven to check for performance of the system. This is a great space to write long text about your company and your services. I'm going to check the condensor is way clean too. You can use this space to go into a little more detail about your company. When I compare parts, 93 uses one part number and 94 has a different part number. These efforts to balance the system can not be realized if there are problems within the a/c system, such as: poor performing compressor, dirty condenser or poor air flow through the condenser, malfunctioning expansion valve, water or air in the system, improperly operating fresh air or heat input in the climate-air mixing system. The problem with these so called drop in replacements is that to properly handle them you may need dedicated equipment to identify the gas and evacuate it for proper disposal. 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. What is needed? If you find any of these conditions you will want to liquid flush (with dedicated AC flush solution) all the lines, condensers, evaporator (remove the expansion valve) before you proceed further. Anyone know what happens when an R12 expansion valve is used in a system charged with R134A? Answer: OK, I'll bite. Expansion Valve. As for R134a and R1234yf, theres no room for conversion. Is that reasonable?Vent airflow is good, I think. . Operating Pressure/Temperature Differences The pressure/temperature curves for R-1234yf and R-134a are very similar. What is a T/C?4. Super heats are so close, it should not be a major concern.-------------------------The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government. With the A/c off hi and lo were both at 105psi. Carefully study the chart and compare the following: To a large extent, the choice is up to you. 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. This drop can affect energy consumption since the plant will operate for a longer period or a larger plant will have to be installed. Also, it can be used with all types of compressors. R134a has a smaller molecule than R12 so R134a will leak out sooner than R12. Crap! Swapping the components isnt a herculean task, but recharging the AC is a challenge. The aux fan seems to be working fine - it switches on occassionally. I'm doing one thing at a time so I know what the cause was. 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. Is there a difference in the expansion valve for R12 as opposed to R-134a? The larger line at the expansion valve is the suction line. I could easily be over at least 2 - 3 ounces over on the oil. I put one in my old daily driver '79 Chevy tank (r-12), and it really made a difference. R12 Expansion Valve = 201 830 06 84 R134A Expansion Valve = 201 830 04 84 Is there a difference after all? I'm just trying to help you avoid headaches in the long run. The exact amount will vary with each car. That would be the "black death" syndrome. 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. With R12 you use to check to see if the site glass was full, if it had bubbles it meant you had a low charge. By: james smith underoath; Comments: 0 . Generally the system will be initially charged with approximately 80% to 85% of the original amount of R12, using R134a. For instance at 25 F the pressure of R-12 is 24.6 PSI and the pressure of R-134a is 22.1 PSI. Since the hose is the stock hose, you cannot tell what refrigerant is inside. To ensure the right charge, you must fill the new system with between 75 and 85% of the factory-set capacity for optimal cooling. Replace the drier with a drier that has a desiccant that is R134a compatible, use new R134a o-rings. . 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). 5. RULES for AOP - Owner Assistance and Contractors, Energy Efficiency and Building Performance Discussion NEW, Carnak Zone/Locked Areas - For Professional Member Only, How To Become a Pro and Rules For Pro Members, Pro Forum: Refrigerants and EPA regulations **NEW, Pro Forum: Residential Refrigeration and Appliances **NEW, Pro Forum: Equipment Recalls and Bulletins **NEW, Pro's Forum: Building Science Discussions, Educational Forums - Open for all in the industry, Welcome to HVAC-Talk's Educational Forums, How to Submit Links, Articles and Quiz Questions, Frequently Asked Questions About Submissions, Physics, Thermodynamics, Fluid Flow and Combustion, Educational, Training & Reference Information, Manufacturer's Technical Information Links, Electrical Theory, Circuits and Electronics, HVACR Equipment, Components & Accessories, Accessories Humidifiers, Air Cleaners, HRUs, Fans, Filters, etc. I recommend replacing the expansion valve when you do the swap. R134a is called tetrafluoroethane (HFC). Before R12 was replaced with R134a in 1995, it was mostly used in trucks and cars. When the temperature is reduced to-7C or below, the plants ability to cool the airdrops significantly. R134a was selected as a replacement refrigerant for R12 because R12 contains chlorine and has a major effect to ozone layer depletion. 10,000BTU conduction heating? Can I use the one for the R-12? Only show this user. 4.3 out of 5 stars 491. ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. difference between r12 and r134a expansion valve. Hope this helps. It would make a big difference at idle ,in traffic!! It is a haloalkane and hydrofluorocarbon (HFC) refrigerant that has thermodynamic properties, potential global warming for one hundred years, and insignificant ozone depletion. For example, if your system originally had 36 ounces of R12 then you multiply that by .80 and you have 29 ounce of R134a. I'm not sure. Do I leave the orignal condensor in, etc?Thanks. The difference between R12 and R134a TEV (exp valves) is primarily the 'superheat'. Still, I have some simple green, so may as well give it a go. Its chemical symbol is CCl2F2. The analysis focuses on Coefficient of Performance for . Then again, there are two different expansion valves. Its among the greenhouse gases and will keep adding the current problem of heat not leaving the earths atmosphere. We are an automotive mechanic blog that helps mechanics and car users to find the most recent and accurate technical and repair information for their cars. Gnats & mosquitos will clog deep. It is mixed with the freon for the most part, and does accumulate in all components in small amounts. Get to the point where I can walk without crutches2. They can be mounted quite easy,and there is a mounting kit that helps to hang it. . -------------------------"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." Yes, the 50F diff (160-110F) on the condenser was at idle, and ambient was about 90F. That way I will have reduced the oil by about 1/3 (assuming the oil is mixed evenly through the system). R12, on the other hand, is called chlorofluorocarbon (CFC). Debug the condensor (I am a computer nerd after all!)3. But R22 is almost equally damaging. 1.5 ounces - hmmm. A Lot of the fins are bent, especially at the top. What was the ambient when you took that reading?Jumpering the aux fan is a common thing here in the desert. 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. All fans must work at 100% of the OEM rating. If not, you just don't know unless a test is performed. 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. If you you dont have the free time to play then you are better off to pay a technician. The pressure at low temperatures is nearly the same between 12 and 134a. We say generally because the vehicle manufacturer may have a formula already worked out for the R134a conversion process. This means that it has a high potential of causing depletion to the ozone layer. 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. gital control scheme. It is made up of carbon, hydrogen, and fluorine. I think the way to go here is1. What is the refrigerant property involved that has caused this? in /nfs/c05/h04/mnt/113983/domains/toragrafix.com/html/wp-content . Different correction factors are applied to other refrigerants. I don't recall all the details, but starts off with the largest parallel flow condenser and improved fans. The only mechanical differences between an R12 system and an R134a system are that R134a systems typically have larger condensers and more powerful compressors. 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. Besides, its technology has been tested and trusted. With that said, I would source the TXV from another source such as NAPA just to avoid any problems. The good thing is that after you convert to R134 you can top off the system easily and cheaply. CR4P). If you still find it difficult to use R134a in a home AC system, you can check out a comparison of R12 vs R134a fittings to know the refrigerant that best fits the AC system. Bad Car A/C Expansion Valve Symptoms. Why wait for 200f on the engine coolant to start the fan? Lets take you through the advantages, disadvantages, and differences of these two refrigerants a detailed comparison including R12 vs R134a performance.