A discussion of the relationship between valve capacities and superheat set-tings can be found in Bulletin 10-9. 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. AFAIK, there is no clutch on the engine fan on the 240D. How dumb!I will jumper the aux fan and redo the test. The oil used in R12 and R134a are different and not compatible. Took me a while to figure that one out, and how to say that. -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. difference between r12 and r134a expansion valvewarning signs for a deteriorating patient with covid 19 infection 2022.07.03 18:36 18:36 difference between r12 and r134a expansion valve. There are R134a specific valves that operate at a slightly different pressure, but not for any "old" automotive application that I'm aware of. 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. With the knowledge of the differences, youll be able to draw a comparison between R12 vs R134a efficiency. Looks like a couple of things happening here1) 80's vintage Eurocars were not "meat lockers". If you have a York, and it is equipped with service valves, you can check & adjust the oil level without discharging the system. The larger fitting goes on the discharge port and the smaller fitting goes on the suction line or compressor inlet / suction port. The only difference I can imagine would be the recharge connection. System has been working fine for a year. Usually, mechanics charge around $200 for conversion. 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. 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. The aux fan didn't switch on though and I didn't check the high side temperature. AC R12 to R134A Conversion | MR2 Owners Club Forum Failure to abide by the EPA regulations can result in expensive fines for either you or your service technician. Thanks so much Bohica - you've save me many more hours of fruitless speculation. The higher the ambient temperature the higher the high side pressure. 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. Can I order a valve based on the original eaton number? leading to corrosion of expansion valves, capillary tube plugging, and compressor bearing . It is a haloalkane and hydrofluorocarbon (HFC) refrigerant that has thermodynamic properties, potential global warming for one hundred years, and insignificant ozone depletion. Its chemical symbol is CCl2F2. A Comparison Study of the Thermal Performance of R12 and 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. 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. american sniper longest shot; how to adjust sunsetter awning arms; pastor jeremy roberts texas. 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. R134a refrigerant is lighter than R12. "Howdy, Folks!" PDF R134a R513A - Tecumseh Products Therefore, its most suitable for both commercial and domestic environments. What effect would it have on performance, if any?At the moment, the ac is acting up - will work fine for about 15 minutes and then slowly the vent temperatures rise until the compressor switches off. The exact amount will vary with each car. The newer valves and switches will work with both refrigerants. and feeds it through an expansion valve. 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. Then, subtract that result by 0.25 pounds to get the proper amount of R134a charge. GWP is a measurement of Greenhouse Gases and their effect on Global Warming. A/C systems designed to use R-12 will cool best when charged with R-12 refrigerant. This refers to BTU's (heat) moved per pound of refrigerant moved. Then I'll put the ball valve in on the coolant and test it and see what we have. 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. This allows the refrigerant in the condenser to be void of oil particles. Thomas Jefferson, Thanks,OK, I'm starting to feel a little better about it. However, it was found to be a very bad gas for the environment. If the charge is low the compressor will cycle on/off in the max AC position. ThanksPaul -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a. 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. 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. link to How to cut off a Catalytic Converter. I have one can left, so maybe a plan can be made. El juny de 2017, el mateix grup va decidir crear un web deDoctor Who amb el mateix objectiu. sparkee said: Thanks for the Service Bulletin. Even though their common major function is to cool the system, they have many differences. An extra half ounce? For R12, its mineral oil. A/C R12 to R134a Conversion Success | IH8MUD Forum That's a lot isn't it? Is there a difference between a R134a expansion valve and an R12 TXV? R134a was selected as a replacement refrigerant for R12 because R12 contains chlorine and has a major effect to ozone layer depletion. 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. For instance at 25 F the pressure of R-12 is 24.6 PSI and the pressure of R-134a is 22.1 PSI. 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. I have the original (R12) style expansion valve in the Maverick AC system. They have no moving parts. difference between r12 and r134a expansion valve The substitute that we used for R-12 was the new HFC called R-134a. The approval is very legal one, governed by the U.S. EPA. 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. 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. Warning: "continue" targeting switch is equivalent to "break".Did you mean to use "continue 2"? The AC usually does not work at all. If liquid refrigerant were to exit the evaporator. 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. Disconnect the two hose lines to the compressor, protect the ends from getting dirty. Here are the basics for converting a system that does not have a charge of R12, its empty. With that said, I would source the TXV from another source such as NAPA just to avoid any problems. The cost of recharging the air conditioner is between $150 to $500. 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. It is made up of carbon, hydrogen, and fluorine. 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. Look deep into the fins. All fans must work at 100% of the OEM rating. 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. -------------------------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. 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. I could easily be over at least 2 - 3 ounces over on the oil. . Your old hoses of course will not fit. Hence, let us continue to fix it. Later model cars that come with 134A will have 134A only connectors. This is because R134a. The difference between R12 and R134a TEV (exp valves) is primarily the 'superheat'. #19. Generally you follow the refrigerant flow moving from connection to connection, component to component, and you sniff the a/c vents to check for evaporator leaks as well. R12, on the other hand, is called chlorofluorocarbon (CFC). Flushed, vacuumed etc. #13. Expansion Valve Differences R12 vs R134 - Automotive Air Conditioning 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. Before we mentioned that you can add approximately 5-6 ounces of ester oil to the compressor. 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. I'm doing one thing at a time so I know what the cause was. In cases such as this, the required capacity value of the expansion valve with R134a is reduced by 30% (correction factor 1.42). Hope this helps. R12 is simply too expensive for a 25+ year old A/C system. -------------------------"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." R134a and R12 are among the most popular types of refrigerants. SO here's my question. I don't want to be chasing ghosts. The global warming potential of R134a is 1430. R134a requires a different oil. The system has been previously converted to R-134a. 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. This drop can affect energy consumption since the plant will operate for a longer period or a larger plant will have to be installed. Discussion in 'Technical' started by Jsarnold, May 25, 2012. The MB chart shows 360 psi with R12 in some conditions. 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. Compressor. _____ 2012 E350 2006 Callaway SC560 . -------------------------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! Just because the radiator does not boil people assume that the cooling system is ok. I'm going to check the condensor is way clean too. 3 ounces? Yes it will work with either Refrigerant! 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. A/C receiver difference between R12 and R134a? There is more to check.The evaporator must be clean as well as the condensor - was this a smoker's car?You should check the water control valve for the heater core. I am ordering new parts, and planning to convert my system to R-134a. . 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. It is made up of carbon, hydrogen, and fluorine. 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. Since the hose is the stock hose, you cannot tell what refrigerant is inside. The evap is hard to get at. They would then make short "jumper hoses" to connect to the existing stock hoses, refit your old fan if there is a "pusher" fan, and recharge to specs. . As per their results . 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. 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 . All pre-97 XJs use systems with the same basic operating principle, although the parts do change a bit. "Jerky Locker" LMAO I am using that one in the future!Florida = BUGS! BTW, I use a stick thermo in the vents and the laser on the condenser. R-12 is no longer used or produced in many countries and remaining quantities have skyrocketed in price. Replied by Rich928 on topic R12 or R134a. The condensor airflow drops off as the fan clutch dies slowly. How thermostatic expansion valves work | Danfoss A. Pressure/temperature plot of R134a vs. R12 is shown in figure 1. 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. compressor, condenser, evaporator and expansion valve are specifically designed for use with R134a. 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. In a comparison between R12 vs R134a vs R1234yf, R1234yf will pass as the best refrigerant. 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. Even with proper fan operation, missing seals & air dams can effect condensor effeciency. This is a great space to write long text about your company and your services. Is there a source of valves by, say, eaton number? In sum, R12 has done more bad than good. difference between r12 and r134a expansion valve. Yes, the 50F diff (160-110F) on the condenser was at idle, and ambient was about 90F. 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 . It won't be optimal, though. Also called the orifice tube. 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!) 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. Just had knee surgery yesterday, so I"M not exactly hopping around too well. You either get a system that will function well with R1234yf or get any other type. 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. 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. 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. Inhalation of vapor: Inhaling a large amount of R134a vapor can lead to drowsiness, temporary nervous system depression, and lethargy. Gain access to our free AOP (Ask a Professional) Section to get real answers for your questions. Spray it deep, and let it sit for a few minutes. ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. is good, then I should be looking elsewhere? . Its highest value is 1. Stay home and grill your own steaks and stir your own martini. Is it exponential, squared? Above this temperature, the saturation pressure of R134a is higher than that of R12; below, it is lower. Further production of R12 was banned in some developed countries by the Montreal Protocol because of its harsh effect on the ozone layer. Look at where the lines will end up. The pressure at low temperatures is nearly the same between 12 and 134a. In most cases, the systems used have varied components, designs, and service ports. -------------------------1983 Mercedes 240D on R12 and WVO!1192 Mercedes 300D 2.5 R134a1993 Toyota Pickup converted to R134a, Bohica, You say the drop in performance is not linear with too much oil. Flush with a garden hose - do not use a high pressure washer - you can bend the fins flat & damage the condensor.B. 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. Some 1993 and older R12 systems aren't as 'compatible' as you'd think to switch over. R134a compressors are substituted as new to retrofit the R12 system compressor part numbers with different height sealing washers. A final difference is that most (though not all) R-1234yf cars will have a Suction Line Heat Exchanger. The mechanical fan & clutch should be checked as well. evarporator, expansion valve plus flushing out the full system and replacing all the o rings. Only show this user. 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. What effect would it have on performance, if any? Fitting a PF condensor is not rocket science, but it requires some planning. Your decision could be made based on economics, environmental concerns, or both. They can be mounted quite easy,and there is a mounting kit that helps to hang it. We consider the the various types alternative refrigerants that are illegal or not approved to be in two sectors: non-flammables and flammables. Shorting the plug for the refrigerant switch should run the fan when the compressor is on. By: james smith underoath; Comments: 0 . Expansion Valves Catalog E-1, July 2012. However, it was found to be a very bad gas for the environment. 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. Environmental Impact: When R134a escapes into the atmosphere, it contributes to global warming. Also, they are mostly used in refrigeration and automotive air conditioning systems. With new R12 no longer being manufactured, the market price soared to $100/pound. Comparatively, larger R134a molecules should take more space, and a smaller amount might be required. Since 2010, all home AC systems manufactured use a refrigerant like R134a that has zero ozone depletion potential (ODP). Large temperature difference between expansion valve inlet and outlet oReplace expansion valve Air . 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. R134a vs R12 - What is the Differences? - Rx Mechanic Crap! ambulance tailgate conversion R12, on the other hand, is called chlorofluorocarbon (CFC). ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. video clubhouse baseball; nick fairley draft profile; ben davis work pants This is an electronic tool that sucks in air through a tube and across a sensor. You can also check the Aux fan in your case. Though you can purchase 12 or 16 ounce cans of R134a from local retailers it is very difficult to measure out the correct amount into your system. You'll want the expansion valve matched to whatever refrigerant you're using. Why wait for 200f on the engine coolant to start the fan? 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. A lower GWP alternative to R-134a had to be found and thus we have the new 1234yf. The oil used in R12 systems is not compatible with R134a refrigerant. If the system was upgraded by a professional it should have an upgrade sticker. 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. Interestingly, theres one oil type that works perfectly with both types of refrigerants. 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. The cure is to use the newer R134a compressors is sealing washers that are different thickness. You will be fine with a 134a-compatible TXV running R12. Different correction factors are applied to other refrigerants. The #1 question asked by NEW MEMBERS. difference between r12 and r134a expansion valve The difference between R12 and r134a is the BTU carrying capability. Sense ells no existirem. Minor adjustments to the expansion valve and other controls may be necessary for some plans. 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. The chemical composition of R12 and R134a differ. and recharged with mineral oil and 2.2 lbs R12. 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. 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. Like say half a can or so recharge come springtime warm weather or something.
Diamond Question Mark Fortnite,
Who Is The Founder Of The Apostolic Church Nigeria,
Articles D
