With R134a you do not rely on the site glass. Existing technology: R134a has been in use in the refrigeration industry for very many years, and theres so much information about the safe use of the product. An extra half ounce? . Discussion in 'Technical' started by Jsarnold, May 25, 2012. You do not need to replace the expansion valve in most cases. 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. Thanks again. You'll want the expansion valve matched to whatever refrigerant you're using. 37 in 2005 tacoma, R134A. don't know enough about the subject to explain the choices.However, a few days ago I called the dealer to see about an OEM TEV and they said something that made me feel a little bit better; the same part number superceded every application back to the '60s, and that they couldn't do that without engineering signing off on it.Still, I would feel a lot better if I could see something written officially that compared the flow characteristics and performance of r12 and 134a TEVs are concluded that they were interchangeable in automotive applications.If someone knows of such a document I would sleep much better!Walt Edited: Mon September 12, 2005 at 8:13 PM by wamcneil. Crap! This may be the source of your oil confusion. The compressors used by refrigeration plants to compress gas require oil to help lubricate its moving parts.
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. CONCLUSIONS The differences in the theoretical C.O.P.H calculated for R12 and R134a are consistent with values quoted in the literature. 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.
R12 or R134a - 928 Owners Club Forum Once you have replaced the OEM condensor with a PF unit, you will need to make custom hoses to mate with your OEM system. Are r12 and r134 fittings different? 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? Since then, the industry standard has been R134a, which is an efficient replacement. However, R12 refrigerants are still used as fire retardants in aircraft and submarines. You will be fine with a 134a-compatible TXV running R12. I could easily be over at least 2 - 3 ounces over on the oil. asia pacific stevie awards 2021. gin, amaretto cocktail. 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. 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. A Lot of the fins are bent, especially at the top. maintain the A/C of older cars. The best replacement for R134a is R1234yf, while R12 refrigerant replacement was R134a. Edited: Tue July 17, 2007 at 3:25 AM by bohica2xo, I believe there is only one switch - the refrigerant switch. 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.
difference between r12 and r134a expansion valve ESP when a compressor has frozen. 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. Its duty is to convert toxic gasses produced by the engine into A brake cleaner is a powerful solvent for cleaning dirt from the brakes and other car components. CLUTCH CYCLING SWITCH. ). 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. The original CFC expansion valve used for R12 needs to be replaced with an HFC one for 134a to feed the evaporator correctly. R12 contains a chemical called chlorine that destroys the ozone layer, thereby causing potential environmental risk. Even with proper fan operation, missing seals & air dams can effect condensor effeciency. If you you dont have the free time to play then you are better off to pay a technician.
difference between r12 and r134a expansion valve 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. Welcome to rxmechanic.com. shown for the parallel flow, aluminum condenser that is listed. Are you sure you have an R4? The R134a compressor has a 1/8" step in on the high side port. If the system was upgraded by a professional it should have an upgrade sticker. 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. Thread starter goldNSX; Start date 1 August 2009; Tagged . 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. At 2000rpm, windows open, highest fan, hi pressure stabilized at 225 psi, low 25psi.Ambient 81F, vent 61F. 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.
PDF Experimental analysis of Thermostatic expansion valve, Constant and he synthesized R-134a in 1936, 5 years after R-12 was . This kit comes complete with Expansion valve, o-ring kit, and 1ft. |. Make sure to wear safety gloves, goggles, and shoes when theres a possibility of exposure to the chemical (R134a). Thanks so much Bohica - you've save me many more hours of fruitless speculation. Is there a difference between a R134a expansion valve and an R12 TXV? I put one in my old daily driver '79 Chevy tank (r-12), and it really made a difference. The global warming potential of R134a is 1430. 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. To ensure the right charge, you must fill the new system with between 75 and 85% of the factory-set capacity for optimal cooling. It is a haloalkane and hydrofluorocarbon (HFC) refrigerant that has thermodynamic properties, potential global warming for one hundred years, and insignificant ozone depletion. video clubhouse baseball; nick fairley draft profile; ben davis work pants It's helluva humid and hot here in north florida, and I drive around all day for my job. 3 ounces? is good, then I should be looking elsewhere? 4) Repeat step 2, making sure it will fit. 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. July 3, 2022July 3, 2022. 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. The good thing is that after you convert to R134 you can top off the system easily and cheaply. gital control scheme. Using R134a requires that Polyolester (POE) lubricant must be used in the compressor. Compared with the cost-performance ratio, R507 is 30-40% . You'll get marginally better performance out of the change as the expansion valve is matches the refrigerant characteristics. 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. Replied by Rich928 on topic R12 or R134a. Bad Car A/C Expansion Valve Symptoms. compressor, condenser, evaporator and expansion valve are specifically designed for use with R134a. Attach the R134a charge port adaptors, there are two types.. one of which you need to remove the old R12 valve cores. Flush with a garden hose - do not use a high pressure washer - you can bend the fins flat & damage the condensor.B. 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. A discussion of the relationship between valve capacities and superheat set-tings can be found in Bulletin 10-9. -The amount of R-134a needed will typically be 80-90% of the R-12 charge.
A Comparison Study of the Thermal Performance of R12 and R134a 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. 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. R404a is a zeotropic blend with a temp glide , because of the mixture of 2 or more refrigerants. Replace the drier with a drier that has a desiccant that is R134a compatible, use new R134a o-rings. Replacement expansion valve for R134a or R12 A/C refrigerants, with O-ring connections.
R134a compressors are substituted as new to retrofit the R12 system compressor part numbers with different height sealing washers. 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. It is made up of carbon, hydrogen, and fluorine. -------------------------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. 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. Hot coolant migrates up through the core by convection (is that the word? 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. 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!) It is made up of carbon, hydrogen, and fluorine. R134a refrigerant fittings are different size. Catalog E-1, Thermostatic & Automatic Expansion Valves / Page 1 Table of Contents . (On firewall where A/C lines go into cab.) Spray it deep, and let it sit for a few minutes.
Amazon.com: 134a Valve ~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446. 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.
R12 to 134A conversion. | Allpar Forums Safe but sorry! So, instead of using R12, other better options include R401b, R134a, R401a, etc. This is because R134a. I have the original (R12) style expansion valve in the Maverick AC system. #4. To bless the system the technician should attach a R134a sticker somewhere in the engine compartment to note the car is using R134a. How is 1234yf different from . The original rubber a/c hose lines in your car will leak out R12 through the hoses lining. The system will be checked for gross leaks while under vacuum. These two refrigerants are the older types and are not used in newer refrigeration and air conditioning systems. The higher the ambient temperature the higher the high side pressure. It's best to determine on a case-by-case basis while monitoring system pressures and output air temperature. As R134A refrigerant has different operating characteristics and pressures this valve is not necesssry. So I probably put the highest suggested amount in to be safe. The next piece of equipment to track down leaks is a leak sniffer. The ozone depletion potential of a chemical is a factor that shows the level of degradation itll cause to the ozone layer that surrounds and secures the earth from harmful radiation. Hmmmm. As R134A refrigerant has different operating characteristics and pressures this valve is not necesssry. The old compressor used R12 and the new unit will be R134a. You do not want to exceed the systems high side recommendations. 5. 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. An orifice tube is just a fixed nozzle that pisses refrigerant into the evaporator without any sort of feedback. 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. in /nfs/c05/h04/mnt/113983/domains/toragrafix.com/html/wp-content . 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 . When I compare parts, 93 uses one part number and 94 has a different part number. 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. Performance doesn't seem to have improved. In addition, R134a refrigerants are not only used in auto air conditioners, they can be used in freezers, aerosol cans, and refrigerators. R134a has a smaller molecule than R12 so R134a will leak out sooner than R12. It is also used in automotive car conditioning and the plastic industry. There are significant differences between R12, R134a, and R513A, which must be considered when handling, processing, applying, or retrofitting with these refrigerants. R12 and R22 are both now banned by the EPA in the United States. It runs between the condenser outlet, receiver/drier unit and expansion valve at the firewall. 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. I'll report back on the aux fan on performance next. It is possible I have 10 ounces (250 ml) in the system. The crossover point is approximately at 64F. I don't know where it is getting the switch off command, or why the vent temp drops steadily. leading to corrosion of expansion valves, capillary tube plugging, and compressor bearing . A. Pressure/temperature plot of R134a vs. R12 is shown in figure 1. . Besides R134a there are some other refrigerants that are approved to replace R12 and there is a long list of refrigerants that are not approved. Hopefully after you have read this entire page you will have enough information to determine which type of refrigerant is best for you. Add to cart. 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. This is due to many facts: R134a refrigerant is about 10% less efficient in moving heat than R12! The catalytic converter is an essential component of your car's emission system that helps save the environment from harmful emissions. From memory, I put in at least 8 ounces of oil, probably around 10 ounces in there. 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. 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. The #1 question asked by NEW MEMBERS. 4 Stars & Up & Up; 3 Stars & Up & Up; 2 Stars & Up . 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.
Any ideas from the info above? As per their results . hardly noticable. Edited: Sat July 14, 2007 at 10:22 PM by fonebone. Operating Pressure/Temperature Differences The pressure/temperature curves for R-1234yf and R-134a are very similar. Consider using the newer valve, even with 134a stamped on the valve. 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. Different correction factors are applied to other refrigerants. Carefully study the chart and compare the following: To a large extent, the choice is up to you.
difference between r12 and r134a expansion valve But with an R4, better too much than too little.3) A TXV optimized for 134a will be ok with R12.4) The airflow across the condensor is crucial to good performance. 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. A/C receiver difference between R12 and R134a? 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. R134a vs R12 refrigerant? R134a has the chemical formula CF3CH2F and is known as tetrafluoroethane. You will be fine with a 134a-compatible TXV running R12. R12 is CFC: Even though R12 is one of the most commonly used refrigerants, it is CFC. 10,000BTU conduction heating? Took me a while to figure that one out, and how to say that. The money you will save by will pay for the R12. and an evaporator core and expansion valve that are optimized for R134a . #19. Therefore, its most suitable for both commercial and domestic environments. 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. 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 . difference between r12 and r134a expansion valve. Very interesting! Biggest you can fit in there is best.
Effects of alternative refrigerants on the ejector dimensions for The value of carbon dioxide is 1. a 50f delta across the condensor is good, but I suspect that is an idle reading. Rules governing changing from the former to the latter differ between countries. 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 . Safety: R134a is safe to use as its non-flammable and cant explode. Kommentare . Is that why expansion valves are specific to R12 or R134A? We sometimes use a relay switched from the compressor clutch to run fans. Answer: OK, I'll bite. And no, you cannot "drain' excess oil out. The general practice of charging the system with 15% less refrigerant adds to the thermal deficiency of R134a. Swapping the components isnt a herculean task, but recharging the AC is a challenge. Please enter a password for your user account. 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. I'm doing one thing at a time so I know what the cause was.
PDF R134a R513A - Tecumseh Products The OEM spec is 2300 rpm @ 12.6v (engine stopped fully charged battery). had writing on the side that said R134a. There are other refrigerants: some of which may work, some of which dont work, some of which will destroy your a/c system and some of which are dangerous. This allows the refrigerant in the condenser to be void of oil particles. I had to vaccum the system for 2 hours and recharge 4 oz of PAG oil plus 36 oz of 134A freon (3 cans). Right now you know you have a bit too much, but with a CR4P compressor this is an insurance policy. Then, subtract that result by 0.25 pounds to get the proper amount of R134a charge. R12 systems used mineral oil, but unfortunately mineral oil doesn't dissolve in R134a.
Unfortunately, the R12 refrigerant doesnt always blow cold air. 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. There is only a temperature switch on these cars as far as I recall, and it just switches on the aux fan. The difference between R12 and R134a TEV (exp valves) is primarily the 'superheat'. The best oil that runs well with R134a is PAG oil or Polyalkylene Glycol. 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. It's not just the poor performance - the cooling just stops working after a while. You may need to adjust the valve in a bit to get desired superheat. Before we mentioned that you can add approximately 5-6 ounces of ester oil to the compressor. Instead, top off R12 with R134a refrigerant. Why wait for 200f on the engine coolant to start the fan? GWP is a measurement of Greenhouse Gases and their effect on Global Warming. Ask Our Pros-Owner Assistance - NO DIY advice will be given. Anyone know what happens when an R12 expansion valve is used in a system charged with R134A? difference between r12 and r134a expansion valve why is miles raney not on homestead rescue June 21, 2022. manila mayor candidates 2022 The current expansion valve is FF - 1/4 - C. Is it neccesary to replace this valve? What is the refrigerant property involved that has caused this? Rich Membership Chairman Using R134a in an R12 system will cause the oil not to move with the refrigerant, causing a system failure and probably won't even cool the system well, if at all. A slow loss of cooling at city speeds is usually related to condensor capacity & airflow issues. What was the ambient when you took that reading?Jumpering the aux fan is a common thing here in the desert. El juny de 2017, el mateix grup va decidir crear un web deDoctor Who amb el mateix objectiu. Before R12 was replaced with R134a in 1995, it was mostly used in trucks and cars. But as there's not a big difference, people say you can suffice with either. Yes, the 50F diff (160-110F) on the condenser was at idle, and ambient was about 90F. 3) A/C Compressor Always On. What is usually sniffed are all the connections in the system: hoses and compressor, condenser, drier, expansion valve and evaporator fittings. Bohica, I appreciate your help with this. I remember I had the wrong seals and it leaked some oil, so I put some more in.Bohica - I tested the pressures. Participate in over 40 different forums and search/browse from nearly 3 million posts. 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. In most cases, the systems used have varied components, designs, and service ports. 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. Its chemical symbol is CCl2F2. Warning: "continue" targeting switch is equivalent to "break".Did you mean to use "continue 2"? R12 and R22 are both now banned by the EPA in the United States. The butylcellusolve or the citrus solvent will dissolve the carcass in a few minutes. Any suggestions, or do you need to know the hi/lo readings? Talk about what services you provide. R134a is called tetrafluoroethane (HFC). The larger line at the expansion valve is the suction line. If you have the work done, be sure you find a true "A/C" shop that can make up lines. As noted, measure up front as best as you can to get as close to the aftermarket dim. Look at where the lines will end up. 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. B. The experimental values of C.O.P.H obtained with the R134a/ester charge were 20.2% The problem with not being an expert is that you don't know what is important and what's not. I mean, really a lot. 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. Expansion valves are an active device, they regulate the flow of refrigerant to the evaporator depending on evaporator temperature. Paul:It is never a waste of my time to chat with someone that understands the problem, and wants to fix it. That way I will have reduced the oil by about 1/3 (assuming the oil is mixed evenly through the system). 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. I just got some hi/lo side gauges so I'm going to take readings, if they are needed. 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. Most of all the differences gravitate to longevity, functionality, and safety. 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. Is that reasonable?Vent airflow is good, I think. Unfortunately, the oil only mixes with the refrigerant as a liquid. But as there's not a big difference, people say you can suffice with either. Be sure to test @ 1500 to 2000 engine rpm, and record the ambient temp as well. This works when the R12 charge specification is listed in pounds.
Can I Use Automotive r134a in a Refrigerator | An Expert Guide Condensers designed to release greater amounts of heat help to expel the greater amount of heat which R134a removes from the cars interior. 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. _____ 2012 E350 2006 Callaway SC560 . 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. Thus, when the system is running, condensing the CO2 is not a problem.
System has been working fine for a year. Big . By noting the ambient temperature you can look up what the preferred high side pressure should be. Skin contact: If the R134a (liquid) comes in contact with your skin, it could cause a burn. Flushed, vacuumed etc.