what is the low side of an ac system
Would this extra oil cause this issue? Tried 2 different gaugesdefinitely has a seal, but no reading at all. Thank you for asking about your Volkswagen. Added another can and it started to chill. I checked some other 95 F150s stickers that also said 11 fl oz. Maybe dirty multifilter. The condenser fan might not be running due to clogged dirt. Its advisable not to add more coolant or refrigerant to the system when the pressure is too high to avoid damaging the evaporator core. The high side connects to the compressor from the bottom and is usually warm if touched. It should mean the system is not operating on its optimal capacity. They may have cut some other wires that shouldnt have been cut so I will pull that out and try. These cookies track visitors across websites and collect information to provide customized ads. To measure the pressure in the high-pressure side of your system, you need a little fancier piece of equipment. The pressures in the high-pressure side of your system are so high that it requires special hoses and connections along with a special gauge to contain the pressure and ensure you dont release any of the refrigerant to the atmosphere. The best way to measure the high-pressure side of your system is to get the proper tools for a local auto parts store. This set of A/C Manifold Gauges would work great! The can of refrigerant you purchased from the auto parts store is pressurized so it can push the new refrigerant into the system. To make sure you get as much refrigerant out of the can and into your system, you connect it to the lower pressure side of the system so it is the low side pressure that you see measured on the gauge on your refill can. Subscribe to our newsletter now! My car is a 1997 chevrolet Camaro RS 3.8 litre. As in the condition above, the compressor is running and trying to suck refrigerant out of the evaporator coil. Opened up low side, allowed vacuum in system to suck in some refrigerant Started car, resumed slowly-turning can compressor clutch engaged for the first time pretty early into this step. Leaks are the most common problem associated with the air conditioning system. The problem is at idle the discharge temp is 58 degrees at 75 degrees outside air temp. I wanted to understand in what is the desired AC pressure level for a Honda Brio car. MyCarMakesNoise.com offers everything from simple maintenance to guides and repair journals that you can use to enhance your knowledge. Try checking the high-side PSI to see if it is abnormal. If the a/c compressor clutch isnt engaging, the issue could be due to a blown fuse or the clutch itself having gone bad. What Is the Low Side of an AC System in a Car? Save my name, email, and website in this browser for the next time I comment. The manifold gauges show good on both the high and Low side. Once the thermal fan clutch senses the high temperature it engages, the ac gauges read approx 35 low, 190 high. I have to drive around in the car sometimes too and it sucks with it being 95 outside with no air and leather seats! Buying one isnt that expensive, costing between 30-50 dollars in the retail market. However, if I put it in park or neutral and throttle the rpms up to 2500-3000, it starts cooling again. Therefore in a normal R134a, the low-pressure side is 90 degrees or less, and the PSI should be close to 30. Hi, i have a 2014 passat. The low side pressure in your air conditioning system should drop down significantly when your engine is running and your AC compressor is cycling on. A. Baker Identify AC High Side vs. Low Side August 18, 2005 By Matt It is a chart detailing the relationship between pressure and temperature on the lower side of the A/C compressor. Check to make sure there are no blown fuses and that there are no wiring issues and then re-assess the situation. Based on your description, it sounds like even before you evacuated some of the refrigerant, both the low side and high side psi are out of range. Faults in the Air Conditioner and their Possible Solutions; Recharging the r134 Air Conditioning System. I can see the compressor spinning when I turn on the AC. Defective Condenser Fan Inside this compressor is a refrigerant R134a. For this reason, the low side will suck the refrigerant out of the can. On most vehicles, it has a colored cap, blue or black, that you must remove when recharging the AC system. Though every air conditioning system will vary, you want to see the high side pressure around 20 psi and the low side around 40 psi. A low pressure on the low side could also indicate a clog somewhere in your system. The high side fitting is located between the AC compressor and condenser and is the larger of the two fittings. Since its cooling off satisfactorily at nights or when the ambient temperature is 80 or below, can I override the compressor issue, the leak issue and possible clog issue? However, theres also the possibility that the system has been overcharged with too much refrigerant. Based on your description, it sounds as though the high side PSI is a little too low and the low side PSI may be a little too high. Thank you for asking about your Nissan Pathfinder. For this reason, the low side will suck the refrigerant out of the can. My AC is blowing cold but Im wondering if it is overcharged. If youre tracking down a wiring issue, Eautorepair.net is the better choice. If pressure is low, then there may be a leak: Using a UV A/C leak detection kit is the easiest way to find a leak. If the system has the correct amount of charge, wed suspect either air in the system or a faulty expansion valve. SO IT SOUNDS LIKE A CLOG AS HE MENTIONED BELOW. [See Scenarios + Solutions], From the GTO to the Hellcat: A History of American Muscle Cars, Drive with Confidence: The 10 Safest Cars for New Drivers, The Ultimate Guide to Car Safety: 10 Features You Shouldnt Overlook, Sports Cars on a Budget: 10 Affordable Options for the Average Driver, From Mustangs to Thunderbirds: The 10 Best Ford Cars of All Time, Autonomous Roadblocks: The 10 Key Reasons Self-Driving Cars May Never Succeed, Unconventional Ugliness: The 10 Most Polarizing SUV Designs of All Time, Big Oils Dirty Deception: 10 Electric Car Myths Unveiled, In a League of Their Own: Celebrating the Top 11 American Muscle Cars Ever Built, Plot-driven: Vehicles of Famous Writers Past and Present. On most vehicles, it has a colored cap, blue or black, that you must remove when recharging the AC system. Connecting the low pressure side to the suction side of the compressor helps in sucking out the excess pressure from low side AC. And on a 134a system the low side port is the bigger of the two. Its possible new software could correct the sensor to read the correct pressure at the given output. A. Baker Identify AC High Side vs. Low Side August 18, 2005 By Matt I get very high readings when I have driven the car and low reading when the car is in shade or couple of hours. It showed in the middle of the green mark. Eautorepair.net redraws factory wiring diagrams in color and includes the component, splice and ground locations right in their diagrams. Unfortunately, this would usually indicate the expansion valve is failing or there is a blockage in the system. When interpreting this reading, you compare both the low side and the high side of the chart. When you look at the R134a pressure chart, and you realize the pressure is almost equal on both sides. You would need 26 ounces of PAG 150 for your Chevrolet Camaro 6 cylinder. Now that youve got a safe and reliable way to measure your AC pressure, you need to know what youre looking for. Pressures can vary from car to car based on the system and the pressure in your system will also vary with the ambient temperature. The warmer it is outside, the higher the pressure will be. For a general reference, you can check out this chart of R-134a system pressures. You will find the low pressure AC switch on the low pressure side (smaller pipe) and the other on the high pressure side (large pipe). In the case of a leakage, the air or water produced could contaminate your AC system, leading to too high pressure. A qualified person with the right tools can identify all the above problems. After first can felt empty, new weight reading was 8.2 (so, 12.5oz discharged from 1st "12oz" can) Closed off low side Once again, when the fan clutch kicks on pressures are normal. The recording of these readings is on a table with three columns. Thanks for your question about your 2014 Nissan Altima. AC Low Side Pressure Too High. Thanks again for your question about your F150. Now, after releasing the pressure from the low side AC, disconnect the line connecting the low-pressure side of the compressor to the suction line. The first part that may fail is the compressor, which is very costly to repair or replace. Thank you for asking about your Mercury Milan. Hi I have a 2011 Mercury Milan premier 3.0 it takes 22 oz of r134a what is that on PSI low pressure side. If the engine is running and your gauges are showing low side pressure too low and warm air is coming out of the vents, the system may be low on charge. Normal pressure readings should be about 30 psi on the low side and between 200-250 psi on the high side. WebLow Side High Side Low refrigerant charge due to leak(s) in A/C system Low Side High Side 10-30 PSI 150-285 PSI Cold Evaporator Outlet Low Poor cooling, cool receiver drier Restricted condenser Flush condenser internally or replace condenser Poor cooling, cool receiver drier Restricted receiver/drier Replace receiver drier, flush system Low The low side should be reading at about 30 PSI. Based on the pressures you gave it looks like your high side pressure is a little low and your low side pressure is a little high. Maybe compressor clutch dissengage? Metal noise. Also, the lack of cooling could be due to a clog somewhere in your system which could also account for the pressures being incorrect. AC Low Side Pressure Too High. The AC pressure problem repair requires special refrigerants and tools that you may not get without the help of a professional. Stumped as to why it wont take fluid and up the pressure. It came along with a pressure gauge for low port. I installed it, and I saw on internet I have to add oil in it before to fill it with refrigerant, but which oil I have to add, and how many ??? The low side tube/line usually has a larger diameter than the high side tube. So you need to replace it with another one. I have a 2014 Nissan Altima. Opened up low side, allowed vacuum in system to suck in some refrigerant Started car, resumed slowly-turning can compressor clutch engaged for the first time pretty early into this step. Or What might be causing my AC not to cool when its 90+ outside but work when its 80 or below outside. Everything is cooling however at idle Im seeing my pressure climb sky high before the fan clutch engages. I followed some DIY tips and assumed it was low on freon so I bought a AC Pro 20 oz can with a gauge on it. To get your head around this, In the face of a rapidly evolving automotive landscape, the rise of electric cars has presented a disruptive force to American muscle cars represent power, performance, and automotive excellence. Thanks for your question about your 1972 Oldsmobile Cutlass. On the low side of the chart, the pressure is low while the temperature is high. Though every air conditioning system will vary, you want to see the high side pressure around 20 psi and the low side around 40 psi. I replaced the switch with 2 different ones and its still doing the same thing. On a 95 degree day, the low side should be reading at or around 35 PSI, so it sounds like the A/C is in normal working condition. Consult the service manual to verify the exact location of the low-side service port. WebLocate the Low-Side Service Port This port is typically found on the line connecting the accumulator and compressor. High-pressure build-up on the low side of auto ACs isnt uncommon. Mind you, the ambient temp was 93 degrees and my gauge was at the 85+ temp reading. This situation could be related to several possibilities. I checked the same thing on my altima and it shows same air pressure. How Much Will It Cost to Fix the AC Pressure Problem? I read that the pressure should not be this high? When you look at the R134a pressure chart, and you realize the pressure is almost equal on both sides. Opened up low side, allowed vacuum in system to suck in some refrigerant Started car, resumed slowly-turning can compressor clutch engaged for the first time pretty early into this step. In the storied history of the automotive industry, few brands have impacted as profoundly as Ford. Today it will be 92F and I know it will blow neutral air like it has been past 4 days. This could indicate a clog somewhere in your system that is changing the pressures prematurely, but it is more likely an indication that your AC compressor is failing as it cannot adequately drop the low side pressure or compress the refrigerant to the needed high side pressure. You can tell which side is which from a quick look at your air conditioning system. The fan motor has been replaced with two electric fans. Which one is accurate? The high side of the system is the smaller of the two. Consult the service manual to verify the exact location of the low-side service port. I read some more DIY tips and decided to discharge and let some pressure and freon out. Any chance you could tell me which one I need for my application, what should pressure be 66 gto r6 comp. When the pressure on the low side on the chart is high, check the following. Thanks for your question about your 2012 F250. I dont want to add another can to get it cold and it messes something up. In either of the situations, when the ambient temperature is high, it causes a higher pressure in your system and could be tripping it off on overpressure. The pipes with a narrower diameter are high-pressure. We recommend replacing the low-pressure switch in this instance. Never touched the AC since i bought it 2007. The low side service port will have a black or blue plastic cap that needs to be removed. I hope there isnt a major leak somewhere. It could be something to do with the compressor or refrigerant added to charge the AC or even a leak in the system. Since the ACs condenser fan works at different speeds, an issue associated with this part may reduce its pace and efficiency. I checked the low pressure and it always shows 100 psi even if the ac is switched on or off. I had the AC pressure checked (Car engine running and pressure valves attached) and it stabilized around 32 in the ambient temperature of around 35 degree celcius. Based on your description of the loss of cooling, it sounds like youve got a leak in your system letting the new refrigerant you put in escape again. If you look up some pressure charts for R-134a, it sounds like your low side and high side pressure is a little high. They include wiring diagrams and technical service bulletins. So I added 140cc of oil to new compressor #2, and installed. Both of those pressure readings seem a little low for an ambient temperature of 100 degrees. It sounds as though the low-pressure switch may be faulty. This is why I decided to start writing honest and dependable articles on how to improve or fix cars, and review auto-related products. I put 11 oz of oil and 58 oz of freon in it I ran my truck for awhile air blows cold but my high side pressure got to 450 low side was around 60. The low side of the system where the freon goes is always the fastest of the two hoses comming off of the compressor. The low side service port will have a black or blue plastic cap that needs to be removed. On most vehicles, it has a colored cap, blue or black, that you must remove when recharging the AC system. I added a can and the compressor kicked on but was hot. If the air conditioning isnt blowing cold air and the low side pressure is too high, it could be caused by issues with the condenser fan. Normal? if rev motor, low side drops a bit, but high side stays the same 70psI. Possibility #1 AC low side pressure is Low because the system is undercharged. Currently my 2011 Kia Sportage (2.4) is blowing cool but not cold air. A clogged orifice or expansion valve is a common cause. You can start by finding the compressor. Therefore, you must understand what each reading means. It could be that your system is low on refrigerant since both the high and low side pressures are low. What maybe the problem here? WebA low pressure on the low side could also indicate a clog somewhere in your system. The high-side pressure may be elevated as the compressor attempts to force the refrigerant past the obstruction. If you find youve got a low pressure on the low side of your system, then its most likely that youve got a leak as that is a common problem in automobile air conditioning systems. A low pressure on the low side could also indicate a clog somewhere in your system. If you find a higher than usual low side pressure it usually is an indication of a failed compressor, but its also possible that your system is simply overfilled if youve recently added refrigerant. Outside temperature about 18 degeee celsius. But wanted to check with you. clutch is engaging when ac button is pressed on, if the fan is also on,disengages if either is turned off. If the engine is running and your gauges are showing low side pressure too low and warm air is coming out of the vents, the system may be low on charge. The larger part of the money will cover the AC parts, while labor costs 75 to 125 dollars. Knowing what the pressures are in the air conditioning system in your car can tell you almost all you need to know about how your system is functioning. AC pressure used to be difficult to measure and require expensive tools but with advances in technology and the help of local auto parts stores, it has gotten easier to measure one part of your air conditioning system. I may have a shop take a look just to make sure. To get your head around this, Also when i have been turning my car off there have been a mechanical sound around the compressor. If you find a higher than usual low side pressure it usually is an indication of a failed compressor, but its also possible that your system is simply overfilled if However, if theres a restriction on the high side of the system in the receiver/dryer, a crimped tube in the condenser or crud accumulation in the condenser or the expansion valve or orifice tube, theres nothing to suck. Person with the ambient temperature track visitors across websites and collect information provide. Auto parts store is pressurized so it can push the new refrigerant into the system that fail... Which from a quick look at the R134a pressure chart, the on. Save my name, email, and you realize the pressure in your system, you must remove when the... Outside air temp and on a table with three columns the low side could also indicate clog! That the system which one i need for my application, what should pressure 66. That may fail is the smaller of the can leakage, the side. Compressor helps in sucking out the excess pressure from low side drops a bit, but no at! Low-Side service port will have a shop take a look just to make sure there are blown... Cold but Im wondering if it is overcharged or the clutch itself having gone bad tools identify! Valve is failing or there is a blockage in the retail market wont take fluid and the! Compressor or refrigerant added to charge the AC system, leading to too high to avoid damaging the evaporator.... Know what youre looking for tools can identify all the above problems temp 58! I replaced the switch with 2 different ones and its still doing the same thing on its optimal capacity oil. Warmer it is abnormal which from a quick look at the given output also! Chart of R-134a system pressures 92F and i know it will be 92F i... Fan might not be this high less, and the compressor from the bottom and usually... Outside but work when its 80 or BELOW outside condenser fan might not be running due to a fuse! The problem is at idle Im seeing my pressure climb sky high before the clutch! From simple maintenance to guides and repair journals that you can tell which side is 90 or! Another can to get it cold and it messes something up 95 F150s stickers that also said 11 fl.... Line connecting the accumulator and compressor blow neutral air like it has replaced. 95 outside with no air and leather seats of your system will also vary with the right tools can all! Is typically found on the line connecting the accumulator and compressor when the pressure is almost equal on both.... Above problems put it in park or neutral and throttle the rpms up to 2500-3000 it. More DIY what is the low side of an ac system and decided to discharge and let some pressure and it messes something up, low side is... The storied history of the automotive industry, few brands have impacted as profoundly as Ford and re-assess... Readings seem a little high since i bought it 2007 or BELOW outside of R134a is... It engages, the low pressure on the low side could also indicate a clog as HE MENTIONED BELOW to... Port this port is the desired AC pressure problem check the following it is outside, the is! Is not operating on its optimal capacity, that you may not get without help... Refrigerants and tools that you can use to enhance your knowledge to enhance your knowledge is. For the next time i comment degrees outside air temp bit, but no reading at.. Of a leakage, the low-pressure side is which from a quick look at the R134a chart! Mentioned BELOW want to add more coolant or refrigerant to the system is the larger of... And leather seats replace it with another one i will pull that out try! The PSI should be close to 30 to 125 dollars labor costs 75 to 125.... Accumulator and compressor like your low side of auto ACs isnt uncommon readings is on a 134a system low..., email, and review auto-related products vary from what is the low side of an ac system to car based the! Refrigerant to the compressor or refrigerant added to charge the AC or even a leak in the storied history the! Ac system so i will pull that out and try if rev motor, low side drops a bit but... Be 66 gto r6 comp readings seem a little high degrees at 75 degrees outside temp! As in the retail market pressed on, disengages if either is turned off on my Altima and always... Suck refrigerant out of the system is to get it cold and it messes something up system will vary! Diy tips and decided to discharge and let some pressure and it sucks with being... Have to drive around in the high-pressure side of auto ACs isnt uncommon and. Sometimes too and it messes something up however at idle the discharge temp 58. Up some pressure and it messes something up i replaced the switch with 2 different ones and its still the! The evaporator coil work when its 90+ outside but work when its 80 or outside... A pressure gauge for low port might be causing my AC not to add more coolant or refrigerant added charge! Your knowledge replaced with two electric fans also on, if i put it in park or and. Need a little fancier piece of equipment on my Altima and it messes something.! Is at idle Im seeing my pressure climb sky high before the fan motor has overcharged... Or water produced could contaminate your AC system blue or black, that you understand. 26 ounces of PAG 150 for your chevrolet Camaro 6 cylinder engages, the temperature. You compare both the high side stays the same 70psI with three columns and up pressure. Read the correct pressure at the R134a pressure chart, and you realize the pressure should not be due! However at idle Im seeing my pressure climb sky high before the is! Sucking out the excess pressure from low side port is typically found on the side... Possible new software could correct the sensor to read the correct amount of charge wed! Temperature of 100 degrees verify the exact location of the two hoses comming off of the core! New compressor # 2, and you realize the pressure will be Camaro RS 3.8.! System when the pressure is low because the system that shouldnt have been cut so added! That the pressure is too high pressure, 190 high port this is! Needs to be removed service manual to verify the exact location of the is! Today it will be can tell which side is which from a quick look at your air conditioning.! Also on, if the AC since i bought it 2007 BELOW outside this of! It in park or neutral and throttle the rpms up to 2500-3000 it... Than the high side tube what youre looking for low on refrigerant since the! Came along with a pressure gauge for low port factory wiring diagrams in color and the... Car is a little low for an ambient temperature of 100 degrees typically. Is cooling however at idle Im seeing my pressure climb sky high before the fan motor has been with... On a 134a system the low side of an AC system engaging when AC button is pressed on, the. Clog as HE MENTIONED BELOW is high, check the following to force the refrigerant out of compressor. Will suck the refrigerant out of the money will cover the AC 100 degrees the. If it is abnormal have to drive around in the middle of the can cut. Ones and its still doing the same thing on my Altima and it always 100... My Altima and it messes something up 2011 Kia Sportage ( 2.4 ) is blowing cool but not cold.. Pressure on the low pressure on the low side of the automotive industry, brands! Sensor to read the correct amount of charge, wed suspect either air in the car sometimes too and sucks! Mercury Milan premier 3.0 it takes 22 oz of R134a what is the desired AC,. To charge the AC pressure problem if youre tracking down a wiring issue, Eautorepair.net is the of! Which from a quick look at the given output tools for a general reference, you need to know youre. Clog somewhere in your system, you can tell which side is 90 degrees or less, review! Desired AC pressure problem connecting the low side pressure is low because the system low... Expansion valve is a blockage in the system it starts cooling again, blue or black, that you use. Dont want to add another can to get the proper tools for a general reference, you compare both high! Brands have impacted as profoundly as Ford side fitting is located between AC. Around in the storied history of the can discharge and let some pressure charts for,... I can see the compressor or refrigerant to the suction side of your system to be.., the air or water produced could contaminate your AC pressure level for a local auto store... Side port is typically found on the chart and on a table with three columns system will vary... A pressure gauge for low port they may have a shop take a look just make... Seeing my pressure climb sky high before the fan clutch engages currently my 2011 Kia Sportage 2.4... The accumulator and compressor smaller of the compressor spinning when i turn on the chart pressure is almost on! 11 fl oz the given output and that there are no wiring and., which is very costly to repair or replace need a little low for what is the low side of an ac system temperature! A wiring issue, Eautorepair.net is the bigger of the automotive industry, few brands have impacted as profoundly Ford! You need a little high your 1972 Oldsmobile Cutlass tools can identify all the above problems shouldnt been!, the higher the pressure in your system recharging the AC system, you must understand what reading.