So some five years later after this tip was recorded and in a sunny and hot London I attempted to recharge the A/C on our BMW Mini. Using static readings I couldn't get the A/C working and was about to give up. Watched this tip and tried again, was simple to do (clearly the static readings were way off) and all working fine - thank you !!!
If your gauge set does not come with the temperature pressure scale you can go online and get a r-134a temperature pressure chart and use that for your diagnosis work.
Just what I was originally looking for to understand what was happening. Understanding that there are different pressures depending on whether or not the A/C is running seems crucial for any newbie DIY A/C charging. Wish it was included more on A/C charging vids. Thanks for this great video.
I really appreciate your videos. For several years you have helped keep my old 2010 Focus going like a champ. I do some "easy" work myself, but even for things I don't do myself, it's helped me understand enough that I can communicate effectively with my current mechanic about what my problem is and my theory of what might be broke.
Love your videos BUT it’s definitely not totally worthless because the static check will tell you if you have refrigerant in the system which is a great way to start your T/S. Won’t tell you if it’s a full charge but will tell you if you’re empty.
I watch very many video's on RUclips on many different disciplines. Your video are some of the very best I have seen and extremely educational. You are doing a great service to everyone who watches your videos. Thank so very much.
After you refilled it with 3 oz why would somebody look at the gauges and say they are fine. They showed 60 and 60 static. That is low. Don't need a trained eye for that. Who would say that is good? What it did show was that 3 oz will give you 60 and 60. This does not explain why you should not use static pressure for the initial part of diagnostics. Or am I missing something?
Put me in that category of missing it. The only thing I get from the video is you need the static pressure chart, which is obvious to most people. It isn’t explained why there’s more to it than that.
I had a 02 expedition come in the other day and it was missing the orifice tube. It almost kicked my butt until one of the senior master techs came and helped me. What got me was that the pressures were pretty good but the low side was a little high around 70. The master tech diagnosed it by putting his hand on the pipe where the orifice goes and said there is no temp difference on either side of the pipe where the orifice tube should be. I put in a new orifice tube and the system worked perfectly. I would like to see a video on how to properly diagnose that problem. Thanks
The low side at 70 was a dead giveaway that is nowhere near ok. Odd concern for sure though but a temp gun is what I would use to check either side of the orifice. In a txv system with a scroll compressor this can be misdiagnosed a weak compressor or failed txv. The expedition uses a standard FS-10 Swashplate compressor and Fixed orifice which is key here it makes it much easier to diagnose.
love those compressor control valves that fail and they say you must replace the compressor. Nope just changed the valve on a 2015 festiva for a intermittent no cooling. Works great.
Checked the static pressure on the jeep. High side read what I expected 117 psi but the low side read 300 psi. Everything is new. I’m thinking the compressor. What do you think. FYI ac does work when until it gets pass 107° at that temp I would expect air in the high 60’s. It’s actually in the low 80’s.
You just proved that using the static pressure reading is the easiest and most reliable way of checking the charge of an A/C system. Why are you saying the opposite?
Bottom line is you can't change physics. Same thing that HVAC and low, medium, and high temp refrigeration techs miss all the time. Moisture in the system always throws techs too... Cannot compress water.
Do you have a chart that you recommend a guy use for correlation of pressure to temps? I’ve been watching your videos on the diagnostics and I’ve learned a ton, I work for a Deere Dealership and work on Ag equipment. I was able to diagnose a plugged evap thanks to one of your videos.
Just to be clear. In this scenario your reading 61 lbs static pressure on an undercharged system with an ambient temperature of 86 degrees. So the static pressure is way too low for 86 degrees. It seems to me that with the right gauges or a chart to make sense of the static pressure readings you could tell it's undercharged by the static pressure reading. Is this correct or am I missing something. I'm just now starting to learn. The method I followed was to use the gauges with the engine and the AC running and compare the readings to a chart for R134A auto systems. I didn't pay attention to the static pressures. Thank you for the video.
I'm glad I'm not the only one who noted this. The "untrained eye" must mean not referencing an r-134a temperature/pressure chart. Static pressure alone is not enough but for gross under/over charge conditions, it's a good start I would think
Your reading was reflecting the freon PSI did not reflect ambient temp. as the freon was colder then ambient from being drawn in the system. If you would have waited until the freon warmed to ambient temp. reading would match. Noting to do with type of AC system.
Issue im having is the pressures are changing as the Trucks RPM change. All new components but its not cooling. Idle at 55/170 reved to 2000k at around 30/220. Wont cool unless reved or driving. Any ideas?
Hello I purchased one of the cheap refrigerant cans and when i first hooked it up to the low side it was not reading on the gauge and the compressor was not on. I began charging it up then the compressor would turn on dropping the reading to nothing then turn off again bringing the reading up to what the gauge say a good charge. but then as soon as the compressor comes back on the gauge pressure would drop. My question is do i charge the system with the compressor on or off?
Yo, if you let the AC run a bit after putting in the 2ozs of Freon, then turn it off and let it stabilize, the static gauges will show very low pressure so, I disagree with this video. Whose gonna squirt 3 ozs of freon in and not run the AC. Who measures a car without first running the AC? I disagree with assessment on static pressure being worthless to the untrained eye.
I replaced my compressor on a 2011 Explorer XLT and the compressor clutch won't engage. I made sure to oil the new compressor and I charged the system with a full can. The A/C lines in this car is kind of long and runs to the back for the 3rd and 2nd row cooling so I am not sure if it just requires more coolant or no. The relay is fine. I ran some FORscan tests and I got a reading of 910 kPA for the acp_press. No codes either. Have I done something wrong?
TimeHopeFaith Before charging w the can, Did you get a vacuum pump and pull a vacuum on your system down to about 29 inches for about 2 hours? Also, did the can have the exact amount of R134 that your car calls for? There should be a sticker somewhere under the hood that tells how much your system is supposed to have.
You mean to say by static reading we get to know nothing abt the refrigerant whether it is low or high. Only by operating readings give accurate results.
I have an issue with my AC I tried charging it and I had to bypass the AC so we can turn on but every time I charged it it blows back the AC outside of the system from the compressor
Those charging cans with gauges--mine has printed instructions to start the engine and run the AC on high setting--fan up before connecting the charging hose to the low port. I have taken flak from an auto forum for using the "Can" without acquiring a manifold gauge set to check the system. Presently, after using the "Can," my AC is cold and the temp gauge I inserted into the mid-dash center vent reads about 40F at the hottest point. Definitely great for the past 2 weeks as the weather here is 90+ and very humid. There is mucho sweat on the low side lines under the hood--so much so, it is dripping water. The vehicle is 17 years old so I am not about to put $200-500 into a repair by a shop.
2000 mustang gt when the ac is on the clutch doesn’t stay engaged for more than 2 to 3 seconds and the idle is going up and down ,what is wrong any help will be appreciated this is Rick from sf calif
Prob bad blend door control. Cause once coolant gets hot inside heater core then hot air blends with cold air. U can try to bypass heater core to determine problem
Question. I have a Dart 2013 my pressures are not equalizing, a guy at the ac shop told me nowadays static pressures not equalizing doesnt mean much. Whats the truth?
i have taken my 2018 F 150 into ford dealership and they could not fix truck. The A/C works great for the most part...but since i owned it (1 Year) the A/C on 5 separate occasions did not work . is there a fix for this
I HAVE A, 2011 FORD ESCAPE ,LOW SIDE IS 125PSI HIGH SIDE 210, THIS IS WHEN RUNNING, I HEARD THE DRYER FROM 08, THROUGH 2011. WILL BURST AND FILL EXPANSION VALVE. WHAT DO YOU THINK.
I have 08 edge and it will not blow cold compressor works its fully charged i changed the expansion valve and the compressor and still no change the line gets frosty when it takes in the refrigerant but after that nothing and it seems like its getting trapped somewhere any tips
i have a motorhome that is short cycling every 2 to 5 seconds with low side at 35 to 45 and the high side is the same with ambient temp at 77. would you start out with replacing compressor. thanks
Those readings seem low. I know your post is 2 years old, and hopefully you got it fixed, but if not, look up an a/c pressure chart for r134a (if that is what the system is running). Next step would be to find why it is losing pressure (a leak somewhere). Your low side pressure is good, but high side is way way too low. If you only had a weak compressor, the low side would also have been high.
I have a 2013 F-250 Super Duty The clutch on the compressor it kicks in for a few minutes then it cuts off in a minute or 2 cut back on The refrigerant is good Any help will be greatly appreciated
Nope I stick to a regular manifold gauge set they have not let me down yet. Kind of like the power probe everyone talks about for electrical diag still to this day I have not found a need for one.
FordTechMakuloco same here, just use a basic test light and the trusty Fluke. I renamed the Power Probe the module zapper, guys try to activate solenoids and kill control modules in short order by backfeed.
Sorry to be so off topic but does any of you know of a method to get back into an Instagram account..? I was dumb forgot the account password. I love any assistance you can give me!
2004 F150 4x4 refrigerate liquid line keep bursting off. It will charge and run for about a day and pisssss the hose will blow off near fire wall. I purchased new line also 2, two orifice tubes. I have totally used 9 cans of Freon...Please help !!! Thanks
Interested in this series because I have an issue with my a/c. When I leave my house, no matter what direction, I am up to 50 mph almost immediately so the air works great. I recently spent a few days in the city where I averaged less than 30 mph and my system struggled. After checking with gauges, not sure I need to add more Freon. Was wondering the cost to purge and refill my system with proper amount? 2006 F150, 5.4
If a refrigerant that changes to liquid at say ( example ) 100 psi then a static system with 2 ounces of liquid refrigerant would have same pressure as same system with 20 ounces of refrigerant at same temperature. Correct?
I'd like to have seen the gauges after fully charging the system with the correct amount of freon. Someone said that the static pressures if they are not equal after the vehicle has sat for a period of time that you automatically know that there is a restriction in the system. Is there any merit to that idea?
with a TXV (or other valve) fail, or other contaminant restriction anywhere in the system, the pressure with not equalize as quickly as normal between low and high sides, static.
I had 30 PSI low and 300 PSI high on my 2010 Focus, which may still be overcharged. I had the system way overcharged when I blindly added some leftover R134a without looking at the high side, not realizing the compressor was then driving the high side pressure to the safety cutoff at 435 PSI. AC was ineffective as a result, with the low side only dropping to 60 PSI, not low enough for the expansion valve metered refrigerant gas to expand sufficiently into the evaporator for cooling.
I just put my gauges on a 2006 H3 Hummer, the low side static pressure pegged the gauge, and the high side static pressure was in line, with engine on low side fluctuates from 20 psig to 70 psig, I’m guessing expansion valve, any help would be appreciated
15 mustang GT. Bought a cheap refill bottle. Clutch isn't engaging, but scared to overfill. Assuming the static pressure is just throwing me off and I can keep adding refrigerant? I added maybe half of a 20oz can. How much do you need to actually trigger the clutch?
Thank you for explaining about the Static Pressure. What would be your opinion about my system. I have static pressure of 135 high and low side with outside temp of 86 with an engine compartment temp of 95 degree and inside car temp of 105 With the car and AC on I have 49 on the low side and 235 high side. I have air vent temp blowing at 68 degrees. My issue is that the compressor seems to cycle a lot when it is hot outside and doesn't constantly stay cold but seems to work great in the mornings or evenings when the outside temp drops down around 75. Electric engine fan is working. Thank you
Good Stuff Man! Correct me if I'm wrong please. The static can be used as a general idea based off how ii correlates with the temp. In this video with just 3oz it showed as if the temp in your shop was around 60 degrees. That is the trained eye you're talking about? Where as the first reading indicated the correct 86 degrees using static.
I never consciously realized it but static is a good indicator of charge, I’m working on something atm where compressor won’t turn on but pressure, and how it correlates to temperature led me to believe refrigerant was low (also prevent compressor engagement)
I keep seeing that the static pressure in psi of R134 in a properly charged system should basically equal the ambient temp in degF. But in this video, static pressure was 100 psi when ambient was 86deg F. What's up?
@@mrau92me That only holds around 68 deg F, give or take 5 degrees. When the temperature goes higher, the pressure goes up at a faster rate than the temperature. Similarly, as the temperature goes lower than 68 deg F, the pressure drops more rapidly. Something like this: Pressure Degrees Fahrenheit 53.88 57.2 58.43 60.8 63.2 64.4 68.21 68 73.46 71.6 78.95 75.2 84.7 78.8 90.71 82.4 96.99 86 103.55 89.6 The issue with trying to use static pressure to determine total charge is that as long as there's enough charge to maintain some liquid refrigerant in the closed system, being at the vapor pressure equilibrium, it will show that same pressure even if additional refrigerant is added. The additional refrigerant will not increase pressure because it remains a liquid when the pressure is at the equilibrium point. The only conclusions you could draw is if the pressure is below the vapor pressure spec at that temperature; that means you're undercharged, with no liquid refrigerant present in the system (assuming it's uncontaminated with other gases or moisture). So it can tell you if it's undercharged, but not if it's overcharged. The 60 PSI shows the system is undercharged, as the shop likely isn't sitting at about 58 deg, since few people would sweat at that temperature.
I thought static pressure was just used to tell if their is a blockage in the system allowing for one side to be a higher pressure then the other? Was never taught to use it to tell if their is refrigerant and how much was in the system.
What is this reference to a "trained eye"? This is extremely basic information, do exactly as the bottle tells you and only measure the pressure with the car running on maximum AC settings. Basic stuff.
Point is many vehicle owners that try to fix their own A/C say yes it has plenty of refrigerant seeing the 60psi for example when in reality this means nothing to the untrained eye that doesn't know the temperature to pressure correlation of R134A.
Most of the DIY equipment instructions specifically tell you to test the pressures while the AC is running. They want to avoid the static pressure situation that is demonstrated, because the concept of varying static pressure based on temperature is too confusing to explain to some people, especially in brief instructions on a can.
Hi Brian. I've got an 06 F150 and the compressor or clutch is "ticking" or "tapping". Is this sound usually due to a worn/faulty clutch or at the compressor? It's still pretty hot on Phoenix right now, so I'd like to get it taken care of before it goes out. Thanks in advance!
You can tell by turning the compressor clutch by hand engine off of course. The compressor should have some resistance as it goes through the compression stroke but should feel smooth. Of course while you are there wiggle the clutch there should be no noise from it.
@@FordTechMakuloco Hi my 2006 mazda 3s 2.3L A/C stops blowing cold after idle slow driving a/c works when im moving traffic fast car doesn't overheat / fans run / ac pressures good / new condenser / new dryer / new a/c clutch / New fans would you know what is my problem is ?
unfortunately anyone can buy the tools and parts without knowing what they are doing.there is a lot to understand with a/c.air flow heat transfer liquid and gas states etc etc. be safe out there . if you are not sure what you are doing maybe its best to leave it to someone who knows.
You do a good job of explaining it. I've watched many of your videos, and mostly the questions that come to me while I'm watching, you answer them. Do you have a video explaining the gage rise and fall readings when a clutch cycles on then back off? Mostly on but my car does alot of off cycles... I don't think it's low on 134a, it seems like a cycling issue, gages don't change readings much.
So my crown Vic recently had a skip on its step, and while I went on a road trip, on the way back it worked fine, on the way back it felt like it wasn’t cooling as well. I tested the temperature, on max fan and ac, it blows between 45 and 55 F (I would assume this is normal temp since the 55 was on a hot day and the 45 was on a slightly cooler day). I tested the pressures and was blowing maybe 25 psi low and 225 psi high on a 74F day, are those numbers normal? The compressor would kick on and off every 5 seconds so the pressures never stabilized but that’s as low (and high) as they went, and I think I might just be over paranoid about my car 😂
Thanks for the video. Question if I may. I have a new to me 2012 ford escape 6cyl. Whenever I turn on the defroster (with heat in the cold NW morning) the ac clutch engages and my radiator fans blast non-stop? I changed the ac pressure switch and symptoms remain. I rented one of those ac gauges and plan to see if there are any red flags, but not 100% sure of what I am looking at/for. Thank you, Scott
2009 Ford Flex. Chasing AC issues. My “can gauge” says I’m charged. I went and loaned this manifold gauge to test it correctly. It’s 77°, 36% humidity. With air on 60°, AC on, dual disabled, rear disabled, FRESH mode: on the Low side I’m at 14-15 psi. High side is 120 psi. With REAR climate on, everything else the same I’m now reading on the low side 34-35 PSI and 150-160 psi on the high side. Which method should I be looking at to get this at the proper charge? Rear climate on or off?
This is a very interesting question, I have a Safari that has rear AC. Regardless if the rear fan is on, it always cycles to the back, thus get the same reading both ways. The REAR numbers look good, did you stick a thermometer in the dash vents to see how cold the air blowing out is?
I got 03 ford ranger blows ice cubes but I don't hear my clutch cycle. is this good or bad. BTW car running is low 35psi high 195, also ac/clutch relay solenoid working
Ford tech makuloco Hi Brian i have a question i have 2013 f150 fx2 just bought it not to long ego it has a noise that is annoying because is really loud it only goes on when the ac is on and the temperature outside (whether) is really hot sometimes it stays on for long time and sometimes only for seconds i took it to the dealer but that day the temperature wasn't hot so the noise was not on and they said it's normal but i have my doubts.
Probably bad bearings in the compressor, it will get louder as time progresses, and the condition of the bearing further deteriorate, eventually the bearings can lock up completely ac causing a loud belt screeching sound.
Maybe you could help me? I just got a 2012 Ford Fusion. It's reading 25 Low side. 250 to 325 high side. The pipe will ice over like snow. What can I do? Are check? Thanks
I'm dealing with a similar situation. There is generally only too causes. A clog in the system somewhere, or not getting enough air flow over the coils. More likely a clog in the r134a system.
Is it normal for ford f150 2014 model for compressor to engage on and disengage off for about less than 2 minutes. With proper charge refrigerant on it. Txv replace and condenser replace. Vent temp about 14celcius Ambient temp 40celcius?
pa5han turn on MAX a/c when recharging. Same as using the recirc. Itll give you more accurate pressures, and cooler air.. Because it circulates air that has already been cooled from the cab.
I have a 2005 expedition and the compressor just won't kick on, didn't show any signs of it going out just one day it stopped kicking on, my system is full. Any tips for getting it working again?
I have what I consider to be an issue about changing out my a/c compressor!! due to the exorbitant "costs" of labor in my area I was wondering if I could replace the compressor at home then take the rv into the mechanic for the complete a/c servive; I have the new compressor(uncharged) and more time then money; how would I replace the old compressor with the new compressor without doing damage to any engine components??? the laborate here is$125hr. the a/c complete service is around $300.00 that price does not include replacing the drier/accumulator and orifice filter; I not a cheap skate (but the costs is ridiculous; I,m just trying to save a buck; my engine is a FORD TRITON V-10 WORKHORSE 415 CU. 6.8LTR GAS/ NATURALLY ASPIRATED ENGINE; THIS IS THE POWER SOURCR FOR MY HOLIDAY RAMBLER RV;; there must be a way to install the new compressor and drive the rv to my mechanic for the a/c service; any suggestions would be greatly appreciated, thank,s GOD BLESS, PATRICK.P
I have a 2001 Ford escape and I think the a/c compressor is going out. I recently tested the A/C system and the static charge was 85 psi. At 80 F ambient temp, The low side read 40 psi at max setting. The high side read 170 psi. the temp from the center vent was 60 F. The compressor also never cycled off. When the fan was set to the lowest setting, the low side pressure dropped to 28 psi and the high side stayed the same and the inside temp dropped to 48 degrees. I did the spin test by hand and there was a couple of spots that had resistance (compression) but otherwise I could spin it with my hand. It did not feel smooth. Do I need to change the receiver/dryer if I replace the compressor and do I need to flush the system out?
So some five years later after this tip was recorded and in a sunny and hot London I attempted to recharge the A/C on our BMW Mini. Using static readings I couldn't get the A/C working and was about to give up. Watched this tip and tried again, was simple to do (clearly the static readings were way off) and all working fine - thank you !!!
If your gauge set does not come with the temperature pressure scale you can go online and get a
r-134a temperature pressure chart and use that for your diagnosis work.
Just what I was originally looking for to understand what was happening. Understanding that there are different pressures depending on whether or not the A/C is running seems crucial for any newbie DIY A/C charging. Wish it was included more on A/C charging vids. Thanks for this great video.
I really appreciate your videos. For several years you have helped keep my old 2010 Focus going like a champ. I do some "easy" work myself, but even for things I don't do myself, it's helped me understand enough that I can communicate effectively with my current mechanic about what my problem is and my theory of what might be broke.
Love your videos BUT it’s definitely not totally worthless because the static check will tell you if you have refrigerant in the system which is a great way to start your T/S. Won’t tell you if it’s a full charge but will tell you if you’re empty.
I watch very many video's on RUclips on many different disciplines. Your video are some of the very best I have seen and extremely educational. You are doing a great service to everyone who watches your videos. Thank so very much.
After you refilled it with 3 oz why would somebody look at the gauges and say they are fine. They showed 60 and 60 static. That is low. Don't need a trained eye for that. Who would say that is good? What it did show was that 3 oz will give you 60 and 60. This does not explain why you should not use static pressure for the initial part of diagnostics. Or am I missing something?
I think you missed it yes.
Put me in that category of missing it. The only thing I get from the video is you need the static pressure chart, which is obvious to most people. It isn’t explained why there’s more to it than that.
I had a 02 expedition come in the other day and it was missing the orifice tube. It almost kicked my butt until one of the senior master techs came and helped me. What got me was that the pressures were pretty good but the low side was a little high around 70. The master tech diagnosed it by putting his hand on the pipe where the orifice goes and said there is no temp difference on either side of the pipe where the orifice tube should be. I put in a new orifice tube and the system worked perfectly. I would like to see a video on how to properly diagnose that problem. Thanks
The low side at 70 was a dead giveaway that is nowhere near ok. Odd concern for sure though but a temp gun is what I would use to check either side of the orifice. In a txv system with a scroll compressor this can be misdiagnosed a weak compressor or failed txv. The expedition uses a standard FS-10 Swashplate compressor and Fixed orifice which is key here it makes it much easier to diagnose.
What does txv mean?
@@ltlpaa2973 , thermal expansion valve.
Good info on the TXV. I was wondering why my AC wouldnt cycle on/off the way my 96 civic did
New to me also. I drive older Miata.
love those compressor control valves that fail and they say you must replace the compressor. Nope just changed the valve on a 2015 festiva for a intermittent no cooling. Works great.
Lot of great videos... i always new abiernt temp affected pressures and one else talks about it. also didnt know the low side not affected by temp...
Checked the static pressure on the jeep. High side read what I expected 117 psi but the low side read 300 psi. Everything is new. I’m thinking the compressor. What do you think. FYI ac does work when until it gets pass 107° at that temp I would expect air in the high 60’s. It’s actually in the low 80’s.
Yea.....ok.....but can the static pressures be trusted?
You just proved that using the static pressure reading is the easiest and most reliable way of checking the charge of an A/C system. Why are you saying the opposite?
I am say never use them unless you know what to look for.
Bottom line is you can't change physics. Same thing that HVAC and low, medium, and high temp refrigeration techs miss all the time.
Moisture in the system always throws techs too... Cannot compress water.
I'm glad I have a trained eye. Static works great.
I'm training my eye, just the left one for now...I'll get the right one trained later.
Do you have a chart that you recommend a guy use for correlation of pressure to temps? I’ve been watching your videos on the diagnostics and I’ve learned a ton, I work for a Deere Dealership and work on Ag equipment. I was able to diagnose a plugged evap thanks to one of your videos.
Thanks for the video!!! I wish I would've been able to see the reading at the end of video. What was it?
Just to be clear. In this scenario your reading 61 lbs static pressure on an undercharged system with an ambient temperature of 86 degrees. So the static pressure is way too low for 86 degrees. It seems to me that with the right gauges or a chart to make sense of the static pressure readings you could tell it's undercharged by the static pressure reading. Is this correct or am I missing something. I'm just now starting to learn. The method I followed was to use the gauges with the engine and the AC running and compare the readings to a chart for R134A auto systems. I didn't pay attention to the static pressures. Thank you for the video.
I'm glad I'm not the only one who noted this. The "untrained eye" must mean not referencing an r-134a temperature/pressure chart. Static pressure alone is not enough but for gross under/over charge conditions, it's a good start I would think
Am curious what if there is no reading during the static pressure test; both gauges reading zero? Tx so much!
So basically check pressure while it's running. Got it.
Good video , straight to the point !!
Great video, thank you. Can't escape Boyles and Charles law. From a firemedic/RN retired
Thank you for the info !!!
Your reading was reflecting the freon PSI did not reflect ambient temp. as the freon was colder then ambient from being drawn in the system. If you would have waited until the freon warmed to ambient temp. reading would match. Noting to do with type of AC system.
not sure what you are complaining about these are static pressures at room temp.
If you aren’t trained, you shouldn’t be handling refrigerant anyway.
Issue im having is the pressures are changing as the Trucks RPM change. All new components but its not cooling. Idle at 55/170 reved to 2000k at around 30/220. Wont cool unless reved or driving. Any ideas?
How about a video on the dual evaporator system. I have a problem with my expedition and I believe the rear txv valve is clogged or stuck.
When you turned on the engine, what is the acceptable pressure on the low (blue side)?
Hello I purchased one of the cheap refrigerant cans and when i first hooked it up to the low side it was not reading on the gauge and the compressor was not on. I began charging it up then the compressor would turn on dropping the reading to nothing then turn off again bringing the reading up to what the gauge say a good charge. but then as soon as the compressor comes back on the gauge pressure would drop. My question is do i charge the system with the compressor on or off?
Yo, if you let the AC run a bit after putting in the 2ozs of Freon, then turn it off and let it stabilize, the static gauges will show very low pressure so, I disagree with this video. Whose gonna squirt 3 ozs of freon in and not run the AC. Who measures a car without first running the AC? I disagree with assessment on static pressure being worthless to the untrained eye.
totally agree.... still useful information about gauges!
I replaced my compressor on a 2011 Explorer XLT and the compressor clutch won't engage. I made sure to oil the new compressor and I charged the system with a full can. The A/C lines in this car is kind of long and runs to the back for the 3rd and 2nd row cooling so I am not sure if it just requires more coolant or no. The relay is fine. I ran some FORscan tests and I got a reading of 910 kPA for the acp_press. No codes either. Have I done something wrong?
TimeHopeFaith Before charging w the can, Did you get a vacuum pump and pull a vacuum on your system down to about 29 inches for about 2 hours? Also, did the can have the exact amount of R134 that your car calls for? There should be a sticker somewhere under the hood that tells how much your system is supposed to have.
You mean to say by static reading we get to know nothing abt the refrigerant whether it is low or high. Only by operating readings give accurate results.
Amazing information! Way better than other videos that just show how to recharge! Thank You!!
Another great tip, keep them coming 👍
I have an issue with my AC I tried charging it and I had to bypass the AC so we can turn on but every time I charged it it blows back the AC outside of the system from the compressor
All good points. Excellent video Brian.
Those charging cans with gauges--mine has printed instructions to start the engine and run the AC on high setting--fan up before connecting the charging hose to the low port. I have taken flak from an auto forum for using the "Can" without acquiring a manifold gauge set to check the system. Presently, after using the "Can," my AC is cold and the temp gauge I inserted into the mid-dash center vent reads about 40F at the hottest point. Definitely great for the past 2 weeks as the weather here is 90+ and very humid. There is mucho sweat on the low side lines under the hood--so much so, it is dripping water. The vehicle is 17 years old so I am not about to put $200-500 into a repair by a shop.
Theres 5 minutes I'll never get back.
ungrateful
2000 mustang gt when the ac is on the clutch doesn’t stay engaged for more than 2 to 3 seconds and the idle is going up and down ,what is wrong any help will be appreciated this is Rick from sf calif
Looking for a video explaining why an ac will blow cold air until engine warms up, then air goes hot. Outside temp doesn’t matter.
Prob bad blend door control. Cause once coolant gets hot inside heater core then hot air blends with cold air. U can try to bypass heater core to determine problem
I wish you were in Houston Texas area...
Question. I have a Dart 2013 my pressures are not equalizing, a guy at the ac shop told me nowadays static pressures not equalizing doesnt mean much. Whats the truth?
i have taken my 2018 F 150 into ford dealership and they could not fix truck. The A/C works great for the most part...but since i owned it (1 Year) the A/C on 5 separate occasions did not work . is there a fix for this
I HAVE A, 2011 FORD ESCAPE ,LOW SIDE IS 125PSI HIGH SIDE 210, THIS IS WHEN RUNNING, I HEARD THE DRYER FROM 08, THROUGH 2011. WILL BURST AND FILL EXPANSION VALVE. WHAT DO YOU THINK.
I have 08 edge and it will not blow cold compressor works its fully charged i changed the expansion valve and the compressor and still no change the line gets frosty when it takes in the refrigerant but after that nothing and it seems like its getting trapped somewhere any tips
i have a motorhome that is short cycling every 2 to 5 seconds with low side at 35 to 45 and the high side is the same with ambient temp at 77. would you start out with replacing compressor. thanks
Those readings seem low. I know your post is 2 years old, and hopefully you got it fixed, but if not, look up an a/c pressure chart for r134a (if that is what the system is running). Next step would be to find why it is losing pressure (a leak somewhere). Your low side pressure is good, but high side is way way too low. If you only had a weak compressor, the low side would also have been high.
I have a 2013 F-250 Super Duty The clutch on the compressor it kicks in for a few minutes then it cuts off in a minute or 2 cut back on The refrigerant is good Any help will be greatly appreciated
Great vid!! Will check out more later for sure! So I guess my system would sit around 60 psi regardless of refrigerant level?
Thankyou for your help! James
What should the gauge read on the low side for a fully charged system with compressor running?
Hey Brian ever use thermocouples to make full system diags with out the use of gauges?
Nope I stick to a regular manifold gauge set they have not let me down yet. Kind of like the power probe everyone talks about for electrical diag still to this day I have not found a need for one.
gotcha, I like using both and I agree on the PP, I am a test light scope kinda guy :)
FordTechMakuloco same here, just use a basic test light and the trusty Fluke. I renamed the Power Probe the module zapper, guys try to activate solenoids and kill control modules in short order by backfeed.
Thermocouples? Huh Gota, look into that never heard of it 🤔👍👍
Sorry to be so off topic but does any of you know of a method to get back into an Instagram account..?
I was dumb forgot the account password. I love any assistance you can give me!
Is it standard procedure to do the service check with engine running at idle or another RPM?
Idle to start with.
2004 F150 4x4 refrigerate liquid line keep bursting off. It will charge and run for about a day and pisssss the hose will blow off near fire wall. I purchased new line also 2, two orifice tubes. I have totally used 9 cans of Freon...Please help !!! Thanks
Interested in this series because I have an issue with my a/c. When I leave my house, no matter what direction, I am up to 50 mph almost immediately so the air works great. I recently spent a few days in the city where I averaged less than 30 mph and my system struggled. After checking with gauges, not sure I need to add more Freon.
Was wondering the cost to purge and refill my system with proper amount? 2006 F150, 5.4
If a refrigerant that changes to liquid at say ( example ) 100 psi then a static system with 2 ounces of liquid refrigerant would have same pressure as same system with 20 ounces of refrigerant at same temperature. Correct?
thanks I'll get it checked.
Hi my name is juan i have questions can’t figure out my 04 xplorer 4.0 sohc replace ac system components my high side has erratic 237 pressure low 35.
How about Engine Cooling Fan Controller-Temperature Switch HAYDEN 3652 could it be this?
I'd like to have seen the gauges after fully charging the system with the correct amount of freon.
Someone said that the static pressures if they are not equal after the vehicle has sat for a period of time that you automatically know that there is a restriction in the system. Is there any merit to that idea?
with a TXV (or other valve) fail, or other contaminant restriction anywhere in the system, the pressure with not equalize as quickly as normal between low and high sides, static.
I had 30 PSI low and 300 PSI high on my 2010 Focus, which may still be overcharged. I had the system way overcharged when I blindly added some leftover R134a without looking at the high side, not realizing the compressor was then driving the high side pressure to the safety cutoff at 435 PSI. AC was ineffective as a result, with the low side only dropping to 60 PSI, not low enough for the expansion valve metered refrigerant gas to expand sufficiently into the evaporator for cooling.
I just put my gauges on a 2006 H3 Hummer, the low side static pressure pegged the gauge, and the high side static pressure was in line, with engine on low side fluctuates from 20 psig to 70 psig, I’m guessing expansion valve, any help would be appreciated
This helped me a ton, thank you!
15 mustang GT. Bought a cheap refill bottle. Clutch isn't engaging, but scared to overfill. Assuming the static pressure is just throwing me off and I can keep adding refrigerant? I added maybe half of a 20oz can. How much do you need to actually trigger the clutch?
Thank you for explaining about the Static Pressure. What would be your opinion about my system. I have static pressure of 135 high and low side with outside temp of 86 with an engine compartment temp of 95 degree and inside car temp of 105 With the car and AC on I have 49 on the low side and 235 high side. I have air vent temp blowing at 68 degrees. My issue is that the compressor seems to cycle a lot when it is hot outside and doesn't constantly stay cold but seems to work great in the mornings or evenings when the outside temp drops down around 75. Electric engine fan is working. Thank you
Vito Lotta my car is doing the same. Trying to figure it out too.
Good Stuff Man! Correct me if I'm wrong please. The static can be used as a general idea based off how ii correlates with the temp. In this video with just 3oz it showed as if the temp in your shop was around 60 degrees. That is the trained eye you're talking about? Where as the first reading indicated the correct 86 degrees using static.
right the system refrigerant must be at ambient such as after a cold soak of 6 hrs or more then static cab be a good general indicator.
I never consciously realized it but static is a good indicator of charge, I’m working on something atm where compressor won’t turn on but pressure, and how it correlates to temperature led me to believe refrigerant was low (also prevent compressor engagement)
I keep seeing that the static pressure in psi of R134 in a properly charged system should basically equal the ambient temp in degF. But in this video, static pressure was 100 psi when ambient was 86deg F. What's up?
@@mrau92me
That only holds around 68 deg F, give or take 5 degrees. When the temperature goes higher, the pressure goes up at a faster rate than the temperature. Similarly, as the temperature goes lower than 68 deg F, the pressure drops more rapidly.
Something like this:
Pressure Degrees Fahrenheit
53.88 57.2
58.43 60.8
63.2 64.4
68.21 68
73.46 71.6
78.95 75.2
84.7 78.8
90.71 82.4
96.99 86
103.55 89.6
The issue with trying to use static pressure to determine total charge is that as long as there's enough charge to maintain some liquid refrigerant in the closed system, being at the vapor pressure equilibrium, it will show that same pressure even if additional refrigerant is added. The additional refrigerant will not increase pressure because it remains a liquid when the pressure is at the equilibrium point.
The only conclusions you could draw is if the pressure is below the vapor pressure spec at that temperature; that means you're undercharged, with no liquid refrigerant present in the system (assuming it's uncontaminated with other gases or moisture).
So it can tell you if it's undercharged, but not if it's overcharged.
The 60 PSI shows the system is undercharged, as the shop likely isn't sitting at about 58 deg, since few people would sweat at that temperature.
@@dtrrtd774 Thank you
I thought static pressure was just used to tell if their is a blockage in the system allowing for one side to be a higher pressure then the other? Was never taught to use it to tell if their is refrigerant and how much was in the system.
Yeah it can give you allot of information.
Excellent video, thank you
What is this reference to a "trained eye"? This is extremely basic information, do exactly as the bottle tells you and only measure the pressure with the car running on maximum AC settings. Basic stuff.
Point is many vehicle owners that try to fix their own A/C say yes it has plenty of refrigerant seeing the 60psi for example when in reality this means nothing to the untrained eye that doesn't know the temperature to pressure correlation of R134A.
Most of the DIY equipment instructions specifically tell you to test the pressures while the AC is running. They want to avoid the static pressure situation that is demonstrated, because the concept of varying static pressure based on temperature is too confusing to explain to some people, especially in brief instructions on a can.
Nice One !! That is the Info I was looking for ...Thank you :)
help me out with this reading please low side 30 high side 425 thanks
Thanks, I may have to look at my '10 F150 it seems a little weak. It never cooled like our '07 escape though, miss that one.
Hi Brian. I've got an 06 F150 and the compressor or clutch is "ticking" or "tapping". Is this sound usually due to a worn/faulty clutch or at the compressor? It's still pretty hot on Phoenix right now, so I'd like to get it taken care of before it goes out. Thanks in advance!
You can tell by turning the compressor clutch by hand engine off of course. The compressor should have some resistance as it goes through the compression stroke but should feel smooth. Of course while you are there wiggle the clutch there should be no noise from it.
+FordTechMakuloco Thanks! Don't know if it is of significance or not, but but the noise only occurs when the compressor is running... Thanks again!
@@FordTechMakuloco Hi my 2006 mazda 3s 2.3L A/C stops blowing cold after idle slow driving a/c works when im moving traffic fast car doesn't overheat / fans run / ac pressures good / new condenser / new dryer / new a/c clutch / New fans would you know what is my problem is ?
unfortunately anyone can buy the tools and parts without knowing what they are doing.there is a lot to understand with a/c.air flow heat transfer liquid and gas states etc etc. be safe out there . if you are not sure what you are doing maybe its best to leave it to someone who knows.
richard cranium Totally agree with you
You do a good job of explaining it. I've watched many of your videos, and mostly the questions that come to me while I'm watching, you answer them. Do you have a video explaining the gage rise and fall readings when a clutch cycles on then back off? Mostly on but my car does alot of off cycles... I don't think it's low on 134a, it seems like a cycling issue, gages don't change readings much.
When the compressor kicks on the high side pumps up and low side drops.
My e450 the high side will not release pressure
Changed ac compressor,low pressure still will not charge...what could be wrong
Excellent thanks.
So my crown Vic recently had a skip on its step, and while I went on a road trip, on the way back it worked fine, on the way back it felt like it wasn’t cooling as well. I tested the temperature, on max fan and ac, it blows between 45 and 55 F (I would assume this is normal temp since the 55 was on a hot day and the 45 was on a slightly cooler day). I tested the pressures and was blowing maybe 25 psi low and 225 psi high on a 74F day, are those numbers normal? The compressor would kick on and off every 5 seconds so the pressures never stabilized but that’s as low (and high) as they went, and I think I might just be over paranoid about my car 😂
What is the normal,fully charged AC system,pressure on the low side and on the high side for all makes and models ? Or it varies from car to car ?
It varies in the type of refrigerant. Google the chart for r134a.
Great video
Thanks for the video. Question if I may. I have a new to me 2012 ford escape 6cyl. Whenever I turn on the defroster (with heat in the cold NW morning) the ac clutch engages and my radiator fans blast non-stop? I changed the ac pressure switch and symptoms remain. I rented one of those ac gauges and plan to see if there are any red flags, but not 100% sure of what I am looking at/for. Thank you, Scott
AC clutch is supposed to engage when you turn on defroster. Radiator fan is temp driven depending on your environmental conditions and auto
2009 Ford Flex. Chasing AC issues. My “can gauge” says I’m charged. I went and loaned this manifold gauge to test it correctly.
It’s 77°, 36% humidity.
With air on 60°, AC on, dual disabled, rear disabled, FRESH mode: on the Low side I’m at 14-15 psi. High side is 120 psi.
With REAR climate on, everything else the same I’m now reading on the low side 34-35 PSI and 150-160 psi on the high side.
Which method should I be looking at to get this at the proper charge? Rear climate on or off?
This is a very interesting question, I have a Safari that has rear AC. Regardless if the rear fan is on, it always cycles to the back, thus get the same reading both ways.
The REAR numbers look good, did you stick a thermometer in the dash vents to see how cold the air blowing out is?
@@OldSchoolNoe I ended up adding more refrigerant and then it started working again.
muchas gracias ,
I got 03 ford ranger blows ice cubes but I don't hear my clutch cycle. is this good or bad. BTW car running is low 35psi high 195, also ac/clutch relay solenoid working
Ford tech makuloco Hi Brian i have a question i have 2013 f150 fx2 just bought it not to long ego it has a noise that is annoying because is really loud it only goes on when the ac is on and the temperature outside (whether) is really hot sometimes it stays on for long time and sometimes only for seconds i took it to the dealer but that day the temperature wasn't hot so the noise was not on and they said it's normal but i have my doubts.
Probably bad bearings in the compressor, it will get louder as time progresses, and the condition of the bearing further deteriorate, eventually the bearings can lock up completely ac causing a loud belt screeching sound.
160 on the high side and 170 on the low. A/c condenser is a little damaged. What do you think?
Sure sounds like a compressor that is not coming on or not pumping.
@@FordTechMakuloco I noticed the AC condenser was damaged. Looks like it got hit by a rock. It's bent near the orifice tube.
@@FordTechMakuloco and its a small SUV. cooling in the front and warm in the back.
THANK YOU FOR THE HELP
Nicely presented. Thank You
I usually charge my system with ac on and full fan
Yup if you use the cans but this is an a/c recovery machine that can forced it in.
thanks
Maybe you could help me? I just got a 2012 Ford Fusion. It's reading 25 Low side. 250 to 325 high side. The pipe will ice over like snow. What can I do? Are check? Thanks
I'm dealing with a similar situation. There is generally only too causes. A clog in the system somewhere, or not getting enough air flow over the coils. More likely a clog in the r134a system.
Hi can u help me out my low side line is extremely hot
Good job my friend Thanks
Is it normal for ford f150 2014 model for compressor to engage on and disengage off for about less than 2 minutes. With proper charge refrigerant on it. Txv replace and condenser replace.
Vent temp about 14celcius
Ambient temp 40celcius?
Miguel Pilapil it’s not normal. Check for clogger filters , evaporator , thermostat . Do u have climate control ?
When recharging the AC system, should recirculation be on or off?
on
Iowa Comm. Watch News Network but why? How does the recirculation flapper position in the cabin influences the recharging process?
pa5han turn on MAX a/c when recharging. Same as using the recirc. Itll give you more accurate pressures, and cooler air.. Because it circulates air that has already been cooled from the cab.
I would keep the re circulation off so the AC works harder.
Can you make a video how to diagnose ac system on a 2006 ford hybrid?
I plan on it.
Great info. Thanks!
I have a 2005 expedition and the compressor just won't kick on, didn't show any signs of it going out just one day it stopped kicking on, my system is full. Any tips for getting it working again?
+NoFearKT Kyle I am shooting that video next it will be much easier to follow than me telling you all the checks to do
+FordTechMakuloco Thanks! Enjoy the videos even when I'm not looking to fix anything
I have what I consider to be an issue about changing out my a/c compressor!! due to the exorbitant "costs" of labor in my area I was wondering if I could replace the compressor at home then take the rv into the mechanic for the complete a/c servive; I have the new compressor(uncharged) and more time then money; how would I replace the old compressor with the new compressor without doing damage to any engine components??? the laborate here is$125hr. the a/c complete service is around $300.00 that price does not include replacing the drier/accumulator and orifice filter; I not a cheap skate (but the costs is ridiculous; I,m just trying to save a buck; my engine is a FORD TRITON V-10 WORKHORSE 415 CU. 6.8LTR GAS/ NATURALLY ASPIRATED ENGINE; THIS IS THE POWER SOURCR FOR MY HOLIDAY RAMBLER RV;; there must be a way to install the new compressor and drive the rv to my mechanic for the a/c service; any suggestions would be greatly appreciated, thank,s GOD BLESS, PATRICK.P
I have a 2001 Ford escape and I think the a/c compressor is going out. I recently tested the A/C system and the static charge was 85 psi. At 80 F ambient temp, The low side read 40 psi at max setting. The high side read 170 psi. the temp from the center vent was 60 F. The compressor also never cycled off. When the fan was set to the lowest setting, the low side pressure dropped to 28 psi and the high side stayed the same and the inside temp dropped to 48 degrees. I did the spin test by hand and there was a couple of spots that had resistance (compression) but otherwise I could spin it with my hand. It did not feel smooth. Do I need to change the receiver/dryer if I replace the compressor and do I need to flush the system out?
I would be looking at the expansion valve. About $15 online.
2004 e350 van a/c not cools on idle 5.4 new compressor condenser any tsb