Fairtax4me Posted June 14, 2015 Share Posted June 14, 2015 Ok. Normally about half a can will go in and then the system pressure should be just high enough to engage the compressor so it can pull in the rest of the can. It does sound like your compressor is cycling, but why the pressure isn't pulling down, I'm not sure. Try running it for another ten minutes or so with the low side valve closed and see if the low side pressure starts to fall. Link to comment Share on other sites More sharing options...
stackman1 Posted June 14, 2015 Author Share Posted June 14, 2015 Ok. Normally about half a can will go in and then the system pressure should be just high enough to engage the compressor so it can pull in the rest of the can. It does sound like your compressor is cycling, but why the pressure isn't pulling down, I'm not sure. Try running it for another ten minutes or so with the low side valve closed and see if the low side pressure starts to fall. FairTax - do you you mean forget about charging the system for a moment and just - attach the manifold hoses to the low and high side shraders - with both gauge valves closed - and run the engine? Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 14, 2015 Share Posted June 14, 2015 Yep, just run it with the guages hooked up for about ten minutes, but don't try to add any more refrigerant. If the low side stays high, or climbs higher, either the compressor is toast or the guages are damaged... or maybe hooked up backwards. Take some pictures of your setup too. Link to comment Share on other sites More sharing options...
stackman1 Posted June 14, 2015 Author Share Posted June 14, 2015 Yep, just run it with the guages hooked up for about ten minutes, but don't try to add any more refrigerant. If the low side stays high, or climbs higher, either the compressor is toast or the guages are damaged... or maybe hooked up backwards. Take some pictures of your setup too. Hooked up gauges this morning. Started Car. A/C on. Opened both Gate Valves on Manifold Gauge Set. After about 20 minutes here is result: Low ~ 84psi; Hi ~ 75psi https://dl.dropboxusercontent.com/u/108322879/Twenty%20Minutes.jpg https://dl.dropboxusercontent.com/u/108322879/Full%20Pic.jpg Link to comment Share on other sites More sharing options...
stackman1 Posted June 14, 2015 Author Share Posted June 14, 2015 Hopefully my dropbox links comes through - The PSI readings reflect charging the system from empty with what feels to be only 1/2 the first 12oz can? Question about Manifold Gauge. I call the valves on the ends - Gate Valves - I think that is more of a plumbing type term. But I visualize, when I turn the valves counter-clockwise I am retracting an internal pin. Assuming that is correct - it is only then that the Dial on top is meaningful - because only then the Dial - via the hose - has clear access to the pressure at the Schrader Valve. Right? Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 14, 2015 Share Posted June 14, 2015 Whenever the couplers are connected to the system the guages will show the system pressure. The hand valves on the manifold do not block that pressure from reaching the guages. Turning the valve all the way in only closes the port leading to the charge hose in the center of the manifold. You can check to make sure the hoses are not clogged by disconnecting both of the couplers from the service ports, the guages should still show system pressure. Remove the yellow charge hose from the manifold. Now slowly open one of the manifold valves to purge the refrigerant from the hose and guage on that side. You should see the guage needle start to drop as the valve is opened. On some manifolds there may be a schrader valve in the port for the charge hose, which you can depress with a small screwdriver to release pressure. (Wear gloves if doing this to prevent frostbite from escaping refrigerant) Bleed the pressure from both hoses to make sure the guages both return to 0. If they do not, crack open the hose fittings where they attach to the manifold to make sure refrigerant pressure can escape the hoses. Check the rubber washer/orings in both ends of the hoses to make sure they're not blocking the hose. Close the valves and reconnect the couplers to the system service ports. The guages should jump back up to system pressure. Make sure the hand valves are closed, reconnect the yellow charge hose to the manifold and the can tap. Open the can tap, and open the low side hand valve on the manifold. Start the engine, turn the AC on and see what it does. If it still doesn't act right, try connecting the guage set to a different vehicle (preferable one which you know the AC works) and see if the guages respond properly on that vehicle. Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 14, 2015 Share Posted June 14, 2015 (edited) this confused me too when I first got gauges. If the valves at the ends of the hoses are open, the gauges ALWAYS read that side's pressure. The manifold valves connect the center hose to the side they control. As said above, if both mani valves were open, both sides can communicate with each other. Should be OK to open both when vacuuming. But no other time. (I think). and yes, the small hose-end valves operate sorta backwards - CW open the schrader, CCW closes the schrader. OOPS - got beat! Edited June 15, 2015 by 1 Lucky Texan Link to comment Share on other sites More sharing options...
stackman1 Posted June 14, 2015 Author Share Posted June 14, 2015 Hey Guys - made some progress. Fairtax - have some questions/observations about your last post. Hopefully you can see the following video: https://dl.dropboxusercontent.com/u/108322879/20150614_140617.mp4 You said: You can check to make sure the hoses are not clogged by disconnecting both of the couplers from the service ports, the guages should still show system pressure. The way I read that you meant disconnect the quick release couplers attached to the high and low side shrader valves. That was not intuitive - especially because when I uncoupled the low side line - the refrigerant started coming out of the shrader valve. I quickly replaced the coupling and noticed the nut above the coupler on the hose had gotten loose. I re-tightened the nut with the coupling on the line - and suspect in doing so re-tightened the low side shrader valve inside the line. I unhooked the high side also but didn't take away anything meaningful from that side. I really was helped by you and Texan's words on the operation of the manifold gauges. When you told me I should unhook the hose from the refrigerant lines in the car , I realized the end of the hose must have a self-closing valve as well and thereby keeps the pressure as you said. And as suggested, I knew anytime I was about to add referigerant - I always briefly purged the central line for air before beginning the charge. Least I was doing that right...... In any case, by virtue of messing with the lines and doing some tightening I suspect - when I restarted the charge I was smiling because the can was finally getting cold as I remember is normally the case when the refrigerant is being accepted by the system. Put the second can on and emptied that and you see the results in the video. Low PSI ~ 33; High PSI ~ 150. I drove the car slowly around town and I will say it is cooler but not sure it is where it needs to be or if it will last.....although it held a complete vacuum before I began so hopefully it will hold. Is it possible it still need more R134a. What would you recommend? I don't leave for two weeks Do my readings suggest I still likely need to add more refrigerant?. I'll drive it a bit tomorrow and let you know but you've been a great help pushing me. Any Thoughts - please chime in Peter Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 15, 2015 Share Posted June 15, 2015 That was not intuitive - especially because when I uncoupled the low side line - the refrigerant started coming out of the shrader valve. Unfortunately those schrader valves stick open occasionally and you have to be mindful of that. If you put two full cans into the system it should be right at or maybe even a little above full charge. The pressures sound good to me. Driving around in town is when the AC is going to do the least cooling. There has to be airflow across the condenser for the system to cool properly. The radiator fans can make it work well enough, but you get the best results when you're driving on the highway doing about 60mph. You'll notice it cooling much better if you take it for a faster/longer drive. When its really hot out the AC system has to work overtime anyway to get the hot iterior cooled down. Think about how hot the dash and the glass and all that gets sitting in the sun. Even with the best AC systems you still won't feel comfortable until all of that starts to cool off, which takes a little while to accomplish when its 90° out. 1 Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 15, 2015 Share Posted June 15, 2015 you might try blasting the dead bees out of the condenser coil. also, if your car has a cabin airfilter, it might be clogged. Link to comment Share on other sites More sharing options...
salemicf Posted June 15, 2015 Share Posted June 15, 2015 I have a 2002 Legacy with AC problems. I have 56,000 miles on it. All my original miles. I need to geit it fixed. Th "O" rings were replace but only held up for 2 weeks before the AC quit. I was quoted $500 to $1000 for the repair. I was also told the dash needs to be removed in order to perform the repair.. I'm hoping it will be worth fixing. Will the cost run higher after the dash is removed? Can the dash be replaced w/o difficulty? I read on this site that the thermosensor may need replacing together with the expansion valve. I am a retiree & don't use my car very much but I live in Las Vegas NV & right now it's 107 degrees. I have also replaced the head gasket. I would appreciate any input on repairing the AC in my 2002 Legacy Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 15, 2015 Share Posted June 15, 2015 It's unusual but not impossible to have a problem at the expansion coil - but, certainly, anytime someone says you need that extensive and pricey amount of work you should consider spending for another diagnosis and 'second opinion' I feel. ask for a shop recommendation in a new thread - maybe someone here knows a good Subaru mech. near Vegas. Link to comment Share on other sites More sharing options...
stackman1 Posted June 15, 2015 Author Share Posted June 15, 2015 Drove it a bit on the highway today. It was fairly cool - at times it seemed to warm then cool again. Got some dripping inside passenger footwell. Not sure if drain tube is clogged or something is icing and thawing. Hopefully it is the former. Dreading the summer in Florida..... Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 16, 2015 Share Posted June 16, 2015 (edited) Dripping water in the floor is usually due to a clogged drain hose for the evaporator box. You will get periods when the air coming through the vents seems to warm because the compressor has to stop running on occasion so the evaporator won't freeze. There is a thermal switch on the evaporator that tells the ECU to turn the compressor off until the core temperature gets back above a certain point. In a perfect world the core would stay at 33°F all the time, the coldest it can be without the moisture in the air freezing. But in the real world the core temperature drops below 32° and the moisture on the core freezes. If it were to continue running, the core would totally ice over and block airflow, then the ice would cause the core to rupture. The thermo switch ensures that doesn't happen by interrupting the compressor when the core gets too cold. So you get a short period of relatively warmer and more humid air through the vents as the core defrosts. One thing that helps is to use the recirculate function. This pulls the already cooled, de-humidified air in the cabin back through the ventilation system, rather than the hot humid air from outside. This means less potential for ice buildup on the evaporator core, and you'll not notice those pauses when the core is defrosting, because the air being drawn into the core is already cool Another thing that will help, especially in Florida, is one of those big fold out sun shades for the windsheild. Keep the sun from shining directly into the car and it takes less time for the AC system to cool the interior. Edited June 16, 2015 by Fairtax4me Link to comment Share on other sites More sharing options...
stackman1 Posted June 16, 2015 Author Share Posted June 16, 2015 FairTax - totally forgot about the re-circulate! Been driving with fresh air constantly warming the cabin. Saw a YouTube where the the guy locates the a/c drain hose and blows compressed air up into the line to free any debris. I suppose I can buy a can of compressed air but for some reason the idea of blowing bad stuff back into the car internals is less than appealing.....maybe if it gets worse. Maybe the re-circulate will do it. You have been a tremendous help between the a/c and my stereo. Thanks Link to comment Share on other sites More sharing options...
Fairtax4me Posted June 16, 2015 Share Posted June 16, 2015 The compressed air idea sounds bad, but if theres a small leaf or something inside the evaporator box covering the drain hole the air will blow it out of the way. There isn't anything in there to hurt, and the air does a good job of desintegrating dust clumps and leaf crud, then they can hopefully drain out with the water the way theyre supposed to. Link to comment Share on other sites More sharing options...
stackman1 Posted July 4, 2015 Author Share Posted July 4, 2015 Hey FairTax - I made it to Florida in a cool car. Not only that but the traffic was not unbearable. I didn't get a chance to blow out my black drain hose before I left. Likely as a result - throughout the trip I was periodically wringing out a very wet towel every couple of hundred miles in the passenger footwell. Luckily I was riding solo. I'm not complaining because I was mostly concerned with getting my a/c running which you were instrumental in........but just have a configuration question. When I began this thread prior to last years trek to Florida I also had no a/c. And I did lots of research and among other things became convinced I needed to replace the expansion valve. It was a b#tch but I did it. I came across a fantastic thread that kind of walked me through the process. http://www.clubwrx.net/forums/general-maintenance-troubleshooting-accidents/141059-its-getting-very-warm-outside-need-c-help.html The message on 6/12/2006 at 9:44pm has a series of pics. The 4th pic in that message shows the expansion valve. Here is my question: 1. The big white plastic piece I assume is the evaporator and under the bottom red arrow is a black tube..... 2. I assume this is the same tube that I would find under the car? 3. Is the idea that it has to be blocked somewhere so it is backing up and coming out where the black tube connects to the white evaporator? Happy Independence Day - let's pray for Fair Taxes Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 4, 2015 Share Posted July 4, 2015 (edited) I don't see the drain tube in any of those photos. The black corrugated hose on the bottom of the blower box is a vent for the blower motor. It provides airflow to the motor to keep it cool. The drain tube sticks out through the firewall. The only good way to get to it is from under the car. Here's a couple pics of it: http://forums.nasioc.com/forums/showthread.php?t=1718109 It's probably in those other pics somewhere and I'm just blind... Edited July 4, 2015 by Fairtax4me Link to comment Share on other sites More sharing options...
stackman1 Posted July 4, 2015 Author Share Posted July 4, 2015 Yes the black pliable rubber hose. In my link pic of the expansion valve - it was the black rubber tube that ran the bottom of the photo underneath the large white plastic piece. When I reach my hand up to where it terminates under the dash - that is where it gets wet. I will lift the hood up and see if I can spot where it comes through the firewall. Didn't realize that - Unfortunately I don't travel with my floor jack and jack stands - getting underneath may be an issue. Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 4, 2015 Share Posted July 4, 2015 If you can get to it from inside, you may be able to pull it in through the grommet in the firewall. Link to comment Share on other sites More sharing options...
stackman1 Posted July 4, 2015 Author Share Posted July 4, 2015 If you can get to it from inside, you may be able to pull it in through the grommet in the firewall. Hopefully this dropbox link works.... I opened the hood and pulled this hose forward a bit....this must be it right? If so I can reach it by leaning into the engine. Maybe just get some compressed air. Next time I run it I'll check to see if it is a drain....sure looks like one! Surprised it is relatively high on firewall.... https://dl.dropboxusercontent.com/u/108322879/IMG_20150704_141048400.jpg Link to comment Share on other sites More sharing options...
stackman1 Posted September 25, 2015 Author Share Posted September 25, 2015 Got through the heat of a Florida summer thanks to the good people of this board - FairTax especially. Recently used compressed air on drain tube and also used a shop vac the reverse way to fix severe dripping issue - my latest a/c issue. Hard to tell if that is fixed yet - think it might be.....but who knows. But incredibly happy I got through the summer. Hard to believe about 5 years ago my dealer told me a needed a new a/c compressor!!! Aside from rust on the undercarriage - it is driving well for a car that just turned 14. Just put tires, exhaust and alternator on - so hopefully I'll get another couple of years..... Anyway - here is the latest question for the board. Lately I have noticed that I often have about three inches of fog at base of windshield. And while the the a/c blows cold and strong initially, it remains cold - but then it seems as if the blower motor stops - because hardly any air gets pushed through the vents - even at top setting. I can hear the fan working so don't believe it is blower motor - just not pushing the air. Thoughts? Thanks Peter Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted September 25, 2015 Share Posted September 25, 2015 does the car have a cabin air filter? might be clogged. or a blend door isn't shifting all the way? Link to comment Share on other sites More sharing options...
stackman1 Posted September 25, 2015 Author Share Posted September 25, 2015 Does my '02 have a 'cabin' air filter.....saw video for a late model sube that showed it behind the glove box. Do i have one? The Haynes manual doesn't reference it??? Link to comment Share on other sites More sharing options...
stackman1 Posted September 25, 2015 Author Share Posted September 25, 2015 Yes - I just found this Youtube: And I remember seeing that while plastic rectangle a couple of years ago when I replaced the a/c expansion valve. My guess it is disgusting - hopefully it exists.....lost of posters say theirs were missing. Link to comment Share on other sites More sharing options...
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