AC is 67psi! Was: So, where do I attach this thing (ac
From : christopher d thompson
Q: on sun 14 sep 2008 095034 -0400 jmc wrote suddenly without warning tom lawrence exclaimed 9/13/2008 912 pm problem is i cant figure out where the low pressure valve is. i see a couple of ports that sort of fit the description but none look like the pic in my chiltons manual. never actually worked on a dakota but on a friends 00 durango the low pressure port was up near the compressor just behind the upper radiator hose. trace the lines from the a/c compressor. the one that runs back towards the firewall and into a canister-looking thing that canister is the accumulator is the low-pressure line and the low pressure port will be in that line. on top of the accumulator is also the low-pressure cut-out switch. depending on how much of a charge is in the system you may need to remove the connector from that switch and short the two terminals of the connector not the switch itself with a paperclip or something else. this will keep the compressor running so you can feed it refrigerant. i actually have said durango sitting out in my driveway sans transmission - but thats a whole nother story so if you want me to take a picture pointing it out i can do that. the other piece of good is that the fitting on the can can only fit on the low pressure port not the high pressure port so theres not much danger in hooking it up wrong. tom thanks for the info. psi is around 67 - at any rate just over 65. so what could be wrong with the system i did note that even with the doors open in sun 75f with 91% humidity ick the system cycled every few seconds - perhaps less than 10 - so i pulled the sensor and it stopped as it should. what i saw to indicate the system cycling was a round plate at the end of the compressor spinning and stopping. assume that was the clutch should more than that plate be moving a quick google indicates too much refrigerant or mechanical repair. the acs history in december summer temps in aus it fairly suddenly started blowing nearly hot air i took it in for servicing it came back with cold air. mechanic said no obvious leak and that theyd added an indicator - dont remember if it was uv color or both. was working fine as the days started getting cooler and i left it to be shipped back in mid-may. if it was dying then i didnt notice. when i got it back i think it was ok but it wasnt long after that we started noticing it was no longer blowing cold air. ive checked what i can see and though i need to check with the uv light when its darker i dont really see any leaks. when it works normally even in the 100f temps in aus we could have it on the 2nd setting and be comfortable once the hot air was blown out of the truck. now its on #4 and were still sweating. there is a major difference in humidity between the two locations - aus was usually less than 20% and often less than 10% humidity. id say the air coming out is around 65f or so - i dont have any way to test it. i really want to avoid taking my truck in if i can. on the other hand i dont want to truly break something by fumbling around where i shouldnt. as always any advice appreciated! jmc was the 67psi while the compressor was running use a paper clip to short the terminals on the low pressure cut-out switch on the accumulator so the compressor stays running while you charge the system. an a/c system that cycles for only a few seconds usually is a low charge. 99% of the time in fact. -- chris .
Replies:
From : jmc
suddenly without warning tom lawrence exclaimed 9/15/2008 930 pm how can i tell when a can is actually empty when you shake the can and cant hear/feel anything anymore. i was sort of afraid something horrible would happen if i drained it past empty nope... all that will happen is the pressure in the low side of the system will equalize with the residual pressure in the can. one that happens you could hold the button down for weeks on end and the only thing youd get would be a sore finger. on the top of the radiator support there should be a label telling you what the charge is for the a/c system. it will be in pounds and ounces or just ounces. compare that with the net weight printed on the can. it can take up to the amount listed on the vehicle sticker depending on how much leaked out. like i said my friends durango took two of the big cans i think 18oz. each or 2lbs. 4oz. professionals would recover all the remaining refrigerant draw the system down to a strong vacuum then recharge by weight. without several hundred dollars in tools and equipment you have to things the way youre doing them. tom do you think i have a leak definitely. what isnt known is how big of a leak. recharging it like youre doing serves two purposes. first it gets it working again and second it lets you identify where the leak is coming from after its run for a few days and the dye has a chance to leak out. once you determine where its leaking you can make an educated guess as to how much its going to cost to fix vs. recharging it now and then when needed. for example if its determined that the evaporator is leaking and you run for 3-4 months before the performance falls off its a pretty tough pill to swallow $800-$1000 vs. $50 per year of recharge cans. however if its coming from a hose fitting and it leaks out after a week its an easy decision the other way maybe $200 total. youll probably fall somewhere in the middle though. wrong or is it just a silly tired non-mechanic fumbling around with a new procedure gaaa i need to make friends with a car hobbyist g well we know somethings wrong - no question about that. this is the process to determine what that is. and youre learning something about your a/c system in the process tom thank you. good thing i bought a kit with two big cans then - the dak and the durango are fairly identical i think so its a fair bet if a durango takes two cans my dakota will too. ill look for the label once the sun comes up. jmc .
From : jmc
suddenly without warning tom lawrence exclaimed 9/15/2008 727 pm finally i stopped. turned the truck off and heard a hissing sound. normal... thats the pressure equalizing between the high and low sides. theres a puddle of something under the truck - will have to wait until also normal - thats condensation off the evaporator. that means the evaporator is getting at least cold enough to wring some moisture out of the air. ok thats what i thought. theres always been a puddle there after running ac so i was pretty sure it was normal. full dark to find out if its refrigerant or condensation. at atmospheric pressure refrigerant is a gas.... so no puddles of r134 ok. it seems to be coming from somewhere behind the firewall right behind the cannister. thats where the condensate drain for the evaporator is located... little rubber elbow coming out of the firewall. so i think i have a leak. pretty major one or does it really take that long to load refrigerant how long should it take several minutes... the pressure in the can isnt that much greater than the normal low-side pressure so it can take a bit. depending on how low it was it could even require more than one can. ok. had a look around in the dark and could see that around the port things glow bright yellow. cool. no refrigerant in the drip. i found small speckles of yellow glow here and there - a seal on the low part of the condenser seems to reflect - not glow - yellow in my cheapie uv pen. a bit of speckle below the low-pressure point more lower down under a bit of electrical or duct tape will check in morning purpose of tape. on the underside of my oil filter though something wet and yellow tho not glowy like around the vent. but definitely yellow in uv thick like oil and forming a drip on the underside of my oil filter. tomorrow ill look in daylight but would oil reflect yellow under uv you already said refrigerant wouldnt drip but would the dye mix with the oil to produce what i saw several minutes - like the 5 i gave it or 10 or 15 and shouldnt the needle have moved more than about two millimeters for 3/4 can of refrigerant basic question how long should it take to load one of those short cans of refrigerant on a low system how much psi should one of those cans add how can i tell when a can is actually empty given the warnings of gloves and safety goggles forgot the gloves dont own safety goggles i was sort of afraid something horrible would happen if i drained it past empty ill try again tomorrow. i dont have a definitive leak but i guess i cant see how there *isnt* one seeing the thing was professionally serviced less than a year ago and at that time they said it was empty. please correct me if im wrong! tom do you think i have a leak do you think anythings actually wrong or is it just a silly tired non-mechanic fumbling around with a new procedure gaaa i need to make friends with a car hobbyist g sorry im asking so many questions. im just one of those folk who has to know all the gorey how and why details when learning something new. jmc .
From : jmc
suddenly without warning christopher d. thompson exclaimed 9/15/2008 514 pm push the ends of the paper clip into the connector on the wiring harness it should stay in place on its own when you do this. the compressor should run. it did. doh. so i hooked up the refrigerant can no pressure really. top edge of a black square in the green. so i pressed the trigger the indicator went halfway down the box. squeeze one minute two minutes. let off pressure. hadnt really moved. long story short at least 5 minutes later i got just a small amount of extra psi into the system maybe just a bit more than the width of the needle but yea the air was colder. im not sure how to tell if the can is empty there was still some frost around the bottom so probably not or how long its supposed to take to empty it. probably emptied about 3/4 of the double-sized can. it has uv dye and sealant supposedly. finally i stopped. turned the truck off and heard a hissing sound. theres a puddle of something under the truck - will have to wait until full dark to find out if its refrigerant or condensation. it seems to be coming from somewhere behind the firewall right behind the cannister. so i think i have a leak. pretty major one or does it really take that long to load refrigerant how long should it take jmc .
From : jmc
suddenly without warning christopher d. thompson exclaimed 9/15/2008 514 pm on mon 15 sep 2008 170550 -0400 jmc wrote suddenly without warning jmc exclaimed 9/14/2008 857 pm suddenly without warning tom lawrence exclaimed 9/14/2008 543 pm ill check again. when the plate at the front of the compressor is not spinning does that indicate the compressor is running or not when the plate isnt spinning the clutch is disengaged. yes short the terminals on the connector you pulled off which will keep the compressor running. then see what your pressure is. the pressure will always read higher when the compressors not running. when the compressors running its pulling sucking refrigerant from the low side compressing it and pumping it out to the high side. thats why the low-pressure line is also referred to as the suction line. it stopped spinning altogether when i took off the low pressure cut-out switch but now i cant be sure. it certainly would. again unbend a small paper clip and shove the ends into the terminals of that connector you pulled off to force the compressor to always run. if it still cycles then there are other issues - like an over-pressure situation caused by either an overcharge highly unlikely as you said it worked fine for a while then degraded... you usually dont accumulate refrigerant over time or a clog in the system usually a gummed-up orifice in the liquid line... but were getting ahead of ourselves here. pull the low-pressure switch connector jumper the terminals hook up the gauge and see what the pressure reads. if it drops low depress the button on the can to dispense refrigerant until you can keep it in the blue. i assume i jumper the terminals while the truck is off then turn it on run ac at max cool and check jmc if the spinning bit at the front of the compressor indicates the compressor is running then - it isnt running when jumpered. with the low-pressure sensor plugged in it cycles every 7 seconds or so. with that sensor removed it doesnt run at all. maybe im doing something wrong. jumpered to me as a computer tech just means ensure that the paperclip touches both terminals at the same time no shoving involved. if it requires something more serious than that then i guess i need to be eddicated oddly it feels a bit colder now that ive been messing around with it a bit. but its also a bit cooler out. now what oh a.a.d.t. gurus g jmc push the ends of the paper clip into the connector on the wiring harness it should stay in place on its own when you do this. the compressor should run. oh. i think i did the wrong bit lol. long day no brain cells left. off to try again. jmc .
From : christopher d thompson
on mon 15 sep 2008 170550 -0400 jmc wrote suddenly without warning jmc exclaimed 9/14/2008 857 pm suddenly without warning tom lawrence exclaimed 9/14/2008 543 pm ill check again. when the plate at the front of the compressor is not spinning does that indicate the compressor is running or not when the plate isnt spinning the clutch is disengaged. yes short the terminals on the connector you pulled off which will keep the compressor running. then see what your pressure is. the pressure will always read higher when the compressors not running. when the compressors running its pulling sucking refrigerant from the low side compressing it and pumping it out to the high side. thats why the low-pressure line is also referred to as the suction line. it stopped spinning altogether when i took off the low pressure cut-out switch but now i cant be sure. it certainly would. again unbend a small paper clip and shove the ends into the terminals of that connector you pulled off to force the compressor to always run. if it still cycles then there are other issues - like an over-pressure situation caused by either an overcharge highly unlikely as you said it worked fine for a while then degraded... you usually dont accumulate refrigerant over time or a clog in the system usually a gummed-up orifice in the liquid line... but were getting ahead of ourselves here. pull the low-pressure switch connector jumper the terminals hook up the gauge and see what the pressure reads. if it drops low depress the button on the can to dispense refrigerant until you can keep it in the blue. i assume i jumper the terminals while the truck is off then turn it on run ac at max cool and check jmc if the spinning bit at the front of the compressor indicates the compressor is running then - it isnt running when jumpered. with the low-pressure sensor plugged in it cycles every 7 seconds or so. with that sensor removed it doesnt run at all. maybe im doing something wrong. jumpered to me as a computer tech just means ensure that the paperclip touches both terminals at the same time no shoving involved. if it requires something more serious than that then i guess i need to be eddicated oddly it feels a bit colder now that ive been messing around with it a bit. but its also a bit cooler out. now what oh a.a.d.t. gurus g jmc push the ends of the paper clip into the connector on the wiring harness it should stay in place on its own when you do this. the compressor should run. -- chris .
From : jmc
suddenly without warning jmc exclaimed 9/14/2008 857 pm suddenly without warning tom lawrence exclaimed 9/14/2008 543 pm ill check again. when the plate at the front of the compressor is not spinning does that indicate the compressor is running or not when the plate isnt spinning the clutch is disengaged. yes short the terminals on the connector you pulled off which will keep the compressor running. then see what your pressure is. the pressure will always read higher when the compressors not running. when the compressors running its pulling sucking refrigerant from the low side compressing it and pumping it out to the high side. thats why the low-pressure line is also referred to as the suction line. it stopped spinning altogether when i took off the low pressure cut-out switch but now i cant be sure. it certainly would. again unbend a small paper clip and shove the ends into the terminals of that connector you pulled off to force the compressor to always run. if it still cycles then there are other issues - like an over-pressure situation caused by either an overcharge highly unlikely as you said it worked fine for a while then degraded... you usually dont accumulate refrigerant over time or a clog in the system usually a gummed-up orifice in the liquid line... but were getting ahead of ourselves here. pull the low-pressure switch connector jumper the terminals hook up the gauge and see what the pressure reads. if it drops low depress the button on the can to dispense refrigerant until you can keep it in the blue. i assume i jumper the terminals while the truck is off then turn it on run ac at max cool and check jmc if the spinning bit at the front of the compressor indicates the compressor is running then - it isnt running when jumpered. with the low-pressure sensor plugged in it cycles every 7 seconds or so. with that sensor removed it doesnt run at all. maybe im doing something wrong. jumpered to me as a computer tech just means ensure that the paperclip touches both terminals at the same time no shoving involved. if it requires something more serious than that then i guess i need to be eddicated oddly it feels a bit colder now that ive been messing around with it a bit. but its also a bit cooler out. now what oh a.a.d.t. gurus g jmc .
From : christopher d thompson
on sun 14 sep 2008 205756 -0400 jmc wrote i assume i jumper the terminals while the truck is off then turn it on run ac at max cool and check jmc it doesnt matter but if it makes you feel better then yes. but it wont hurt anything for you to jumper the low pressure cut-out switch circuit while the vehicle is running. but yes run the a/c on max to check your vent temps. should be somewhere in the neighborhood of 40 deg f at the center vent on a r134a system. -- chris .
From : jmc
suddenly without warning tom lawrence exclaimed 9/14/2008 543 pm ill check again. when the plate at the front of the compressor is not spinning does that indicate the compressor is running or not when the plate isnt spinning the clutch is disengaged. yes short the terminals on the connector you pulled off which will keep the compressor running. then see what your pressure is. the pressure will always read higher when the compressors not running. when the compressors running its pulling sucking refrigerant from the low side compressing it and pumping it out to the high side. thats why the low-pressure line is also referred to as the suction line. it stopped spinning altogether when i took off the low pressure cut-out switch but now i cant be sure. it certainly would. again unbend a small paper clip and shove the ends into the terminals of that connector you pulled off to force the compressor to always run. if it still cycles then there are other issues - like an over-pressure situation caused by either an overcharge highly unlikely as you said it worked fine for a while then degraded... you usually dont accumulate refrigerant over time or a clog in the system usually a gummed-up orifice in the liquid line... but were getting ahead of ourselves here. pull the low-pressure switch connector jumper the terminals hook up the gauge and see what the pressure reads. if it drops low depress the button on the can to dispense refrigerant until you can keep it in the blue. i assume i jumper the terminals while the truck is off then turn it on run ac at max cool and check jmc .
From : jmc
suddenly without warning christopher d. thompson exclaimed 9/14/2008 1147 am on sun 14 sep 2008 095034 -0400 jmc wrote suddenly without warning tom lawrence exclaimed 9/13/2008 912 pm problem is i cant figure out where the low pressure valve is. i see a couple of ports that sort of fit the description but none look like the pic in my chiltons manual. never actually worked on a dakota but on a friends 00 durango the low pressure port was up near the compressor just behind the upper radiator hose. trace the lines from the a/c compressor. the one that runs back towards the firewall and into a canister-looking thing that canister is the accumulator is the low-pressure line and the low pressure port will be in that line. on top of the accumulator is also the low-pressure cut-out switch. depending on how much of a charge is in the system you may need to remove the connector from that switch and short the two terminals of the connector not the switch itself with a paperclip or something else. this will keep the compressor running so you can feed it refrigerant. i actually have said durango sitting out in my driveway sans transmission - but thats a whole nother story so if you want me to take a picture pointing it out i can do that. the other piece of good is that the fitting on the can can only fit on the low pressure port not the high pressure port so theres not much danger in hooking it up wrong. tom thanks for the info. psi is around 67 - at any rate just over 65. so what could be wrong with the system i did note that even with the doors open in sun 75f with 91% humidity ick the system cycled every few seconds - perhaps less than 10 - so i pulled the sensor and it stopped as it should. what i saw to indicate the system cycling was a round plate at the end of the compressor spinning and stopping. assume that was the clutch should more than that plate be moving a quick google indicates too much refrigerant or mechanical repair. the acs history in december summer temps in aus it fairly suddenly started blowing nearly hot air i took it in for servicing it came back with cold air. mechanic said no obvious leak and that theyd added an indicator - dont remember if it was uv color or both. was working fine as the days started getting cooler and i left it to be shipped back in mid-may. if it was dying then i didnt notice. when i got it back i think it was ok but it wasnt long after that we started noticing it was no longer blowing cold air. ive checked what i can see and though i need to check with the uv light when its darker i dont really see any leaks. when it works normally even in the 100f temps in aus we could have it on the 2nd setting and be comfortable once the hot air was blown out of the truck. now its on #4 and were still sweating. there is a major difference in humidity between the two locations - aus was usually less than 20% and often less than 10% humidity. id say the air coming out is around 65f or so - i dont have any way to test it. i really want to avoid taking my truck in if i can. on the other hand i dont want to truly break something by fumbling around where i shouldnt. as always any advice appreciated! jmc was the 67psi while the compressor was running use a paper clip to short the terminals on the low pressure cut-out switch on the accumulator so the compressor stays running while you charge the system. an a/c system that cycles for only a few seconds usually is a low charge. 99% of the time in fact. ill check again. when the plate at the front of the compressor is not spinning does that indicate the compressor is running or not i think it stopped spinning altogether when i took off the low pressure cut-out switch but now i cant be sure. jmc .