Ugh - I think my A/C died yesterday.
06-28-2007, 09:36 AM
#1
Maintenance Monster
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Ugh - I think my A/C died yesterday.
The day before, it was working. Not blasting icy cold, but working. Yesterday morning it was super humid and all I got was a warm air bath. It's a 97 with 170k. The wife is pressing me to dump it, so I have a decision to make.
1) I ran the climate control self-diagnostics per the FSM and all came out clear. Both AC fuses and the relay are good. I've observed the clutch come off/on, so I think that's working. The compressor comes on whenever I run the air, and for a brief minute the air blows a little cool. Then it's just warm air.
From what little I've learned by reading it would seem my refrigerant is all leaked out - correct?
If I try a parts-store r134 A/C recharge kit, will it screw things up if someone tries to fix it properly later? Should I use the leak-stop kind?
2)Is there a way for me to check the high and low pressures safely? Or I am better off paying a shop to do a quick diagnostic?
3) If I tried to do a full A/C overhaul DIY style, I think it could be done like so:
A) discharge system
B) Install all new o-rings and drier
C) Pay A/C shop to vac and charge the system.
**How do I know if I need a new compressor?
Comment welcome.
Dave
1) I ran the climate control self-diagnostics per the FSM and all came out clear. Both AC fuses and the relay are good. I've observed the clutch come off/on, so I think that's working. The compressor comes on whenever I run the air, and for a brief minute the air blows a little cool. Then it's just warm air.
From what little I've learned by reading it would seem my refrigerant is all leaked out - correct?
If I try a parts-store r134 A/C recharge kit, will it screw things up if someone tries to fix it properly later? Should I use the leak-stop kind?
2)Is there a way for me to check the high and low pressures safely? Or I am better off paying a shop to do a quick diagnostic?
3) If I tried to do a full A/C overhaul DIY style, I think it could be done like so:
A) discharge system
B) Install all new o-rings and drier
C) Pay A/C shop to vac and charge the system.
**How do I know if I need a new compressor?
Comment welcome.
Dave
06-28-2007, 10:34 AM
#2
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
The A/C system is pressurized. So unless it is completed leaked out, there should be no air inside.
The 4G A/C system uses a variable capacity compressor (Calsonic CVW-618). The variable capacity feature works on internal pressure only. When the pressure is high, it increases the internal stroke and create more pressure. When the pressure is low, it decrease the stroke to reduce capacity. The triple pressure switch on the dryer/accumulator cuts out the clutch when the high side pressure gets too large to protect the compressor when needed.
Gas do leak out from the various o-rings over time. The working pressure should be around 25-30 PSI on the low side to about 150-200 PSI on the high side. When the ambient temperature is higher, the internal pressure will be higher.
You may simply be low on freon. I would use straight R134a freon only. It should cost $10-$12 for a 12 oz can at Pepboys. It may be a good idea to add oil at the same time. You want to use R134a with 0.2oz PAG46 oil added canisters. The pressure gauge, hose, valve set should be about $50-$80.
Follow the instruction on the gauge package. The total capacity of the 4G A/C system is about 36 oz freon. So you should only need to add no more than one 12 oz can. To avoid getting air in the system, purge the air in the hose with freon from the can after puncturing the can seal.
Fill the system slowly and don't turn the can upside down so the system only suck gas and not liquid freon.
While doing this, keep A/C on max windows open and doors closed.
You may want to review the service manual posted on the forum somewhere. There is a nice high/low pressure diagnostic chart and ambient temperature to gas pressure chart.
My '98 compressor failed a few years ago. Even with a service manual, it took a long time to understand how simple the system really is.
All the electronic stuff don't affect the freon pressurized system directly. They affect it indirectly by blowing warn air over the evaporator and increase internal gas pressure.
The compressor clutch is always on. It gets cut out only when the internal pressure isn't right or the TPS sensor tells the ECM you want more power.
The 4G A/C system uses a variable capacity compressor (Calsonic CVW-618). The variable capacity feature works on internal pressure only. When the pressure is high, it increases the internal stroke and create more pressure. When the pressure is low, it decrease the stroke to reduce capacity. The triple pressure switch on the dryer/accumulator cuts out the clutch when the high side pressure gets too large to protect the compressor when needed.
Gas do leak out from the various o-rings over time. The working pressure should be around 25-30 PSI on the low side to about 150-200 PSI on the high side. When the ambient temperature is higher, the internal pressure will be higher.
You may simply be low on freon. I would use straight R134a freon only. It should cost $10-$12 for a 12 oz can at Pepboys. It may be a good idea to add oil at the same time. You want to use R134a with 0.2oz PAG46 oil added canisters. The pressure gauge, hose, valve set should be about $50-$80.
Follow the instruction on the gauge package. The total capacity of the 4G A/C system is about 36 oz freon. So you should only need to add no more than one 12 oz can. To avoid getting air in the system, purge the air in the hose with freon from the can after puncturing the can seal.
Fill the system slowly and don't turn the can upside down so the system only suck gas and not liquid freon.
While doing this, keep A/C on max windows open and doors closed.
You may want to review the service manual posted on the forum somewhere. There is a nice high/low pressure diagnostic chart and ambient temperature to gas pressure chart.
My '98 compressor failed a few years ago. Even with a service manual, it took a long time to understand how simple the system really is.
All the electronic stuff don't affect the freon pressurized system directly. They affect it indirectly by blowing warn air over the evaporator and increase internal gas pressure.
The compressor clutch is always on. It gets cut out only when the internal pressure isn't right or the TPS sensor tells the ECM you want more power.
06-28-2007, 10:40 AM
#3
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
For the last question, yes, I have a shop in Santa Clara who is willing to evacuate the system and recharge for me. They have equipment to store the freon oil mix temporarily and not having to dump it every time the system is opened.
There are a very places on the web that carry new OE parts. I got my new Calsonic compressor from Meridian Auto Parts in San Diego. There are cheaper places than Meridian also. I would avoid reman. parts.
The pressure check can tell you whether the compressor is bad.
There are a very places on the web that carry new OE parts. I got my new Calsonic compressor from Meridian Auto Parts in San Diego. There are cheaper places than Meridian also. I would avoid reman. parts.
The pressure check can tell you whether the compressor is bad.
06-28-2007, 11:14 AM
#4
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Posts: n/a
SVI30 gave a good write up. I'll add:
1) first - check the system pressure as described in the FSM. I used this gauge kit ($23) and it worked well... http://www.partsamerica.com/ProductD...egoryCode=3569
or you can get a pro set on ebay for about $50.
2) if you are way low the compressor should automatically disengage. I'm wondering if this is working for you.
3) as SVI said, try to find some R134a with PAG oil in it (do NOT use polyol ester). I could not find a can of just R134a and PAG, so I used the interdynamics "arctic freeze" product that had PAG but also had conditioners and a performance booster, etc. I have since been informed that such cans can be harmful to AC system. so far I've not had a problem, but it has only been 2 years.
4) the PAG oil in most DIY kits is PAG100, which is thicker than the nissan spec PAG46. from my research I've learned that it should be ok for top-ups. you just don't want to mix PAG and POE.
5) to fix this right you should really add some UV dye to find the leak, fix the leak, and then get a professional evac & recharge. or you can just keep adding R134+PAG every year until you decide to sell the car.
1) first - check the system pressure as described in the FSM. I used this gauge kit ($23) and it worked well... http://www.partsamerica.com/ProductD...egoryCode=3569
or you can get a pro set on ebay for about $50.
2) if you are way low the compressor should automatically disengage. I'm wondering if this is working for you.
3) as SVI said, try to find some R134a with PAG oil in it (do NOT use polyol ester). I could not find a can of just R134a and PAG, so I used the interdynamics "arctic freeze" product that had PAG but also had conditioners and a performance booster, etc. I have since been informed that such cans can be harmful to AC system. so far I've not had a problem, but it has only been 2 years.
4) the PAG oil in most DIY kits is PAG100, which is thicker than the nissan spec PAG46. from my research I've learned that it should be ok for top-ups. you just don't want to mix PAG and POE.
5) to fix this right you should really add some UV dye to find the leak, fix the leak, and then get a professional evac & recharge. or you can just keep adding R134+PAG every year until you decide to sell the car.
06-28-2007, 11:36 AM
#5
Originally Posted by SVI30
The A/C system is pressurized. So unless it is completed leaked out, there should be no air inside.
The 4G A/C system uses a variable capacity compressor (Calsonic CVW-618). The variable capacity feature works on internal pressure only. When the pressure is high, it increases the internal stroke and create more pressure. When the pressure is low, it decrease the stroke to reduce capacity. The triple pressure switch on the dryer/accumulator cuts out the clutch when the high side pressure gets too large to protect the compressor when needed.
Gas do leak out from the various o-rings over time. The working pressure should be around 25-30 PSI on the low side to about 150-200 PSI on the high side. When the ambient temperature is higher, the internal pressure will be higher.
You may simply be low on freon. I would use straight R134a freon only. It should cost $10-$12 for a 12 oz can at Pepboys. It may be a good idea to add oil at the same time. You want to use R134a with 0.2oz PAG46 oil added canisters. The pressure gauge, hose, valve set should be about $50-$80.
Follow the instruction on the gauge package. The total capacity of the 4G A/C system is about 36 oz freon. So you should only need to add no more than one 12 oz can. To avoid getting air in the system, purge the air in the hose with freon from the can after puncturing the can seal.
Fill the system slowly and don't turn the can upside down so the system only suck gas and not liquid freon.
While doing this, keep A/C on max windows open and doors closed.
You may want to review the service manual posted on the forum somewhere. There is a nice high/low pressure diagnostic chart and ambient temperature to gas pressure chart.
My '98 compressor failed a few years ago. Even with a service manual, it took a long time to understand how simple the system really is.
All the electronic stuff don't affect the freon pressurized system directly. They affect it indirectly by blowing warn air over the evaporator and increase internal gas pressure.
The compressor clutch is always on. It gets cut out only when the internal pressure isn't right or the TPS sensor tells the ECM you want more power.
The 4G A/C system uses a variable capacity compressor (Calsonic CVW-618). The variable capacity feature works on internal pressure only. When the pressure is high, it increases the internal stroke and create more pressure. When the pressure is low, it decrease the stroke to reduce capacity. The triple pressure switch on the dryer/accumulator cuts out the clutch when the high side pressure gets too large to protect the compressor when needed.
Gas do leak out from the various o-rings over time. The working pressure should be around 25-30 PSI on the low side to about 150-200 PSI on the high side. When the ambient temperature is higher, the internal pressure will be higher.
You may simply be low on freon. I would use straight R134a freon only. It should cost $10-$12 for a 12 oz can at Pepboys. It may be a good idea to add oil at the same time. You want to use R134a with 0.2oz PAG46 oil added canisters. The pressure gauge, hose, valve set should be about $50-$80.
Follow the instruction on the gauge package. The total capacity of the 4G A/C system is about 36 oz freon. So you should only need to add no more than one 12 oz can. To avoid getting air in the system, purge the air in the hose with freon from the can after puncturing the can seal.
Fill the system slowly and don't turn the can upside down so the system only suck gas and not liquid freon.
While doing this, keep A/C on max windows open and doors closed.
You may want to review the service manual posted on the forum somewhere. There is a nice high/low pressure diagnostic chart and ambient temperature to gas pressure chart.
My '98 compressor failed a few years ago. Even with a service manual, it took a long time to understand how simple the system really is.
All the electronic stuff don't affect the freon pressurized system directly. They affect it indirectly by blowing warn air over the evaporator and increase internal gas pressure.
The compressor clutch is always on. It gets cut out only when the internal pressure isn't right or the TPS sensor tells the ECM you want more power.
06-28-2007, 01:22 PM
#6
I agree good post!
Here's my experience...on my '95 (498,000kms), my A/C didn't work on the first warm day here in Toronto. It has always worked previous years, so i was prepared for the worst. I talked to my mechanic who was out of freon and he told me to give the DIY kit a try. I bought a kit that contained 2 cans of r12a & 1 sealer + hose. The kit also contained a little tester to analyze whether you needed oil or not. Here's the link :
http://www.redtek.com/index.html#
I talked to the counter person and he told me I should use the sealer, then add the r12a can while checking how cold the A/C felt, taking care not to get it too cold or the Evaporator would freeze.
I was a little skeptical since my compressor was not coming on at all. However, I added the sealer with the car off as advised, and when the compressor clicked on when I started the car & put the a/c on, so I added most of the can of r12a and now A/C works great. So my freon was low, and I'm hoping it's a slow leak that the sealer will fix. Another good thing about this r21a is it's supposedly easier on the compressor & enviro-friendly. I do notice there seems to be less of a performance hit when I turn on the A/C now.
Kit costs $80CAD, I figure if it lasts a couple of years, it's worth it. I got a quote from a local auto chain & they quoted me $80 just to test it, which is not bad, however if they find the problem & I don't agree to get it fixed, they would have to drain out and freon & "seal up the A/C lines". I took my chances on this.
Hope this helps!
Here's my experience...on my '95 (498,000kms), my A/C didn't work on the first warm day here in Toronto. It has always worked previous years, so i was prepared for the worst. I talked to my mechanic who was out of freon and he told me to give the DIY kit a try. I bought a kit that contained 2 cans of r12a & 1 sealer + hose. The kit also contained a little tester to analyze whether you needed oil or not. Here's the link :
http://www.redtek.com/index.html#
I talked to the counter person and he told me I should use the sealer, then add the r12a can while checking how cold the A/C felt, taking care not to get it too cold or the Evaporator would freeze.
I was a little skeptical since my compressor was not coming on at all. However, I added the sealer with the car off as advised, and when the compressor clicked on when I started the car & put the a/c on, so I added most of the can of r12a and now A/C works great. So my freon was low, and I'm hoping it's a slow leak that the sealer will fix. Another good thing about this r21a is it's supposedly easier on the compressor & enviro-friendly. I do notice there seems to be less of a performance hit when I turn on the A/C now.
Kit costs $80CAD, I figure if it lasts a couple of years, it's worth it. I got a quote from a local auto chain & they quoted me $80 just to test it, which is not bad, however if they find the problem & I don't agree to get it fixed, they would have to drain out and freon & "seal up the A/C lines". I took my chances on this.
Hope this helps!
06-28-2007, 02:11 PM
#7
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Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Originally Posted by 95bluse
.... r12a & 1 sealer + hose. The kit also contained a little tester to analyze whether you needed oil or not. Here's the link :
http://www.redtek.com/index.html#
...
http://www.redtek.com/index.html#
...
This HC (hydrocarbon) material did not make it to replace R12 CFC originally due to flammability issues (click on the Material Safety hyperlink in the R12a web page). Although it may be better than R134a for specific heat (thermal capacity), with R134a widely available in retail; there is really no reason to mix the gas in the system.
The PAG46 oil in the Calsonic system is sensitive to reaction from other material also (not hydrocarbons).
http://www.autofrost.com/hotshot/index.html
06-28-2007, 02:50 PM
#8
Originally Posted by SVI30
This HC (hydrocarbon) material did not make it to replace R12 CFC originally due to flammability issues (click on the Material Safety hyperlink in the R12a web page). Although it may be better than R134a for specific heat (thermal capacity), with R134a widely available in retail; there is really no reason to mix the gas in the system.
The PAG46 oil in the Calsonic system is sensitive to reaction from other material also (not hydrocarbons).
http://www.autofrost.com/hotshot/index.html
The PAG46 oil in the Calsonic system is sensitive to reaction from other material also (not hydrocarbons).
http://www.autofrost.com/hotshot/index.html
. Anyway, R134a is hard to find off-the-shelf here in Canada, so I opted for what was the best alternative.
06-28-2007, 04:18 PM
#9
I am in the middle of replacing my condenser and drier right now. I bought http://www.harborfreight.com/cpi/cta...emnumber=92649
which were a good deal, and I am going to make a vacuum pump out of a old refridgerator compressor.
If you want to start fresh, and not just top the system off, then have the system evactuated, and vacuum it down (make sure it holds vacuum for) to get all air and moisture out, then charge with the correct amount of R134, don't rely soley on the pressure readings while charging.
I would not use any "stop leak" products, and you can find pure R134 with no additional substances in it, try Wal-Mart.
With the proper gauges, you can succesfully diagnois/fix your A/C and it will be MUCH cheaper than any shop doing the work since they charge so much since it is a specialty.
which were a good deal, and I am going to make a vacuum pump out of a old refridgerator compressor.
If you want to start fresh, and not just top the system off, then have the system evactuated, and vacuum it down (make sure it holds vacuum for) to get all air and moisture out, then charge with the correct amount of R134, don't rely soley on the pressure readings while charging.
I would not use any "stop leak" products, and you can find pure R134 with no additional substances in it, try Wal-Mart.
With the proper gauges, you can succesfully diagnois/fix your A/C and it will be MUCH cheaper than any shop doing the work since they charge so much since it is a specialty.
06-28-2007, 05:18 PM
#10
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Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Originally Posted by buzpuck11
...
With the proper gauges, you can succesfully diagnois/fix your A/C and it will be MUCH cheaper than any shop doing the work since they charge so much since it is a specialty.
With the proper gauges, you can succesfully diagnois/fix your A/C and it will be MUCH cheaper than any shop doing the work since they charge so much since it is a specialty.
I totally agree that no one else care about your car more than you do. DIY is the best. Even getting everything, compressor, dryer, expansion valve replaced all at once; it will still be way cheaper and be assured that it will be done right.
06-28-2007, 08:41 PM
#11
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Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Originally Posted by 95bluse
I'm aware of the flammabilty issue, there are 2 sides to every story. Apparently Dupont has a big interest in having a stanglehold on R134a . Anyway, R134a is hard to find off-the-shelf here in Canada, so I opted for what was the best alternative.
. Anyway, R134a is hard to find off-the-shelf here in Canada, so I opted for what was the best alternative.http://jzhg.en.ec21.com/GC01939999/C...000/R134a.html
06-28-2007, 11:04 PM
#12
I agree with SVI30 don't mix the refrigerants they both have different boiling points and mixing them will gets you fluctuating pressures due to the diff boiling points and act like a contaminant in your system. buzpuck is also correct don't use a "stop leak" product it's a temporary fix that'll prob cost more when u have to get the job done correctly. R12 (cfc) is a contaminant to our ozone- R134a is "supposedly" safer for our environment we'll let the scientists decipher that, as for r12a this is the first time i've heard of it I'm not sure if it's available in the U.S.. And as for Dupont having a strangle hold? I'm not sure this is true because there are many chemical companies making it, Dupont's freon is a name brand, the refrigerant r134a or r12 is just that a refrigerant, there are many different types of refrigerant for different types of applications, r134a is just the one automotive companies decided to go with for automotive application. Even tho they don't have the same boiling point (why it doesn't blow as cold as r12 because less heat is picked up) they are closer to each other in all aspects. R134a is less efficient than R12 but that was the sacrifice for our environment.
06-29-2007, 09:33 AM
#13
Maintenance Monster
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Thanks for the input everyone.
I picked up a fill kit with pressure gauge, fill valve and hose, and a 14-oz canister of R134 with lubricant and some leak-stop that is supposed to not screw things up. I searched the package up and down to see if the lubricant was PAG, but it didn't say. I believe PAG is pretty much the standard, correct?
I would have preferred to buy the R134 plain and a separate can of PAG oil, but they didn't have that.
Dave
I picked up a fill kit with pressure gauge, fill valve and hose, and a 14-oz canister of R134 with lubricant and some leak-stop that is supposed to not screw things up. I searched the package up and down to see if the lubricant was PAG, but it didn't say. I believe PAG is pretty much the standard, correct?
I would have preferred to buy the R134 plain and a separate can of PAG oil, but they didn't have that.
Dave
06-29-2007, 02:47 PM
#15
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Thanks again everyone for the help.
I tested the low side pressure and it's at 67psi. I did not fill with the kit bottle, obviously. So it's not a lack of fill causing my problem.
Where does this leave me? Is my compressor ok? (I see that as the big ticket item)
Dave
I tested the low side pressure and it's at 67psi. I did not fill with the kit bottle, obviously. So it's not a lack of fill causing my problem.
Where does this leave me? Is my compressor ok? (I see that as the big ticket item)
Dave
06-29-2007, 03:07 PM
#16
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Join Date: Jan 2006
Location: Silicon Valley
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Originally Posted by dgeesaman
Thanks again everyone for the help.
I tested the low side pressure and it's at 67psi. I did not fill with the kit bottle, obviously. So it's not a lack of fill causing my problem.
Where does this leave me? Is my compressor ok? (I see that as the big ticket item)
Dave
I tested the low side pressure and it's at 67psi. I did not fill with the kit bottle, obviously. So it's not a lack of fill causing my problem.
Where does this leave me? Is my compressor ok? (I see that as the big ticket item)
Dave
The bottom of the evaporator box can be opened without detaching both sides, fan box on the right and diverter box on the left. See if the valve or the pipes near the evaporator are frosted over. The valve will be frosted if the valve is stuck open.
This is the cheapest NEW compressor I can find on the web:
http://www.autoairplus.com/category_s/3645.htm
I bought my compressor here, it said Meridian Brand but came as a Calsonic with Nissan markings, about $370:
http://www.meridianautoparts.com/add.../60-00804.html
It is best to replace the dryer/accumulator and the expansion valve at the same time. Then ask someone to evacuate and charge it. Remember to install all new o-rings and I got them at the dealer. The dryer/accumulator at the dealer is about $100.
Castrol sells a 8 oz PAG46 oil bottle and it takes 7-8 oz to fill a new compressor. R134a is a green house gas like CO2 so does contribute to global warming when released into the atmosphere.
06-29-2007, 03:22 PM
#17
Originally Posted by SVI30
For the last question, yes, I have a shop in Santa Clara who is willing to evacuate the system and recharge for me. They have equipment to store the freon oil mix temporarily and not having to dump it every time the system is opened.
There are a very places on the web that carry new OE parts. I got my new Calsonic compressor from Meridian Auto Parts in San Diego. There are cheaper places than Meridian also. I would avoid reman. parts.
The pressure check can tell you whether the compressor is bad.
There are a very places on the web that carry new OE parts. I got my new Calsonic compressor from Meridian Auto Parts in San Diego. There are cheaper places than Meridian also. I would avoid reman. parts.
The pressure check can tell you whether the compressor is bad.
06-29-2007, 04:43 PM
#18
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I didn't put my gauge on the high side since it's just for testing the low pressure side. I would need to buy one just for that purpose.
I tried to remove the lower cover from the cooling unit and could only manage to pry it partly open from the front. The aluminum hose toward the front of the evaporator was ambient temp. The rear aluminum hose was unreachable but didn't look frosted or anything.
I also listened to the car idling and I can definitely hear a slightly different sound coming from the belt area, quite possibly the compressor. It's a very soft slow whirra-whirra like a worn bearing or something.
David
I tried to remove the lower cover from the cooling unit and could only manage to pry it partly open from the front. The aluminum hose toward the front of the evaporator was ambient temp. The rear aluminum hose was unreachable but didn't look frosted or anything.
I also listened to the car idling and I can definitely hear a slightly different sound coming from the belt area, quite possibly the compressor. It's a very soft slow whirra-whirra like a worn bearing or something.
David
06-29-2007, 04:56 PM
#19
It could be the valve seals inside the compressor that failed. If those go out you wont have compression (hence the name 'compressor') and it wont pump the refrigerant through the system. I've had this happen to 2 of my Maxima's.
06-29-2007, 05:54 PM
#20
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Location: Silicon Valley
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Originally Posted by dgeesaman
I didn't put my gauge on the high side since it's just for testing the low pressure side. I would need to buy one just for that purpose.
I tried to remove the lower cover from the cooling unit and could only manage to pry it partly open from the front. The aluminum hose toward the front of the evaporator was ambient temp. The rear aluminum hose was unreachable but didn't look frosted or anything.
I also listened to the car idling and I can definitely hear a slightly different sound coming from the belt area, quite possibly the compressor. It's a very soft slow whirra-whirra like a worn bearing or something.
David
I tried to remove the lower cover from the cooling unit and could only manage to pry it partly open from the front. The aluminum hose toward the front of the evaporator was ambient temp. The rear aluminum hose was unreachable but didn't look frosted or anything.
I also listened to the car idling and I can definitely hear a slightly different sound coming from the belt area, quite possibly the compressor. It's a very soft slow whirra-whirra like a worn bearing or something.
David
Check the high side to make sure. I can't do any attachments yet so send me a PM and I'll send you the diagnostic charts from the FSM.
06-29-2007, 10:57 PM
#22
Originally Posted by dgeesaman
Thanks again everyone for the help.
I tested the low side pressure and it's at 67psi. I did not fill with the kit bottle, obviously. So it's not a lack of fill causing my problem.
Where does this leave me? Is my compressor ok? (I see that as the big ticket item)
Dave
I tested the low side pressure and it's at 67psi. I did not fill with the kit bottle, obviously. So it's not a lack of fill causing my problem.
Where does this leave me? Is my compressor ok? (I see that as the big ticket item)
Dave
p.s.- if your high/low side pressure is too high check ur evap it could be blocked (mildew or debris)this also affects expansion valve function and pressure. look at condenser just 4 kicks--> a restricted evap= high low side press, restricted condenser=high high side press or receiver.
06-30-2007, 09:37 AM
#24
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Originally Posted by dgeesaman
Yes the system was running when I checked it.
Right now I'm planning to buy a used compressor and new drier and have a pro do the drain/refill.
Dave
Right now I'm planning to buy a used compressor and new drier and have a pro do the drain/refill.
Dave
If you do replace it with a used one, drain the old compressor from your car and measure the oil that came out (x oz). Then drain the used one of oil and fill it with with new oil in the amount that came out of the old compressor (x oz). This procedure is in the FSM. Liquid tank replacement is add 0.2 oz and new freon is add 1.1 oz.
New compressor from Calsonic is shipped dry.
06-30-2007, 09:47 AM
#25
Newbie - Just Registered
Join Date: Jun 2007
Posts: 2
I'm having a similar issue
The blower motor went bad on my '96 maxima and I purchased the part from Autozone and replaced the motor. The a/c is very cool, however there isn't enough pressure in the air. It's more like the setting is on low, when in fact it is on high.
06-30-2007, 06:24 PM
#27
Supporting Maxima.org Member
Join Date: Oct 2004
Posts: 44
Filled a/c today and worked great for a couple of hours. Now blows warm air until I jump it from the a/c clutch plug. The compressor only comes on when I jump it, is this the triple pressure switch at fault, also low side was at 90psi
06-30-2007, 06:36 PM
#28
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Originally Posted by ckymaxx
Filled a/c today and worked great for a couple of hours. Now blows warm air until I jump it from the a/c clutch plug. The compressor only comes on when I jump it, is this the triple pressure switch at fault, also low side was at 90psi
07-04-2007, 03:42 PM
#29
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
I got everything back together last Tuesday. The car went down to Long Beach and back over the weekend with no problem and it went up to 100 degrees here today.
I hope this new compressor will hold up a while.
I hope this new compressor will hold up a while.
07-04-2007, 05:35 PM
#30
Maintenance Monster
Thread Starter
iTrader: (10)
Join Date: Jul 2001
Location: Harrisburg, PA
Posts: 3,234
Did the new compressor you linked to come with a new clutch?
I still haven't done much on this yet - my next step is to get the system fully discharged. Thankfully it's not been as hot as normal lately.
Dave
I still haven't done much on this yet - my next step is to get the system fully discharged. Thankfully it's not been as hot as normal lately.
Dave
07-05-2007, 07:54 AM
#31
Great info in this thread. Here's my problem:
Bought my car early 2004, A/C didn't work. Had it looked at by dealer and they refilled it but couldn't find a leak (tech was idiot). A/C worked for a few weeks, then stopped working again. A smarter tech found the leak to be at or near the compressor (UV dye). I didn't want to pay $900 for a new compressor from the dealer so I haven't done anything since.
I'm thinking of trying the sealant method 95bluse mentioned in post #6, but I would just use R134a as the refrigerant. I only drive my car a few days a week and I only use the A/C if it's unbearably hot and humid. It just doesn't make sense for me to spend $300 on a compressor alone and then all the other parts and labor. It's only July and August that I want the A/C. So although it's certainly not ideal, I thought it would be worth a try to see if it lasts for another month or two...repeat the process next summer if it still leaks. Is it safe to say that my compressor is just leaking (maybe the O-ring) and otherwise is working? For the few weeks that the system was charged, it blew cold air just fine.
Bought my car early 2004, A/C didn't work. Had it looked at by dealer and they refilled it but couldn't find a leak (tech was idiot). A/C worked for a few weeks, then stopped working again. A smarter tech found the leak to be at or near the compressor (UV dye). I didn't want to pay $900 for a new compressor from the dealer so I haven't done anything since.
I'm thinking of trying the sealant method 95bluse mentioned in post #6, but I would just use R134a as the refrigerant. I only drive my car a few days a week and I only use the A/C if it's unbearably hot and humid. It just doesn't make sense for me to spend $300 on a compressor alone and then all the other parts and labor. It's only July and August that I want the A/C. So although it's certainly not ideal, I thought it would be worth a try to see if it lasts for another month or two...repeat the process next summer if it still leaks. Is it safe to say that my compressor is just leaking (maybe the O-ring) and otherwise is working? For the few weeks that the system was charged, it blew cold air just fine.
07-05-2007, 08:02 AM
#32
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Could be just the o-rings. A/C shop can store the refrigerant, replace the o-rings, evacuate, then put back the refrigerant all in one sitting.
Did the dye came out towards the clutch or the tail end near the hose connections?
Did the dye came out towards the clutch or the tail end near the hose connections?
07-05-2007, 12:46 PM
#33
Supporting Maxima.org Member
iTrader: (54)
Join Date: Feb 2001
Location: Northern Jersey
Posts: 10,166
Originally Posted by SVI30
32oz.
This site sais 24oz http://www.sadik.net/nissan/howto/ac_r134.htm
-matt
07-05-2007, 04:05 PM
#35
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Matty, You are correct, I checked the FSM and it lists 1.43LB which is 23 oz. (21-25 oz)
The ambient to high-low side pressure listed in the FSM are as following:
25degC (77degF), 142-189PSI, 20-24PSI
35degC(95degF), 199-263PSI, 23-27PSI
Relative humidity at 50-70%
Test conditions are as following:
Doors closed
Windows open
Temp set: MAX, COLD
RECIRC switch: ON
Engine speed: 1500RPM
Operate the A/C system for 10 minutes then test the pressure
The ambient to high-low side pressure listed in the FSM are as following:
25degC (77degF), 142-189PSI, 20-24PSI
35degC(95degF), 199-263PSI, 23-27PSI
Relative humidity at 50-70%
Test conditions are as following:
Doors closed
Windows open
Temp set: MAX, COLD
RECIRC switch: ON
Engine speed: 1500RPM
Operate the A/C system for 10 minutes then test the pressure
07-05-2007, 06:58 PM
#36
Originally Posted by dgeesaman
Did the new compressor you linked to come with a new clutch?
I still haven't done much on this yet - my next step is to get the system fully discharged. Thankfully it's not been as hot as normal lately.
Dave
I still haven't done much on this yet - my next step is to get the system fully discharged. Thankfully it's not been as hot as normal lately.
Dave
Anyone know long can you let it go empty before you really start screwing seals up and the like?
07-05-2007, 07:10 PM
#37
Originally Posted by SVI30
Could be just the o-rings. A/C shop can store the refrigerant, replace the o-rings, evacuate, then put back the refrigerant all in one sitting.
Did the dye came out towards the clutch or the tail end near the hose connections?
Did the dye came out towards the clutch or the tail end near the hose connections?
Originally Posted by 97SEdriver
Anyone know long can you let it go empty before you really start screwing seals up and the like?
But even at zero pressure there must still be some refrigerant in the system since it wasn't evacuated.
07-05-2007, 07:49 PM
#38
Senior Member
Join Date: Jan 2006
Location: Silicon Valley
Posts: 655
Originally Posted by dgeesaman
Did the new compressor you linked to come with a new clutch?
I still haven't done much on this yet - my next step is to get the system fully discharged. Thankfully it's not been as hot as normal lately.
Dave
I still haven't done much on this yet - my next step is to get the system fully discharged. Thankfully it's not been as hot as normal lately.
Dave
07-18-2007, 03:04 PM
#39
Maintenance Monster
Thread Starter
iTrader: (10)
Join Date: Jul 2001
Location: Harrisburg, PA
Posts: 3,234
So I finally got it diagnosed. At first they thought I only needed a new expansion valve (and drier), but it didn't blow very cold air afterward and the compressor didn't seem to be working 100%.
So I need a new compressor, and rather than paying them $550 for a reman compressor at full retail, the shop discharged it and I will get the compressor myself. He understood, although of course he can't warranty whether things will work.
Two questions:
1) The shop measured some port on the compressor and said it measured 21mm. They said this comes in two sizes of port for this model year, and that mine did not measure what the 'book' said it would. I have not seen this mentioned where the compressors are sold. Any advice on getting this correct?
2) Will I need to buy another drier? It seems this one was run for about hour before the system was fully discharged. What about o-rings?
Thanks again for all the help,
Dave
So I need a new compressor, and rather than paying them $550 for a reman compressor at full retail, the shop discharged it and I will get the compressor myself. He understood, although of course he can't warranty whether things will work.
Two questions:
1) The shop measured some port on the compressor and said it measured 21mm. They said this comes in two sizes of port for this model year, and that mine did not measure what the 'book' said it would. I have not seen this mentioned where the compressors are sold. Any advice on getting this correct?
2) Will I need to buy another drier? It seems this one was run for about hour before the system was fully discharged. What about o-rings?
Thanks again for all the help,
Dave