Air Conditioning
02-17-2008, 07:24 AM
#1
Administrator
Thread Starter
Air Conditioning
Getting ready for our hot California winter, it's been getting into the upper 70's-80's here.
I just replaced the expansion valve and receiver on my truck,
How much oil and R-12 does it take?
Does the FSM have any pressure/temperature readings?
I am getting some interesting situations while charging it tonight besides the freezing bone chilling register temperatures.
Thanks.
Jim
I just replaced the expansion valve and receiver on my truck,
How much oil and R-12 does it take?
Does the FSM have any pressure/temperature readings?
I am getting some interesting situations while charging it tonight besides the freezing bone chilling register temperatures.
Thanks.
Jim
02-17-2008, 09:03 AM
#2
Adminstrator-ess
Total oil capacity is 7 oz, you only add that much if replacing the compressor.
If replacing: Evap. add 2 oz., Condenser or filter-drier add 1 oz.
The system takes 44 oz. of R-12.
Guess who finally bought a scanner.
If replacing: Evap. add 2 oz., Condenser or filter-drier add 1 oz.
The system takes 44 oz. of R-12.
Guess who finally bought a scanner.
02-17-2008, 10:45 AM
#3
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make sure you draw a good vacuum on system before you add any freon.
most of the time i will draw a vacuum a use it to draw the oil into the system
then draw vacuum again to 500 microns. then charge if it holds 500 microns.
if you are using oil in a pressurized can then add oil then let pressure out then
draw vacuum,or you can draw vacuum then add oil then charge. i like to draw a deep vacuum so i use oil thats not in a pressurized can
most of the time i will draw a vacuum a use it to draw the oil into the system
then draw vacuum again to 500 microns. then charge if it holds 500 microns.
if you are using oil in a pressurized can then add oil then let pressure out then
draw vacuum,or you can draw vacuum then add oil then charge. i like to draw a deep vacuum so i use oil thats not in a pressurized can
02-18-2008, 06:13 AM
#4
Administrator
Thread Starter
Ok guys what did I do wrong?
I finally got the time to repair a small leak that I had in my AC system, It was small and I was having a hard time finding it with my electronic detector so I built an injector and I injected some UV dye into the system but since the charge was low I disconnected the low pressure cutout and jumpered it so the compressor would circulate the dye so it could find the leak.
I found the leak was at the H-block, I did not even have to use my UV lamp to find it all it took was an inspection mirror and a good flashlight.
Last week I went to acquire the parts planning on having to replace the referigent lines if need be so I went to Dodge and got the part numbers and found I could get them local at another dealer. I also went to NAPA and they could also get me the parts cheaper except they would have to order it and it would take a few days.
This is the old H-block, it was leaking at the sealing surface.
So I found one at Auto Zone when I called at 5:05 P.M. then I ask him when you look at the end of it which side does the switch screw into it? He said on the left side. Ill be right there.
So I have my H-block in hand and get to the counter and he gets the part, he must not have known which of his hands was the left one because it was the other left hand. It was on the wrong side.
But checking the computer by application it shows the switch being on the right side facing it (drivers side)
#154773 was the one we found with the switch on the left side but it shows it is for 1986 and up? But by crossing the stamped number on my old one, one vendor showed it to be the same.
So this is the one that I brought home with me.
I transferred the switch over and then I reinstalled it back onto the evaporator followed by the lines.
I also installed a new accumulator (receiver / drier.)
After I got everything back together I connected up my manifold set and ran my vacuum pump to draw a vacuum. I ran it for about 15 minuets and closed the hand wheels and waited to see if there were any more leaks but after 15 minuets the needle had not moved (this was at night so I added a bit of extra time for the temperature) so I then reopened the hand wheels and continued to pump down the system. I know it should be longer but I ran it for an hour after the initial check.
Now here is where the weird stuff begins. I usually charge my system with about 47- 48 ounces of R-12 or whatever it takes to clear the sight glass..
So I put in the first can with the engine off and then I add the second one and it is probably half full so I start the engine it is probably 60* out tonight) and warm the can with my hands until I got it all in and then I went to add the third can but I looked into the sight glass and it was just clearing up with only an occasional bubble, you can see it is all liquid because of the UV dye that is circulating so now I am wondering if I had a lapse of consciousness or something and I counted 1,2 empty cans but yet it is showing full??
I went into the cab and expecting to feel warm air I was met with Cold brisk actually bone chilling frigid air. I went and got my Fluke I/R thermometer to have a check.. 18.6* Farenheit
OK what happened?
This is with the blower on High speed and the engine at about 1500 RPM.
So OK I think maybe there is a large bubble of something uncondensable or something and tomorrow when it is hot out the pressures will drop and I can install the last 2 cans but today I dove around all day with the A/C on high while freezing my behind off trying to figure out what had happened.
I ran the vacuum pump for 1 hour after it was at 29”; I have a Edwards HiVac industrial pump certified to 5 microns.
What happened?
I think maybe:
Malfunctioning expansion valve?
A burrito hidden inside the Accumulator?
Gauge readings:
The Low side is about 10 PSIG, (sign of a stuck expansion valve or low charge, But FREEZING air)
High Side? I broke my adapter and I will get a new one on Monday.
The outlet temperatures are normal for what my truck always has but I am stumped about why it works perfectly with only 24 ounces of R-12.
If it wasn’t for the fact of the cold air I would install the factory charge but the glass is already clear.
What do you think?
It is terrible to drive around Southern California in the winter time with a freezing A/C and with every breath blowing frost like a dragon.
I found the leak was at the H-block, I did not even have to use my UV lamp to find it all it took was an inspection mirror and a good flashlight.
Last week I went to acquire the parts planning on having to replace the referigent lines if need be so I went to Dodge and got the part numbers and found I could get them local at another dealer. I also went to NAPA and they could also get me the parts cheaper except they would have to order it and it would take a few days.
This is the old H-block, it was leaking at the sealing surface.
So I found one at Auto Zone when I called at 5:05 P.M. then I ask him when you look at the end of it which side does the switch screw into it? He said on the left side. Ill be right there.
So I have my H-block in hand and get to the counter and he gets the part, he must not have known which of his hands was the left one because it was the other left hand. It was on the wrong side.
But checking the computer by application it shows the switch being on the right side facing it (drivers side)
#154773 was the one we found with the switch on the left side but it shows it is for 1986 and up? But by crossing the stamped number on my old one, one vendor showed it to be the same.
So this is the one that I brought home with me.
I transferred the switch over and then I reinstalled it back onto the evaporator followed by the lines.
I also installed a new accumulator (receiver / drier.)
After I got everything back together I connected up my manifold set and ran my vacuum pump to draw a vacuum. I ran it for about 15 minuets and closed the hand wheels and waited to see if there were any more leaks but after 15 minuets the needle had not moved (this was at night so I added a bit of extra time for the temperature) so I then reopened the hand wheels and continued to pump down the system. I know it should be longer but I ran it for an hour after the initial check.
Now here is where the weird stuff begins. I usually charge my system with about 47- 48 ounces of R-12 or whatever it takes to clear the sight glass..
So I put in the first can with the engine off and then I add the second one and it is probably half full so I start the engine it is probably 60* out tonight) and warm the can with my hands until I got it all in and then I went to add the third can but I looked into the sight glass and it was just clearing up with only an occasional bubble, you can see it is all liquid because of the UV dye that is circulating so now I am wondering if I had a lapse of consciousness or something and I counted 1,2 empty cans but yet it is showing full??
I went into the cab and expecting to feel warm air I was met with Cold brisk actually bone chilling frigid air. I went and got my Fluke I/R thermometer to have a check.. 18.6* Farenheit
OK what happened?
This is with the blower on High speed and the engine at about 1500 RPM.
So OK I think maybe there is a large bubble of something uncondensable or something and tomorrow when it is hot out the pressures will drop and I can install the last 2 cans but today I dove around all day with the A/C on high while freezing my behind off trying to figure out what had happened.
I ran the vacuum pump for 1 hour after it was at 29”; I have a Edwards HiVac industrial pump certified to 5 microns.
What happened?
I think maybe:
Malfunctioning expansion valve?
A burrito hidden inside the Accumulator?
Gauge readings:
The Low side is about 10 PSIG, (sign of a stuck expansion valve or low charge, But FREEZING air)
High Side? I broke my adapter and I will get a new one on Monday.
The outlet temperatures are normal for what my truck always has but I am stumped about why it works perfectly with only 24 ounces of R-12.
If it wasn’t for the fact of the cold air I would install the factory charge but the glass is already clear.
What do you think?
It is terrible to drive around Southern California in the winter time with a freezing A/C and with every breath blowing frost like a dragon.
02-18-2008, 06:19 AM
#5
Administrator
Thread Starter
Thank you Dave for the T/P chart, exactly what I needed.
Thanks Jim
Thanks Jim
02-20-2008, 07:53 AM
#7
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Jim, in you first pic, below, I notist that you temp probe is missing from the tube?????????
Did you put it back in to the pipe...........Just below were you hooked up you AC charge line.
How far the probe is installed or pulled out will deside when the compressor will shut off, or how cold the ac gets.
If that don't work i would us the new gaskets and the old H block.
It's probaly building some pretty high pressures on the high side of the system........Good thing is's now a 100* out side
Did you put it back in to the pipe...........Just below were you hooked up you AC charge line.
How far the probe is installed or pulled out will deside when the compressor will shut off, or how cold the ac gets.
If that don't work i would us the new gaskets and the old H block.
It's probaly building some pretty high pressures on the high side of the system........Good thing is's now a 100* out side
I finally got the time to repair a small leak that I had in my AC system, It was small and I was having a hard time finding it with my electronic detector so I built an injector and I injected some UV dye into the system but since the charge was low I disconnected the low pressure cutout and jumpered it so the compressor would circulate the dye so it could find the leak.
I found the leak was at the H-block, I did not even have to use my UV lamp to find it all it took was an inspection mirror and a good flashlight.
Last week I went to acquire the parts planning on having to replace the referigent lines if need be so I went to Dodge and got the part numbers and found I could get them local at another dealer. I also went to NAPA and they could also get me the parts cheaper except they would have to order it and it would take a few days.
This is the old H-block, it was leaking at the sealing surface.
So I found one at Auto Zone when I called at 5:05 P.M. then I ask him when you look at the end of it which side does the switch screw into it? He said on the left side. Ill be right there.
So I have my H-block in hand and get to the counter and he gets the part, he must not have known which of his hands was the left one because it was the other left hand. It was on the wrong side.
But checking the computer by application it shows the switch being on the right side facing it (drivers side)
#154773 was the one we found with the switch on the left side but it shows it is for 1986 and up? But by crossing the stamped number on my old one, one vendor showed it to be the same.
So this is the one that I brought home with me.
I transferred the switch over and then I reinstalled it back onto the evaporator followed by the lines.
I also installed a new accumulator (receiver / drier.)
After I got everything back together I connected up my manifold set and ran my vacuum pump to draw a vacuum. I ran it for about 15 minuets and closed the hand wheels and waited to see if there were any more leaks but after 15 minuets the needle had not moved (this was at night so I added a bit of extra time for the temperature) so I then reopened the hand wheels and continued to pump down the system. I know it should be longer but I ran it for an hour after the initial check.
Now here is where the weird stuff begins. I usually charge my system with about 47- 48 ounces of R-12 or whatever it takes to clear the sight glass..
So I put in the first can with the engine off and then I add the second one and it is probably half full so I start the engine it is probably 60* out tonight) and warm the can with my hands until I got it all in and then I went to add the third can but I looked into the sight glass and it was just clearing up with only an occasional bubble, you can see it is all liquid because of the UV dye that is circulating so now I am wondering if I had a lapse of consciousness or something and I counted 1,2 empty cans but yet it is showing full??
I went into the cab and expecting to feel warm air I was met with Cold brisk actually bone chilling frigid air. I went and got my Fluke I/R thermometer to have a check.. 18.6* Farenheit
OK what happened?
This is with the blower on High speed and the engine at about 1500 RPM.
So OK I think maybe there is a large bubble of something uncondensable or something and tomorrow when it is hot out the pressures will drop and I can install the last 2 cans but today I dove around all day with the A/C on high while freezing my behind off trying to figure out what had happened.
I ran the vacuum pump for 1 hour after it was at 29”; I have a Edwards HiVac industrial pump certified to 5 microns.
What happened?
I think maybe:
Malfunctioning expansion valve?
A burrito hidden inside the Accumulator?
Gauge readings:
The Low side is about 10 PSIG, (sign of a stuck expansion valve or low charge, But FREEZING air)
High Side? I broke my adapter and I will get a new one on Monday.
The outlet temperatures are normal for what my truck always has but I am stumped about why it works perfectly with only 24 ounces of R-12.
If it wasn’t for the fact of the cold air I would install the factory charge but the glass is already clear.
What do you think?
It is terrible to drive around Southern California in the winter time with a freezing A/C and with every breath blowing frost like a dragon.
I found the leak was at the H-block, I did not even have to use my UV lamp to find it all it took was an inspection mirror and a good flashlight.
Last week I went to acquire the parts planning on having to replace the referigent lines if need be so I went to Dodge and got the part numbers and found I could get them local at another dealer. I also went to NAPA and they could also get me the parts cheaper except they would have to order it and it would take a few days.
This is the old H-block, it was leaking at the sealing surface.
So I found one at Auto Zone when I called at 5:05 P.M. then I ask him when you look at the end of it which side does the switch screw into it? He said on the left side. Ill be right there.
So I have my H-block in hand and get to the counter and he gets the part, he must not have known which of his hands was the left one because it was the other left hand. It was on the wrong side.
But checking the computer by application it shows the switch being on the right side facing it (drivers side)
#154773 was the one we found with the switch on the left side but it shows it is for 1986 and up? But by crossing the stamped number on my old one, one vendor showed it to be the same.
So this is the one that I brought home with me.
I transferred the switch over and then I reinstalled it back onto the evaporator followed by the lines.
I also installed a new accumulator (receiver / drier.)
After I got everything back together I connected up my manifold set and ran my vacuum pump to draw a vacuum. I ran it for about 15 minuets and closed the hand wheels and waited to see if there were any more leaks but after 15 minuets the needle had not moved (this was at night so I added a bit of extra time for the temperature) so I then reopened the hand wheels and continued to pump down the system. I know it should be longer but I ran it for an hour after the initial check.
Now here is where the weird stuff begins. I usually charge my system with about 47- 48 ounces of R-12 or whatever it takes to clear the sight glass..
So I put in the first can with the engine off and then I add the second one and it is probably half full so I start the engine it is probably 60* out tonight) and warm the can with my hands until I got it all in and then I went to add the third can but I looked into the sight glass and it was just clearing up with only an occasional bubble, you can see it is all liquid because of the UV dye that is circulating so now I am wondering if I had a lapse of consciousness or something and I counted 1,2 empty cans but yet it is showing full??
I went into the cab and expecting to feel warm air I was met with Cold brisk actually bone chilling frigid air. I went and got my Fluke I/R thermometer to have a check.. 18.6* Farenheit
OK what happened?
This is with the blower on High speed and the engine at about 1500 RPM.
So OK I think maybe there is a large bubble of something uncondensable or something and tomorrow when it is hot out the pressures will drop and I can install the last 2 cans but today I dove around all day with the A/C on high while freezing my behind off trying to figure out what had happened.
I ran the vacuum pump for 1 hour after it was at 29”; I have a Edwards HiVac industrial pump certified to 5 microns.
What happened?
I think maybe:
Malfunctioning expansion valve?
A burrito hidden inside the Accumulator?
Gauge readings:
The Low side is about 10 PSIG, (sign of a stuck expansion valve or low charge, But FREEZING air)
High Side? I broke my adapter and I will get a new one on Monday.
The outlet temperatures are normal for what my truck always has but I am stumped about why it works perfectly with only 24 ounces of R-12.
If it wasn’t for the fact of the cold air I would install the factory charge but the glass is already clear.
What do you think?
It is terrible to drive around Southern California in the winter time with a freezing A/C and with every breath blowing frost like a dragon.
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02-20-2008, 08:01 AM
#8
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i used one of them h-blocks with pressure tap on wrong side and i had trouble
with it too. i thought it just had the tap on wrong side but the metering was not the same. i got weird low side readings. i bought new seals and put the old one back on and pressures was right. good luck
with it too. i thought it just had the tap on wrong side but the metering was not the same. i got weird low side readings. i bought new seals and put the old one back on and pressures was right. good luck
02-21-2008, 03:36 AM
#9
Administrator
Thread Starter
Jim, in you first pic, below, I notist that you temp probe is missing from the tube?????????
Did you put it back in to the pipe...........Just below were you hooked up you AC charge line.
How far the probe is installed or pulled out will deside when the compressor will shut off, or how cold the ac gets.
If that don't work i would us the new gaskets and the old H block.
It's probaly building some pretty high pressures on the high side of the system........Good thing is's now a 100* out side
Did you put it back in to the pipe...........Just below were you hooked up you AC charge line.
How far the probe is installed or pulled out will deside when the compressor will shut off, or how cold the ac gets.
If that don't work i would us the new gaskets and the old H block.
It's probaly building some pretty high pressures on the high side of the system........Good thing is's now a 100* out side
I have removed the probe and the cycling switch a few years ago when I installed a relay to control the compressor.
I have never had any problems with the evaporator icing up and I usually get register temps in the 20*'s on Med and around 30* on High.
The leak I was having was from the H-block; there were some small pits in the sealing surface. I probably could have taken them out with some 1500 grit wet/dry on a block of glass but it was cheap enough to replace it.
I did find another one of my High Side adapter so I am going to check it today and see what I am getting on the High Side.
It is still odd that I was able to fill the system with only 24 ounces of R-12.
Even with the AC off and enough time to equalize I will watch the sight glass and engage the compressor and the liquid in the sight glass will not surge signifintly as if it was undercharged, also there is no unusual noises from the compressor.
My only immediate concern would be from lack of compressor lubrication but the liquid side is full so the oil is there.
I was cruising down the freeway tonight and thought I would see if it was still as cold as it was the other day, no such luck, It has gotten colder.
This was with the blower on the second notch from High, at 70 MPH.
I think I have turned my truck into a deep freeze; this is actually a bit uncomfortable when it freezes the steering wheel.
I will know more today when I get the gauges back on it and get some readings.
Thanks Jim
02-21-2008, 05:17 AM
#10
DTR's Night Watchman & Poet Laureate
ya know Jim, theres something ironic( and intrisicly wrong) about a thread about your A/C being too cold while most of us are dealing with heaters not being hot enough......
02-22-2008, 05:07 AM
#11
Administrator
Thread Starter
That is kind f funny, actually my heater does not get real hot either I do not know how many BTU my heater core is supposed to be but on my next occasion to remove it I will get the good one from Napa.
My temperature gauge always runs about in the center of the scale.
I guess that will be my next venture to make my heater blow out hotter air, in theory I guess I should be able to get the air as hot as the water is circulating through the core.
I found my other High Side adapter and I was able to get a pressure reading, although it was on the cool side today and got up to about 70* with the AC on high I was getting only 120 PSI on the High side and 10 PSI on the Low side while the register air was at 20* F. of course the ambient air temperature and ram air through the radiator have a big influence on the output temperature.
Later on today I went to a local Air Conditioning shop where I get a lot of my parts and I talked to the owner about what had happened and has came up with the same answer that if I only put in ½ of the charge than it should only be starting to get cold but when he felt the air from the vents he stood shaking his head and said how did you do that?
It is still a bit low on charge because I will get streaks in the sight glass so I will probably add a few more ounces to clear it up.
Just to reassure myself I ask him if there was any way I could do any damage to my compressor by running it low but he said that as long as the oil charge is up to specs. And the liquid line is full it would be ok, He can’t explain why it is working but he said as long as it is cold to leave it.
He saw that there was no cycling switch and I explained how I removed it and controlled it with a relay, the only addition I might make to this modification is I might add a Low Pressure cutout on the Low Side Schrader valve to cut out the compressor if it goes into a suction because by then I should be blowing ice chips from the vents.
He checked the part number of the H-Block that I installed and he said it covered from 1986 to 1993 and the metering did not change much over the years.
I guess in the summer time I could start selling Ice Cream and Popsicles from my truck to make extra money.
Jim
02-22-2008, 07:07 AM
#12
1st Generation Admin
While I have not had the need to go deep into my heap's AC (still running R12) and have the experience working with it, I have a nagging suspicion that new H-block is stuck open.
Jim, the next chance you get, with the indoor air blower set to high, and the AC system stabilized with five or ten minutes of run time. Temperature control set to it's coldest, Engine at about 1200 or so RPM's,,. . .
Note the head pressure (and ODA temp), suction pressure (and IDA temp) and the temperature of the suction line as it leaves the evaporator on it's way back to the compressor. There's need to determine if you're in fact flooding back to the compressor.
Jim, the next chance you get, with the indoor air blower set to high, and the AC system stabilized with five or ten minutes of run time. Temperature control set to it's coldest, Engine at about 1200 or so RPM's,,. . .
Note the head pressure (and ODA temp), suction pressure (and IDA temp) and the temperature of the suction line as it leaves the evaporator on it's way back to the compressor. There's need to determine if you're in fact flooding back to the compressor.
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