Dude....you were better off before you touched it....the low side Psi is roughly equal to the center vent temp....the low side pressures should be in the upper 30s.
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R134a Capacity
- Thread starter Cincinnati Scott
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Dude....you were better off before you touched it....the low side Psi is roughly equal to the center vent temp....the low side pressures should be in the upper 30s.
There should be no bubbles.:smile:
When Hondas come off the truck from the factory they have some bubbles in the sight glass.
And furthermore when I asked the instructors at the Acura Training facility in Torrance why there were bubbles in the sight glass? They said because inorder for the system to work properly there had to be some allowance for heat expansion and contraction.
I don't make this S#*t up it's just what American Honda told me.
Thanks for the input guys.
I'll lower my pressure a bit.
I'll lower my pressure a bit.
Ya know thats some good stuff to know.:wink: Over the years I've been taught the site should be clear. Damn I've been wasting good freon. Thank's.
It seems my NSX's AC is a little anemic in dealing with 95 F 85 % humidity. So I did a search, saw this thread, and decided to check and if needed add freon to my system.
Note that both condenser fans are running, the inside fan changes speed, cool air comes out of all vents, etc, and the condensate drain under the driver side is flowing freely.
At approx 80F ambient today, the low side pressure was 45 PSI, which is right on the Acura spec as well as the spec that came with the Interdynamics kit. (I was amazed, since the system was last evacuated and charged in 2001) Note that I could clearly see bubbles in the sight glass, which seems to agree with the reported comment from Acura Training in Torrence.
As to port locations, on a '96 the low side port is on the firewall about 4" above the positive terminal of the battery. The high side port is behind the left (driver's) side headlight. The R134a connectors are different size, so its virtually impossible to connect to the wrong port.
My dissappointment is the NSX AC just doesn't keep up with this heat wave we had this past week. Was I doing something wrong??
So, I decided I would also check the AC on my clunker family sedan. Well, the first thing I found was the compressor was cycling because the pressure dropped too low. (This car's AC hasn't been checked or charged since approximately 1998 or 1999.) I began to add freon, and as the pressure came up to 25 PSI, the cycling stopped. I charged it to 40 PSI and quit. I now have another place to store ice cream.:biggrin:
I suppose when my NSX system was evacuated and charged in 2001, its possible they didn't get all the air and/or moisture out. But other work that place did for me was excellent..... So, either the NSX system is a little anemic at these high temps (which are still 20F cooler than a good summer day in Phoenix), or I should do a complete evacuation and recharge.
Comments?
Note that both condenser fans are running, the inside fan changes speed, cool air comes out of all vents, etc, and the condensate drain under the driver side is flowing freely.
At approx 80F ambient today, the low side pressure was 45 PSI, which is right on the Acura spec as well as the spec that came with the Interdynamics kit. (I was amazed, since the system was last evacuated and charged in 2001) Note that I could clearly see bubbles in the sight glass, which seems to agree with the reported comment from Acura Training in Torrence.
As to port locations, on a '96 the low side port is on the firewall about 4" above the positive terminal of the battery. The high side port is behind the left (driver's) side headlight. The R134a connectors are different size, so its virtually impossible to connect to the wrong port.
My dissappointment is the NSX AC just doesn't keep up with this heat wave we had this past week. Was I doing something wrong??
So, I decided I would also check the AC on my clunker family sedan. Well, the first thing I found was the compressor was cycling because the pressure dropped too low. (This car's AC hasn't been checked or charged since approximately 1998 or 1999.) I began to add freon, and as the pressure came up to 25 PSI, the cycling stopped. I charged it to 40 PSI and quit. I now have another place to store ice cream.:biggrin:
I suppose when my NSX system was evacuated and charged in 2001, its possible they didn't get all the air and/or moisture out. But other work that place did for me was excellent..... So, either the NSX system is a little anemic at these high temps (which are still 20F cooler than a good summer day in Phoenix), or I should do a complete evacuation and recharge.
Comments?
I punch 1.4lbs into the control panel on my A/C Machine then press "charge", works everytime
Zahntech is right.
If you have converted your R12 system to 134a 1.4lbs is the correct amount to put in the NSX system
I use metric so it's .65kg.
A few more things to check.
1) The adjustment and functioning of the water valve and cable.
2) Do a Climate control diagnostic self check.
3) Take out the console plate and make sure the ambient temp. sensor fan, the one behind the little grill by the emergency brake, is not clogged with lint keeping the sensor from reading the air temp properly.
4)Make sure the condensers are not covered with leaves or other debris and air can pass through freely.
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Joe, are you sure? I thought it was 0.85 kg or 10% less than R12 (0.95 kg).
The system looses freon over time, this can't be eliminated. The system should also be evacuated from time to time to add up the lost freon and to get the moisture out. A fully working A/C system in the NSX is said to be superior.
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Thanks for the suggestions. I'll check the water valve and cable. I'll also check the external temperature sensor.
I already did the CCU self test (OK), did a preventative cleaning/check of the console fan this spring, and verified no items or critters blocking the condensers.
'95 & '96 came with R134a, so there was no conversion involved. (As an FYI, the '95 manual lists capacity as 28 to 30 oz. The 1.4 lbs suggested by Zahntech for a system converted from R12 is about 6 oz less. So besides the other component differences, apparently capacity was slightly less.)
If all else fails, I'll resort to the evacuate and refill. The manual says replace any oil evacuated with the freon. Has anyone discovered it better to add a little extra oil? If so, how much -- just round up to the next ounce, for example?
I already did the CCU self test (OK), did a preventative cleaning/check of the console fan this spring, and verified no items or critters blocking the condensers.
'95 & '96 came with R134a, so there was no conversion involved. (As an FYI, the '95 manual lists capacity as 28 to 30 oz. The 1.4 lbs suggested by Zahntech for a system converted from R12 is about 6 oz less. So besides the other component differences, apparently capacity was slightly less.)
If all else fails, I'll resort to the evacuate and refill. The manual says replace any oil evacuated with the freon. Has anyone discovered it better to add a little extra oil? If so, how much -- just round up to the next ounce, for example?
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According to the manual which says capacity is 900-950 grams. per the instruction on the Honda retro fit kit it should be 50grams less than the r12 capacity so, it would be .85 to .90kg. You are right. Good catch.
I got the number I mentioned after doing a calculation from the label on the car after a recent conversion. I'll double check that tomorrow. I must of goofed or the info on the car is different than the manual. I'll get back to you on it.
update: My powers of recollection aren't so hot. I recently used 1.65 lbs (that's where the .65 came from)which makes more sense. Again, nice catch Thomas.
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I own a 96 as well. .80 to .85g is what my sticker on the rad support says( 28.2 to 30oz)
External temp sensor checked out OK.
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The water valve appears to work smoothly. But, the cable did not have it fully closed (maybe 5 or 10 degrees open). I positioned the valve fully closed then re-adjusted the cable. Tomorrow should hit 90 F again & I plan to head to the beach. I'll see how it does.
Thanks again for this tip, pbassjo; its not in the checklist in the manual
. The water valve appears to work smoothly. But, the cable did not have it fully closed (maybe 5 or 10 degrees open). I positioned the valve fully closed then re-adjusted the cable. Tomorrow should hit 90 F again & I plan to head to the beach. I'll see how it does.
Re: Ra Capacity
It could make a big difference. It doesn't take much heat to overcome the cold air blowing in.
It's like having the windows open a inch when it's 90 degrees out with the ac on. The heat is going to win.
I give credit to Mark Basch through LarryB at NSXPO2004 for that tip.
BTW, do you have shields in front of your a/c condensers like the one offered by Dali?
It could make a big difference. It doesn't take much heat to overcome the cold air blowing in.
It's like having the windows open a inch when it's 90 degrees out with the ac on. The heat is going to win.
I give credit to Mark Basch through LarryB at NSXPO2004 for that tip.
BTW, do you have shields in front of your a/c condensers like the one offered by Dali?
It almost hit 90F today, with high humidity. AC performed noticeably better. Thanks again for the tip, and ultimately, thanks to Mark via Larry.
I do not have shields in front of the condensers - its pure stock front-end body-work, including the OEM license plate holder.
I do not have shields in front of the condensers - its pure stock front-end body-work, including the OEM license plate holder.
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If you charge till all the bubbles are gone AT IDLE, you are considerabally overcharged. Thats why new cars used to show bubbles at idle, when they had a sight glass. If you're going to take the riisk of charging by sight glass, make sure and do it around 2200 rpm. If you want to charge it correctly regardless of which gas you use / switched to- use guages and charge to 27/or 28 low side and 170 or 175 high side at about 1500 rpm.
Mark
Mark
