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AC recharge 91 nsx help. R-134A

Joined
20 May 2014
Messages
240
Location
Massachusetts
So summers pretty much here in the Boston area. My ac is working but when it hits 90 degrees plus it's not enough & I believe I'm running low. Can I just add r-134a?
 
So summers pretty much here in the Boston area. My ac is working but when it hits 90 degrees plus it's not enough & I believe I'm running low. Can I just add r-134a?
No you cannot add R134 to a R12 system. It will damage your compressor. Look on the filter drier located between the bumper and the radiator. If it is bubbling, your low. You may also want to make sure that both of you condenser fans are working by putting your hand in the front fenders and checking for airflow.
If the car has already had a retrofit to R134 then add as needed.
 
How would I be able to add the r12 ?
I'm an hvac technician by trade, you either use R12 which is very hard to find or use R414b which is a direct drop in refrigerant. Both of these require epa certification to buy it. Or you could have Acura convert it to R134. But I prefer R414 over R134. You keep the same oil, same pressures, everything is matched.
If you know any guys who do hvac you can get R414 but they only sell it by 30 pound jugs or more. It is pricey too.
Is your site glass bubbling while in operation?

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Here's a link of why it is a great reason over R134a. Only reason why manufacturers do not use it is for epa and environment type reasons. You could probably find small cans of it on eBay.
http://www.refrigerants.com/hcfc-r414b.htm

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By direct drop, that means you can mix it with R12. No recovery needed, no oil change, just top it off.
 
I'm an hvac technician by trade, you either use R12 which is very hard to find or use R414b which is a direct drop in refrigerant. Both of these require epa certification to buy it. Or you could have Acura convert it to R134. But I prefer R414 over R134. You keep the same oil, same pressures, everything is matched.
If you know any guys who do hvac you can get R414 but they only sell it by 30 pound jugs or more. It is pricey too.
Is your site glass bubbling while in operation?

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Here's a link of why it is a great reason over R134a. Only reason why manufacturers do not use it is for epa and environment type reasons. You could probably find small cans of it on eBay.
http://www.refrigerants.com/hcfc-r414b.htm

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By direct drop, that means you can mix it with R12. No recovery needed, no oil change, just top it off.

Thanks but if the r414 is pricey, I'm all set then. To convert my r12 to r134a .. What's that cost usually at the dealer? & also, I don't even know if my ac was converted to r134a. Also how would I know that? Thanks
 
I'm not sure of the cost of the conversion nowadays. I just did an eBay search and it appears they sell small cans of it there. I'm just not 100% sure if they will allow you to buy it being non epa certified. Here is the problem with a R134 conversion. Your condenser fan motors make a certain amount of cfm which are matched for R12 specification. Also, your (txv) thermostatic expansion valve is also geared towards an R12 system. This is why many complain of ac not being cold while sitting stopped in traffic. But then again, some people never notice it. Just my recommendation.

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If someone converted it and converted it correctly, there will be a tag underneath of your hood saying so. Unfortunately, there is nothing to stop people from going to autozone, buying R134 and topping it off. So unless your car came with very detailed service history, there really isn't a way of absolutely knowing for sure.
 
Do not mix R134A with R12. If you do the conversion, I'd recommend changing your o-rings throughout the system. I still run R12 in mine and it blows ice cold. I never did the conversion since R12 cools better than R134a.
 
A/c

The guy from Ca. is not giving you complete information. Don't let him scare you off from this simple job.
The Ca. world is far different than the real world.

Do a little searching and refer to the factory manual and you'll see that it isn't so hard to change your system to R-134 and / or have a dealer do an a/c system health check and they can either find any leak with dye and fix it or do the conversion, or, it's not so hard to DIY after they recover the remaining freon from your car before you carry on.

Kaz has done a recent update about compressors for the NSX that explains the compressor model numbers and their applications that is the usual, outstanding information for the DIYer, in the real world.

Cheers
nigel
 
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Also, the heater valve cable for the water control can go out of adjustment over the years. If it does, the ac is fighting the heater, and the heater wins. Joe L of Vince's auto body told me about this years ago, and it made a tremendous difference on my '96.
In the '95 service manual, the adjustment is on page 22-56, step 4.

The cable adjustment spot is located on the drivers side, on the firewall, under the hood. The whole adjustment procedure might take 30 seconds. Sorry, but I posted something on this on prime years ago, possibly with a picture, but at the moment don't have time to locate it.
 
lol, scare him off. That's funny. Yes it is easy to do conversions if you simply break laws and purge your R12 into the air like a normal hack would. Recovery and correct charging is done via a recovery machine and a vacuum pump. Something a diy person does not have. But yeah, don't listen to me. I'm dumb.
 
Jinks;
Open your mouth before you read the post !
It says, "have a dealer recover the remaining freon" so it does show you aren't really as sharp as you might think.
And yes, your reply does tend to make an unknowing DIYer think it's something to be scared of when it is really one of the simple, basic DIYs.

Black NSX F1;
Just be sure to not let the High side pressure, exceed 185 lbs when you do your charge. If you do you can risk the chance of blowing the over pressure valve, if it has one, or blowing the seal.
Do refer to Kazs' latest thread for the part number of the current p/n of the compressor you might want to use if yours is worn.

Other than that it's a simple DIY.

Cheers
nigel
 
Once the system is assembled, don't you have to pull a vacuum to remove the air before charging?
Yes, it appears the other posted did, not open his "mouth" and read my post.:rolleyes:
FYI, I have been epa certified and worked with refrigerant since 1997 but what the hell do I know.

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Jinks;
Open your mouth before you read the post !
It says, "have a dealer recover the remaining freon" so it does show you aren't really as sharp as you might think.
And yes, your reply does tend to make an unknowing DIYer think it's something to be scared of when it is really one of the simple, basic DIYs.

Black NSX F1;
Just be sure to not let the High side pressure, exceed 185 lbs when you do your charge. If you do you can risk the chance of blowing the over pressure valve, if it has one, or blowing the seal.
Do refer to Kazs' latest thread for the part number of the current p/n of the compressor you might want to use if yours is worn.

Other than that it's a simple DIY.

Cheers
nigel

Recover AND vacuum. The original posted was asking for recommendations. So I gave them.

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If people here wish to keep the same old R12 mineral oil for their new R134 system, that is fine by me. I just do not recommend it. Also, you will need to undercharge your R134 system as it is a higher capacity over R12.
Removal of air is needed but vacuuming a system is mostly for moisture removal. Moisture in the system causes oils to become highly acidic therefore breaking down the compressor and shortening its life.
R12 systems run mineral oil while R134 runs either ester based or poly based oils.
 
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I'm done playing your silly little game of arguing points.
The fellow wanted some simple advice and not step by step instructions and you seem to want to argue more than help.
By the by, i've been EPA licensed and certified, (so important to you, more than competent help) for decades and been doing helicopters and mulit-eng aircraft a/c systems for the same time which are the same systems as autos in nearly all cases.
And, when freon leaks, the exchange of freon for air creates hydro-chloric acid and corrodes the system from the inside thus shortening the system life as most a/c system tubing / filter driers are aluminum.

Per the maintenance manual, Honda recommends doing a vacuum for 15 min. and then do a leak check to be sure all the air has been removed and no leaks. After the system has been broken open, run the vacuum for 45 minutes to be sure.
Do replace the filter drier before doing the 134 change, (Honda dealers sell a conversion kit).

Cheers
nigel
 
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I'm not EPA certified or anything like that but here's what I did.

My original R12 system stopped working.
So I took the NSX to the dealer and had my R12 system purged to remove any R12 remaining.
Then I bought and installed the Honda OEM r134a retrofit kit.
Then I had the dealer test the system for leaks.
No leaks were found.
Then the R134a from the retrofit kit was added following the Honda instructions.
My A/C works fine now.
 
A/c

There you go JD, it's just that simple.

The only thing I did different is because the 134 system uses higher pressure and the o-rings are easy to get to, I changed my o-rings to the new, green ones just to be sure as mine are original from 1992, and a new filter / drier while the system was empty.

Cheers
nigel
 
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I got a can of r12 on eBay along with a recharge adapter, gage, etc. Which port do in the hood do I put the groin into?

I just got my AC control unit fixed through ScienceofSpeed and their exchange program.

Thanks,

Ken

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Damn you auto correct!! I meant which port in the hood do I put the freon into! LOL!
 
There you go JD, it's just that simple.

The only thing I did different is because the 134 system uses higher pressure and the o-rings are easy to get to, I changed my o-rings to the new, green ones just to be sure as mine are original from 1992, and a new filter / drier while the system was empty.

Cheers
nigel

The Honda retrofit kit came with the new higher pressure O-rings and I forgot that I too replaced the dryer while I was at it.
 
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I got a can of r12 on eBay along with a recharge adapter, gage, etc. Which port do in the hood do I put the groin into?

I just got my AC control unit fixed through ScienceofSpeed and their exchange program.

Thanks,

Ken

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Damn you auto correct!! I meant which port in the hood do I put the freon into! LOL!

The larger port to the right side of the battery.

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I'm done playing your silly little game of arguing points.
The fellow wanted some simple advice and not step by step instructions and you seem to want to argue more than help.
By the by, i've been EPA licensed and certified, (so important to you, more than competent help) for decades and been doing helicopters and mulit-eng aircraft a/c systems for the same time which are the same systems as autos in nearly all cases.
And, when freon leaks, the exchange of freon for air creates hydro-chloric acid and corrodes the system from the inside thus shortening the system life as most a/c system tubing / filter driers are aluminum.

Per the maintenance manual, Honda recommends doing a vacuum for 15 min. and then do a leak check to be sure all the air has been removed and no leaks. After the system has been broken open, run the vacuum for 45 minutes to be sure.
Do replace the filter drier before doing the 134 change, (Honda dealers sell a conversion kit).

Cheers
nigel
Your posts really advises me of your age demographic here. Have a great day.

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If you actually READ my first post. I did not give him step by step instructions. I told him do not mix refrigerants. Use R12, R414 OR,,,,,,,,, wait for it! Read it !!!! Do the conversion. Punk....

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All the B.S. I caught on this thread for sharing a direct drop in refrigerant replacement which is readily available over R12 was apparently trumped by ignorance and biased opinions for people who study the service manual and just want to tell me that I do not live in the "real" world. That's pretty harsh. Forgive me for sharing.... I think I will take a break from this all now.
 
Well then, all this came to a good ending besides helping some fellow NSXers out with their A/C questions.

Cheers
nigel
 
I have some extra cans in storage that I'd be willing to let go. PM me if you need some.
 
Well then, all this came to a good ending besides helping some fellow NSXers out with their A/C questions.

Cheers
nigel
Actually Nigel, I think viewers here got a good perspective from both sides of the spectrum via my post and your own. Let's be friends now and put B.S. aside.
Thank you,
AJ.
 
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