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How can I determine if the compressor is bad?
As a previous poster said, you made a couple of errors. You never add Freon to the high side. If you are new at this you should always only add gas not liquid.
If charged it wrong it could be frozen in some small openings.
You should start all over, vacuum and charge.
When you charge, engine rpm 2000 to 2500. Bucket of hot water to put the can in so the valve opening does not freeze. You may have to make the water warm again before you finish.
You might need a external fan in front of the radiator to help the system take the Freon.
Or , if you have more money than time spend the $150 and have someone else tell you your compressor is bad. If it is cooling some it probably is ok. IMHO
 

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You cannot charge a system simply based on pressures.
Correct.

Not sure what you are saying.
I think the crux of WiiMaster's post is that to even enter the P/T charts in the Honda service manual, you need to run the system to equilibrium at the manual's specified engine RPM, and measure both the stabilized inlet and outlet temperatures, and have an accurate value of the relative humidity (which it appears you did). I use two channels on my datalogger for the temperatures.

Even then, the gauge values arrived at by running the chart are more for troubleshooting, and cannot be used to assess charge state.

Is it possible that your gauge set is not working correctly? It seems weird, those pressures. They're backwards.

I'm in agreement with geotek's post on the situation, and rbhollobaugh. Start over.

One item that I do whenever I recharge (by myself or using a professional shop) is to replace the Schrader valves. I have a toolkit by MasterCool that allows me to do that without losing refrigerant.

OF

Edited for clarity
 

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Thanks for the reply.
The compressor did not run when I started the car, I stopped the car, jumped the relay and restarted the car and the compressor ran sucking in about 10 more oz of refrigerant.
The compressor was still running when I quit, but I still can't get the rest of the refrigerant in.
What is curious to me is if the system is low or empty as the shop guy said, you should be able to detect along the ac lines signs where it leaked out. Look for oily residue. Common areas are the low and high ports, low and high flexible hose connecting to and from the compressor. (I just replaced both of these hoses on my other car- very oily at compressors end). And if you actually find it, how can the system hold its vacuum if there is a leak? On the flip side, if you were able to hold the vacuum, where did all the refrigerant go if there is no leak in the system to begin with? Does not seem to add up.

Anyway, if I were you, I would start over, as I and a few others have already mentioned, by vacuum pumping the system again. You will however need to release the refrigerant you put in there. Remove the jump you put in for the compressor clutch. And only add refrigerant on the low side when the car and ac is running. Once enough refrigerant is in the system, the clutch will engage and the system will cycle on and off. This cycling will help in sucking more of the refrigerant you are trying to put it. Put a meat thermometer in your front vent so you see how cold it can get.

Or you can just remove the compressor clutch jump. Try recharging only on the low side while engine and ac is running. Shake the can or turn it upside-down or raise it up while upside down. See how the system reacts without your jump intervention.

Lastly, take it to the shop and let them do everything. Good luck.
 

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where did all the refrigerant go if there is no leak in the system to begin with? Does not seem to add up.
Normal for the system to lose some refrigerant over a period of several years. You could lose half your refrigerant in around 7 years.
 
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Normal for the system to lose some refrigerant over a period of several years. You could lose half your refrigerant in around 7 years.
Sure, O rings/seals degrade over time, so what should be a closed system, is not so closed anymore. Sounds like a leak to me.

Anyways, in OP case, seems like its more of a sudden hot air coming out than a slow leak of 7 years. Point here is to look for signs of oily residue along the lines.
 

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Sure, O rings/seals degrade over time, so what should be a closed system, is not so closed anymore. Sounds like a leak to me.
You can change every O ring and seal if you want. But the truth is you're still going to lose some over time.
 
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I've heard, anecdotally, that on average a properly assembled automotive A/C system will lose about 1 ounce of refrigerant per year. They can lose more.

OF
 

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You can change every O ring and seal if you want. But the truth is you're still going to lose some over time.

Yes, that is what people do when you have a leak. I also believe that the heat in the engine bay helps degrading the rubber seals and O rings. Starts leaking out at a very small amount. Almost unnoticeable. Its the life cycle of seals. Hence, you either change them out or keep recharging your ac until that leak becomes bigger and eventually your part no longer function properly. No matter how small the leak is, its still a leak if it escapes a closed system. That is the beauty of being able to fix the problem by having available tools, parts and supplies accessible to regular folks like you and me. No need to go to the shop to keep your AC cold. Which we all want.
 

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Just a note about charging on the high side. It is dangerous (very high pressure can blow the can you are charging from) and ineffective (as the pressure will generally be above the pressure in the can you are charging from). It is not gonna' break your MVAC system, and you most certainly can not wind up with refrigerant in the "wrong place" so as to call for removing and recharging just to get in in the right port.

A good indicator of a failed compressor is (virtually) equal pressures when engaged.
 
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There are no apparent leaks, the system holds a vacuum, everything looks ok.
Any help will be greatly appreciated.
Thank you
Any progress with your situation?

Here's a question: how warm was the outside air temperature when you did all this? You're in Florida, so if the van sat overnight, and the OAT was no less than 80°F, the ambient system pressure (compressor not running, assuming refrigerant at same temp as OAT) would be between 85 and 90 psi.

This is assuming you started at daybreak so as not to get too sweaty while on this job.

That's why I asked about the gauges. Those numbers just were not what I would expect, running or not.

OF
 

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What he ^^^ said. The T/P chart for R-134a will show a P value close to the T value in the likely ambient T range, say 60 to 100 F.
 

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...and the newer refrigerants operate at higher pressures on both sides of the compressor.

It's also a materials science challenge to find compounds that seal properly with newer refrigerants. R-134a can actually dissolve into O-ring material a bit more readily than R-12 ever did, and find its way from the inside to the outside. Granted, its ability to do this is still glacially slow...but compared to old R-12, it's like the tortoise (R-12) vs the hare (R-134a)

Not looking forward to getting a car with R-1234yf. 😕

OF
 
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...and the newer refrigerants operate at higher pressures on both sides of the compressor.

It's also a materials science challenge to find compounds that seal properly with newer refrigerants. R-134a can actually dissolve into O-ring material a bit more readily than R-12 ever did, and find its way from the inside to the outside. Granted, its ability to do this is still glacially slow...but compared to old R-12, it's like the tortoise (R-12) vs the hare (R-134a)

Not looking forward to getting a car with R-1234yf. 😕

OF
the 134a runs a lot hotter too...

1234yf is super expensive garbage thats flammable.
save the planet with your wallet... ra ra ra

seen a few posts of folks evacuating that crap and recharging with 134a.
possible with the right couplers.

in texas where it gets sweltering hot, that 1234 failed at science stuff just doesn't work under extreme heat loads.
 

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Discussion Starter · #36 ·
Thank you for all your posts.

Unfortunately I still have no idea how to actually solve my problem or what is wrong.

I'm beginning to think that my problem may be the fact that the a/c has NEVER been worked on, 21 years in November and 165,000 miles.

FYI, todays info, which is even more confussing. Temp 82, Humidity 70%. Steps are in order, manifold gauge readings were...
eng off and cold > 14L 20H
refg blead > eng on > compr did not start > 90L H(off)
compr on (jumped) > 63L 50H
eng off > 20L 25H
low off > refg can removed > eng on > compr on (jumped) > minus 3L 52H
eng off > 20L 26H

Please correct me if I am wrong in making the following assumption...

I think my compressor is failing or has failed because...

1. It will not start even with the low side pressure showing 90.
2. Even when jumped it does not increase the pressure on the high side at all.

Is there any test that I can do to know for sure if the compressor has failed? If necessary I can remove it to test it.

Because I have no idea which of the following components are failing or have failed, if any have or are, I am considering replacing all of the following items...

Compressor
Condenser
Receiver Drier / Desiccant Element

then adding Pag 46 Oil per Honda's repair manual, evacing the system (high & low) for 30 minutes, checking vac for another 30 minutes, if ok, closing the low and high, hooking up and bleading the refrig line, starting the engine, ac and fan on max, opening low side only, adding 30 to 31.7 oz of refrigerant by weight.

If there are any other things I should add to the list or do please let me know?

One last question...

Does a system vacuum (low and high open) holding at 30 in. for 30 minutes indicate that there are no leaks in the system or atleast no significant ones?
 

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Reality check:
Your first readings indicate either gauges that bear no relationship to real pressures, or a system that has only a scant amount of refrigerant, or both. Were there even a single ~14 oz. can in there, your Pressure should be appx. equal to your Temp in degrees F. The high/low should also be equal after sitting for any period of time.

You need to have basic knowledge of things like that before trying DIY MVAC repair.

Your last question again displays a severe lack of knowledge.

I really try to encourage DIY, and when I got into doing my own MVAC twenty years ago, I spent a lot of time on book learning and "listening" on an MVAC discussion forum. It's great that you have the FSM, but as it will tell you up front, it's written for proficient technicians, not as a "learn to".

I am not looking to dump on you, but you need on-site advice from someone with a good working knowledge of MVAC.

Stay well.
 

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Discussion Starter · #38 ·
Reality check:
Your first readings indicate either gauges that bear no relationship to real pressures, or a system that has only a scant amount of refrigerant, or both. Were there even a single ~14 oz. can in there, your Pressure should be appx. equal to your Temp in degrees F. The high/low should also be equal after sitting for any period of time.

You need to have basic knowledge of things like that before trying DIY MVAC repair.

Your last question again displays a severe lack of knowledge.

I really try to encourage DIY, and when I got into doing my own MVAC twenty years ago, I spent a lot of time on book learning and "listening" on an MVAC discussion forum. It's great that you have the FSM, but as it will tell you up front, it's written for proficient technicians, not as a "learn to".

I am not looking to dump on you, but you need on-site advice from someone with a good working knowledge of MVAC.

Stay well.
I just love it when someone says they don't want to dump on someone and then go right ahead and do it.
I fully understand what the pressures should be but they aren't, if they were I would not have started this post.
No further reply from you is either needed or desired.
 

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It's always amazed me that the highest degree of certitude is generally found among the truly ignorant, who not only do not know but refuse to learn.
 

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I just love it when someone says they don't want to dump on someone and then go right ahead and do it.
I fully understand what the pressures should be but they aren't, if they were I would not have started this post.
No further reply from you is either needed or desired.
Ted is the resident troll with a superiority complex, just ignore him.
 
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