I think I just blew up my A/C

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It doesn't, which is why I decided to not install one, instead refurbishing my heater box and new core. Living in the northwest means fewer hot days, and it's not my daily driver. If I were to move back to Las Vegas I would kick myself for not having installed one, fresh air or not :)

 
Correct it is a recirculate only system. If I want fresh air I crack a window. I reused the vents and the defroster plenum, and had to make a new plenum to feed the two center vents. just a little tapered box to transition to the round hose.

 
Correct it is a recirculate only system. If I want fresh air I crack a window. I reused the vents and the defroster plenum, and had to make a new plenum to feed the two center vents. just a little tapered box to transition to the round hose.
Jeff. Could you take a picture of the evaporator unit under the dash? I am interested in how it looks on the passenger side by the kick panel and under the cowl vent.
Sent from my SAMSUNG-SM-G930A using Tapatalk

 
If I replace the broken hose do I need to do anything else besides pulling a vacuum, vacuum test, filling the compressor with oil and charge the system?

 
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Correct it is a recirculate only system.  If I want fresh air I crack a window.  I reused the vents and the defroster plenum, and had to make a new plenum to feed the two center vents. just a little tapered box to transition to the round hose.
Jeff. Could you take a picture of the evaporator unit under the dash? I am interested in how it looks on the passenger side by the kick panel and under the cowl vent.

Sent from my SAMSUNG-SM-G930A using Tapatalk
Here's mine going in with the dash completely out of the way.

The complete CAA HVAC inside unit is smaller than the factory heater core/exchange alone (mine was a non-A/C car).

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Not the best pic - sorry.

Also - the sentiment on not being able to use R-134a in older HVAC systems is not entirely correct.  I believe the common misconception is that it might not be recommended - mostly due to a chance of the R-134a and R-12 compressor oil mixing and creating the 'black death' sludge. 

However, I've had personal experience with at least a dozen older systems having been upgraded to R-134a.  My '95 Honda Civic for one - it blew icicles once I removed the factory blocking plate from in front of the condensor as long as the rpms were above 1100 or so.  As well, my pal Jim (who happened to be a certified A/C technician) converted his '77 Jimmy's factory A/C to R-134a with no issues - you could hang meat in that truck on a hot day.  My Mom's '96 T-Bird was converted over as well - no issues.  Her '89 Dodge Dynasty - same deal, no issues.  Also helped a bunch of customers at the Auto Hobby Shop covert their systems over the years - no issues... ever. 

The key is to ensure the system is absolutely clean and purged before introducing the new refridgerant and oils.  Having an actual A/C refridgerant capture/fill machine is a huge help.  Especially, when checking for leaks - stick it on 'vacuum' and leaving it hooked up for a half hour, then fill the system without disconnecting anything.  Works like a champ.

 
Correct it is a recirculate only system.  If I want fresh air I crack a window.  I reused the vents and the defroster plenum, and had to make a new plenum to feed the two center vents. just a little tapered box to transition to the round hose.
Jeff. Could you take a picture of the evaporator unit under the dash? I am interested in how it looks on the passenger side by the kick panel and under the cowl vent.

Sent from my SAMSUNG-SM-G930A using Tapatalk
Here's mine going in with the dash completely out of the way.

The complete CAA HVAC inside unit is smaller than the factory heater core/exchange alone (mine was a non-A/C car).

attachment.php


Not the best pic - sorry.

Also - the sentiment on not being able to use R-134a in older HVAC systems is not entirely correct.  I believe the common misconception is that it might not be recommended - mostly due to a chance of the R-134a and R-12 compressor oil mixing and creating the 'black death' sludge. 

However, I've had personal experience with at least a dozen older systems having been upgraded to R-134a.  My '95 Honda Civic for one - it blew icicles once I removed the factory blocking plate from in front of the condensor as long as the rpms were above 1100 or so.  As well, my pal Jim (who happened to be a certified A/C technician) converted his '77 Jimmy's factory A/C to R-134a with no issues - you could hang meat in that truck on a hot day.  My Mom's '96 T-Bird was converted over as well - no issues.  Her '89 Dodge Dynasty - same deal, no issues.  Also helped a bunch of customers at the Auto Hobby Shop covert their systems over the years - no issues... ever. 

The key is to ensure the system is absolutely clean and purged before introducing the new refridgerant and oils.  Having an actual A/C refridgerant capture/fill machine is a huge help.  Especially, when checking for leaks - stick it on 'vacuum' and leaving it hooked up for a half hour, then fill the system without disconnecting anything.  Works like a champ.
Great pic. Thanks. Are you able to keep the vent flapper that was on the passenger side in your car to let outside air in if needed?

 
How much oil would be needed when you have a blow out like that?
Good question. When I filled my system a month ago, I just filled the compressor from the top fill hole to the level indicated in the manual. I was planing on doing the same this time, but I don't know if there is a way of knowing how much oil is left in the other parts of the system to know if you add more or less. Anyone knows?

 
Jeff. Could you take a picture of the evaporator unit under the dash? I am interested in how it looks on the passenger side by the kick panel and under the cowl vent.

Sent from my SAMSUNG-SM-G930A using Tapatalk
Here's mine going in with the dash completely out of the way.

The complete CAA HVAC inside unit is smaller than the factory heater core/exchange alone (mine was a non-A/C car).

attachment.php


Not the best pic - sorry.

Also - the sentiment on not being able to use R-134a in older HVAC systems is not entirely correct.  I believe the common misconception is that it might not be recommended - mostly due to a chance of the R-134a and R-12 compressor oil mixing and creating the 'black death' sludge. 

However, I've had personal experience with at least a dozen older systems having been upgraded to R-134a.  My '95 Honda Civic for one - it blew icicles once I removed the factory blocking plate from in front of the condensor as long as the rpms were above 1100 or so.  As well, my pal Jim (who happened to be a certified A/C technician) converted his '77 Jimmy's factory A/C to R-134a with no issues - you could hang meat in that truck on a hot day.  My Mom's '96 T-Bird was converted over as well - no issues.  Her '89 Dodge Dynasty - same deal, no issues.  Also helped a bunch of customers at the Auto Hobby Shop covert their systems over the years - no issues... ever. 

The key is to ensure the system is absolutely clean and purged before introducing the new refridgerant and oils.  Having an actual A/C refridgerant capture/fill machine is a huge help.  Especially, when checking for leaks - stick it on 'vacuum' and leaving it hooked up for a half hour, then fill the system without disconnecting anything.  Works like a champ.
Great pic. Thanks. Are you able to keep the vent flapper that was on the passenger side in your car to let outside air in if needed?
I could've probably done that, but I think the driver side might be better.  Then again, if the flapper isn't in working order for one side of the other, you just pick the one you want.  I actually made a 2nd plate and blocked both off... although, I wish I would've reused my driver side flapper (I think that's the one that still works).

 
Trying this question again about oil. After I replace the broken hose and pull vacuum, should I just fill the compressor with oil to the recommended level? When the refrigerant leaked through the hose there was oil everywhere. Is the amount of oil left in the system important?

 
I am not sure on the amount of oil you should add. I thought that the oil pretty much gathered in the compressor and slight amounts get in the system.

I will look at the Ford shop manual today and see what they say.

One thing that has me puzzled on the whole thing is. Why did the safety pop off valve on the compressor not blow if it was over pressure? That should be the weak link to prevent hoses from blowing. It is on the back side of the compressor. 

Might get back into mine today. Once I find the leak and repair I will vac again and go back to the Dura Cool material. 

An engineer from a local business that produces cooling units told me that the highly refined propane products do preform much better than R-134 or R-12. Guy had 22 cans of R-12 on CL here for $20.00 a can and cheaper if you bought more. It was all gone in an hour, lol.

I am still struggling with the fact that the new green O-rings I find are metric and the unit is actually inch. When I pull a hose or connection open the green rings look horrible. Do you have place to get the inch O-rings? Putting a square peg in a round hole is just not right.

 
I am not sure on the amount of oil you should add. I thought that the oil pretty much gathered in the compressor and slight amounts get in the system.

I will look at the Ford shop manual today and see what they say.

One thing that has me puzzled on the whole thing is. Why did the safety pop off valve on the compressor not blow if it was over pressure? That should be the weak link to prevent hoses from blowing. It is on the back side of the compressor. 

Might get back into mine today. Once I find the leak and repair I will vac again and go back to the Dura Cool material. 

An engineer from a local business that produces cooling units told me that the highly refined propane products do preform much better than R-134 or R-12. Guy had 22 cans of R-12 on CL here for $20.00 a can and cheaper if you bought more. It was all gone in an hour, lol.

I am still struggling with the fact that the new green O-rings I find are metric and the unit is actually inch. When I pull a hose or connection open the green rings look horrible. Do you have place to get the inch O-rings? Putting a square peg in a round hole is just not right.
David, I didn't know there was a safety pop off valve in the compressor. I am still puzzled on how the actual coupling nut of the hose was pushed out. I want to fix the hose and then pull a vacuum to check if there are any other leaks. I have not found a local place that can custom make/repair a hose for me so I may have to send it to Cold Air in Florida, who fixed my hoses earlier this year.

I got a kit with bunch of those o-rings and they fit. I didn't pay attention if they were metric or SAE. I bought the kit at Farm & Fleet, which is a regional chain. There are a bunch of kits in Amazon but I don't know if they will work for you.

 
You could try calling a couple reputable restoration shops or even a hydraulic hose repair place as they usually have the equipment to crimp AC hoses as well. I know Sadler Powertrain down here can crimp AC hoses.

 
You could try calling a couple reputable restoration shops or even a hydraulic hose repair place as they usually have the equipment to crimp AC hoses as well. I know Sadler Powertrain down here can crimp AC hoses.
Thanks. Good idea, but it didn't work. I just went to a place that works with hydraulic systems. Initially on the phone they said they may be able to fix it but after seeing it they said they can't due to something to do with the location of the soldering.

 
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For those following this threads, what are other ways to create and over pressure condition? Could a contaminated system get clogged and overpressurize to the point of bursting a hose? As mentioned above, it is puzzling that the low pressure coupling nut came off. There are no marks or visible damage of the threads. Could it unscrew itself all the way and allow the system to be contaminated? Weird, however, I don't think this would be the case since the A/C was cool just until the 6,500 rpm moment and I assume that if the low pressure hose would have disconnected the high pressure side would have not overpressurized.

 
when you say low pressure hose I assume you mean between the Evaporator and the compressor. On my 94 Bronco, there is a relief valve on the fitting right where it connects to the compressor. I dont remember if theres one there on my Mustang or not since that is a project I havnt started yet. I have to flush it and convert it over to 134a. Its hard to say what happens inside that tube at 6500rpm. I would have thought the hose coming off the condenser would break first, seeing how on my bronco its a solid aluminum line to prevent it from blowing up. I know on the mustang its a hose though. Its almost like your clutch stopped working and the high pressure went thru the orfice and overpressurized the low side hose, if the clutch disengaged, it is at least conceivable that pressure would build up and rupture the hose, especially if it has no relief valve and the compressor was stopped leaving the pressure no where to go.

Just some random thoughts, take it or leave it, I probably am wrong anyway, but its worth considering.

 
when you say low pressure hose I assume you mean between the Evaporator and the compressor.  On my 94 Bronco, there is a relief valve on the fitting right where it connects to the compressor.  I dont remember if theres one there on my Mustang or not since that is a project I havnt started yet.  I have to flush it and convert it over to 134a.  Its hard to say what happens inside that tube at 6500rpm.  I would have thought the hose coming off the condenser would break first, seeing how on my bronco its a solid aluminum line to prevent it from blowing up.  I know on the mustang its a hose though. Its almost like your clutch stopped working and the high pressure went thru the orfice and overpressurized the low side hose, if the clutch disengaged, it is at least conceivable that pressure would build up and rupture the hose, especially if it has no relief valve and the compressor was stopped leaving the pressure no where to go.

Just some random thoughts, take it or leave it, I probably am wrong anyway, but its worth considering.
Interesting theory. Actually, what happened is two-fold. The high pressure hose (compressor to condenser) burst. But I also found that the coupling nut that attaches the low pressure hose to the compressor was off (evaporator to compressor).

 
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