AC question for group

[Rob94]

You know, for someone who claims to know so much about air conditioning refrigerants, you sure are having a difficult time finding and fixing a seemingly small leak. What do you say we get back on topic and you just use the reccomendations to fix your problem.

 

[Mark in PDX]

You know, for someone who claims to know so much about air conditioning refrigerants, you sure are having a difficult time finding and fixing a seemingly small leak. What do you say we get back on topic and you just use the reccomendations to fix your problem.

I'd love to.. But when the leak drops only .5lbs in 2 weeks, none of the sniffers I could lay hands on could find it.. I have the car back at the Ford dealer where they told me, "It holds a vacuum, must not have a leak".. sigh...

I asked them to replace the compressor as the only thing we can figure is that it is leaking around the shaft seal when it is running, but not bad enough to show up on a sniffer.. also asked for a dye to be put in... but who knows what they'll really do.

 

[shojuan]

Why don't YOU put dye in it? Sheesh, how hard can that be?

 

[Mark in PDX]

I wish it were that simple.. we've been fixing this thing for 3 months or more now.. Each time we've "found" a leak and fixed it.. Each component has basically failed in succession, leaving us with all new parts except the Evap core and we stuck a sniffer on that and got no change while running the AC for 2 hours...
We figured if it is the Evap core, they'll tell us, otherwise it's got to be the compressor as it ran for 3 weeks before that started leaking and that is the only component that has been worked on since that point.
Dye just wasn't needed til now and we're betting on a shaft leak.

 

[Rob94]

Upon doing some research on the refrigerant 414, your problem is quite common. That refrigerant is designed for heavy duty truck applications, ie diesel units. There components are designed for much higher running pressures. Regardless of your sources, I'd beg to differ that if you got rid of that stuff and just coverted to 134a, your problems would be fewer, if not solved. I have 134a, and I routinely get mid to high 30 degree air out of the center vents.

 

[Mark in PDX]

Can you point me to some sites I can research this on? I didn't find anything like that when I did my searching previously... And if you did recently, I'd love to go read up on it..
Please advise.
Mark

 

[rangerj]

A couple of suggestions;

The tell tale sign of a leak is the oily black dirt. Do you find this behind the clutch coil?
If you do have a shaft seal leak it will require special tools to remove and replace the seal. The tools are specific to the 10P-15-F Nippondenso compressor. Other seal removal/installation tools will not work. That is the tools for the 10P-15-C, and other Nippondenso compressors, will not work on the 10P-15-F. Take it to an A/C shop that has the proper tools for the compressor, or spend about $125 for the tool set for this compressor.

Dissassemble your system and chemically clean out all of the components except the compressor. Drain the compressor of its oil by letting it sit overnight. Replace all of the seals, ie "O" rings. I suspect that the R-414 and/or its oil have had an ill affect on your seals.

The condenser will commonly get pin hole leaks in it from corrosion and/or being hit with stones and other road crap. Have it pressure tested. If it is OK, clean it or have it cleaned. If any black crap comes out of it plan on replacing the accumulator/dryer.

If you suspect the leak is in the evaporator core have it pressure tested. It also should be cleaned, if it tests out good.
Best wishes, rangerj

 

[Mark in PDX]

Everything in this system is BRAND NEW... I think it has all been replaced except the core (including the compressor by ford) in the last few months.. so we haven't had time to build up any oily black dirt..
I suspect the leak is in the compressor because we can't find any trace of leaking freon anywhere in the car or engine compartment with the car just sitting.. when running we get some traces near the compressor, but it is intermittent...

 

[Mark in PDX]

Great,
Dealer calls me back just now.. Well, your system hold a vacuum just fine.. Can't find a problem...
I point out that they said they would leak test it and the tech discloses that they don't work on R12 cars anymore, they require conversion to R134 to do leak tests and dye checks...
sigh
what a waste of time...

 

[rangerj]

Pull the Clutch assembly and look for signs of oil. If everything is new it should be clean, except for the R414 residue and R414 oil, if it is different than the other oils.

Do the research to determine if the R414 will have a bad affect on the system if you put R-134a into it. That is, is the R-134a and R414 compatable? If the two are compatable you should be able to fill the system with R-134a, and the appropriate amount of oil. There should not be anything else to do for the "conversion".

If the two refrigerants are not compatable, then the system components need to be chremically cleaned before filling it with R-134a, and R-134a compatable oil. rangerj

 

[Mark in PDX]

R 134 is not compatible with R414. R 414 is a replacement for R12, direct oil compatible..

I don't have anyplace to take the car apart at the moment. It is raining (so I don't need the air now probably until next summer (oregon)... But by then, they'll say the part isn't under warranty.. so I gotta get this figured out. I am going to pick the car up and will have a buddy who does AC work dump Dye in the system for me.. then I'll get it topped off and run it for a few days then blacklight it... That should tell me what to replace..
IF it is the compressor, the dealer said they would replaced it again... if it isn't, then I'll at least know what part to swap again.
sigh
this is all taking too long.. it shouldn't be this big a deal to fix a stupid hole in the ac system.

 

[Rob94]

I stand by my original comment. It is a pain because you are using a refrigerant not designed for use in an automotive air conditioning system. I've researched this R414 refrigerant, and it seems that many people have had a similar problem. The pressure is too high, and blows out the head seal, or shaft seal, in the compressor.

 

[Rob94]

Found the following information on R414a. Just do a google search on it to find similar articles. I've cut and paste pertinent information.


R414A is a hydrochlorofluorocarbon/ hydrocarbon blended product. Cools exceptionally well; especially in systems with poorly designed condensers (small/ poor airflow). Works with mineral oil and is non-toxic. Does require barrier hoses with "liner." If your system leaks, the blend will separate and may cause compressor failure due to loss of oil circulation. Availability is limited and if not available you will have to live without A/C until you find it; or convert to R134A. More expensive than R134A and requires a license to purchase. Autofrost or McCool/ Chill-It are brands.

On the same site, I found this statement:

Which one should you use? The choice depends on why you actually need freon to begin with. R414A is the refrigerant of choice if you have a complete, clean system that was working fine with R12; and for some reason you lost the R12. For example a hose blew, you hit something and broke the condenser, had to pull the engine out, etc. If the system was working well with R12, you can simply change the hoses for barrier-type hoses, evacuuate the system then charge in the R414A.


It would seem to me that if you did not change out all of the hoses to these "barrier-type" then that could very well be your problem. If the refrigerant is indeed mitigating through the hoses, it would do so at such a slow rate as to be pretty much undetectable. For reference, I'm linking the site I found the information from. Good luck.

http://home.hiwaay.net/~davida1/aircond.htm

 

[Mark in PDX]

Think I found the problem.. turns out that when they replaced my compressor, they never put the oil into it.
I told them I was refilling it with R12, so to set it up for that but don't put any freon into it... Seems that they didn't follow instructions and didn't tell me that they didn't put oil into it, so we all assumed (doh!) that they did... Now the shaft seals are gone... sigh
I hate not doing the work myself...

As to the pressure issue, I have talked to Hot Shot about that, and they show the spec for hot shot matches R12 almost exactly.. There is very little difference,and it certainly doesn't require higher pressure than R12... I know there have been some variants out there, but Hot shot is setup as a direct r12 replacment. It does require barrier hoses, or the Freon will leak out over about 5-6 years (quote from the company).. But since it is environmentally friendly, I am not worried about that. They said that any leak in less than 5-6 years is a bad seal or o-ring somewhere.
I'll take a closer look at that site you linked too though.. but my 'google' searches on r414 came up with more healthcare than AC.
later

 

[roswell998]

Think I found the problem.. turns out that when they replaced my compressor, they never put the oil into it.............

As to the pressure issue, I have talked to Hot Shot........

If there was no oil and the compressor was running dry, it would have almost certainly seized up by now rather than merely wearing out shaft seals.

Talking to Hot Shot..........they are in the business to sell R414. Of course they are going to endorse it!

To narrow the search enter both words "R414 refrigerant" (but not in quotes). The following is cut and pasted from one of the spec sheets:

"R600A - 1.9%, R142B - 9.5%, R22 - 50%, R124 - 39%. The resulting “blend” (R414B) has a Boiling Point of -28º F. and an ODP of .034."

The operative word in the paste above is "blend". As R414 leaks out (even normal long term seepage) the different molecular structure of the various components of the blend will leak at different rates, thus significantly affecting the overall properties. That's a serious problem.

Bottom line................unless I missed something, I don't recall anyone on this forum ever recommending anything other than staying with R12 or converting to R134. There is a lot of experience behind this forum and I for one tend to lean very heavily toward the advice given.

Bottom, bottom line.........Either put in R12 or R134, or stay with the R414 and live or die with it.

If you elect to stay with the R414 then either GOOD LUCK or RIP.

.

 

[Mark in PDX]

Yeah yeah.. I get that point.. I am not deaf (or is it blind)... My problem really isn't the refrigerant, it is the LEAK!.. Doesn't matter what I put in, it leaks out over about 2 weeks.. And the bloody dealer says, "Hold a vacuum fine, no problem found"... grr...

With R12 costing me an arm and a leg, I don't think I can afford to stay with R12, r414 is about the same cost as r134, but had the same cooling properties vs. the 20% less efficient than R134.. that was why i wanted to give it a shot.. But with all the headaches since this is a leaky system, I am just going to have to abandon that and go with the r134 I guess...
Anyone got a recommendation on a preferred conversion kit?
Mark

 

[shojuan]

Don't feel bad about having to go with R134A. First off, get the dealer to give you another new compressor. They ****** up if they installed it without oil and it burnt up because there was no oil and they didn't give FAIR warning that you needed to add the oil that they didn't add.

Next up, with all new AC parts a 134A SHO AC system will blow very cold air when the charge is tuned just right. My understanding is, and I certainly hope somebody will correct me if I'm wrong, that Ford didn't bother to switch to a bigger condensor setup for the factory 134A V6 SHOs. It's all the same AC parts on the R12 or R134A factory equipped SHOs. At least Ford felt the existing combination of parts was adequate for the 134A switchover. Plus several folks here have really nice cold air with their 134A systems.

Mine is a DIY retrofit. I STILL have the original R12 mineral oil in my system and it's basically just sitting in the bottom of my condensor taking up valuable space. Plus I probably have an ounce or two more polyol ester oil than optimal in my system. Somewhere along the way I got a slow leak after the conversion I did 4 years ago or so. Probably just some rubber drying out because I stopped running my system frequently when the AC clutch wore out and coil grew flakey. I replaced the clutch and coil and recharged. This time I have at least a low side gauge. When I did the initial retrofit I had no gauges. Just vacuumed the system myself with a garden hose aspirator for several hours and added the recommended charge (85% of R12 charge worth of R134A + 8.5 oz (.5 ounce too much!!!) ) that the Interdynamics kit recommended. 4 Years ago it worked great keeping my precious German Shepherd Dog cool on the 440 mile trip to San Diego in 100 degree heat. That's good enough for me.

Anyways, with my current fresh charge I'm getting ~49 degree air with AC on MAX and full fan. Not the greatest but it DOES keep the car cool in 90+ degree weather. It's cool enough I don't have a hint of worry transporting my double coat wearing dog to the lake in August weather. That means something to me. The air DOES feel cold.

If I lower the fan to low + 1 then I get 45 degree air....I've had as low as 42 with all but the center vents closed and the fan on less than high. I don't think I have the optimum amount of 134A in there and I have some reduced capacity from the mineral oil weighing down the condensor bottom and some extra R134A oil in there. Brand new parts and clean system should work real nice with the R134A.

Sure the hotshot sounds like it would be even better in theory. And I'm sure when everything is going right and everything agrees then it is. BUT it is obviously not idiot proof. That quality is a VERY important factor. Sadly you've learned the hard way through no real fault of your own. If you choose to fight it to the end with the 414A hotshot then the fault WILL become your own, lol!

Here are some more analogies to give you some perspective on your dilemma: Often in computers there are "simple" more efficient ways to get something done. And often those approaches aren't idiot-proof and will burn the average smuck. I can't recommend to my mom the same method to attack a computer issue that I wouldn't hesitate to take myself. Because my way isn't idiot proof. 9600 bps stand alone fax machine. Idiot proof. 14400 bps fax modem, can offer better performance. But you will get burnt because it's NOT idiot proof. A guru will get burnt when he needs the damn thing to work right now (time crunch) without having to go through the whole ritual that the device demands. So yes, idiot proof is good for the experts even when the day to day performance promised is less. I had another little analogy in mind several minutes ago but I forgot...It's late, I'm tired, and my sleep sleep glass of wine is kicking in. You probably see the point I'm trying to make by now. Idiot proof means you don't have to burden yourself with the details and caveats that would not only be overwhelming to a layman but would often be a complete nuisance to an expert. From what Rob and others have mentioned in this thread it appears that for automotive AC parts R-134A is going to be far more idiot proof that 414A. 414A definately is NOT as idiot proof as R12 used to be, that's for sure.

Good luck.