seen

Hi guys,

I have an AC problem.. a few months ago I discovered I had a leak in the condenser, so I replaced it. Yesterday I received my hoses/gauges etc. to attach to the low/high side ports. I pulled a vacuum for a half hour to make sure there was no moisture in the lines, then left it for another 10 minutes to make sure the vacuum held. It did.

Here is my problem. I know my car holds 19 oz of freon. I bought 2 12 oz cans from a local store, and I started filling my AC with the first can with the engine off. High side port was off. Low side port was open. My readings near the end of the first can are as follows in 95F weather with the engine running full AC:

high side: 110-120 psi
low side: 85 psi

When I rev the engine to about 1.5k RPMs, the low side drops to about 60. I know the low side is supposed to be around 30-40 psi. Can anyone tell me what's wrong, or is this normal during a recharge? Many thanks..

fcm

What is the MM&Y of the car?

When charging into a vacuum it is done through the high side not the low side, low side charging is done by using the A/C compressor to "draw" in the refrigerant, [bumping].

You said, "I bought 2 12 oz cans from a local store" cans of what?
Do you have a name, or a link?

Please tell me it was not RedTek or Duracool and it was 100% R134a without anything else, [sealers].94

seen

Doh! ><

I used the more expensive arctic freeze r134a with the sealer in it. I have a 2004 civic. Here is the link to the cans I bought:

http://shop.advanceautoparts.com/web...T|GRP2004A____

I have a question about the high port side charging though. Everywhere I've seen it says to always charge on the low side. Even the instructions which came with the hoses say when empty, charge the low side with the engine off until you hit 50 psi. Now I'm confused

I should be alright though if I re-vacuum the system and start over with regular r134a freon yes? I bought this today:

http://shop.advanceautoparts.com/web...T|GRP2004A____

fcm

All the DIY systems charge through the low side, The DIYer does not normally have a vacuum pump.

The problem with the DIY systems is the sealers and the hydrocarbons they contain, they contaminate the system.

I did not know you could buy R134a refrigerant without proper certification, you can not in Canada.

The links to the products you got do not give a description of what exactly is in the cans
The Arctic Freeze is self explanatory, "Synthetic R-134a" pretty sure there is no R134a in the can at all, as for the other can, it would seem it is R134a, but I would like to see the content label.

Proper A/C charging is done by weight not by pressure, I would have to check to be sure but my guess is that your 04 Civic takes 16oz of refrigerant, I will check. 94

PS If you have already contaminated the system there is no way to decontaminate it, you can flush out the sealers, clean the expansion valve but you will never get rid of the hydrocarbon contamination, however this does not mean you can not get the system working properly again. 94

Duane_in_Japan

For folks who DIY and are not sure what they are doing it is recommended to put in an amount that is about 70% of what the label on the car calls for then add little by little until the output at the vents stops getting cooler, this would also require a good thermometer stuck in the vents. I like to test at 2000 RPM although 1500 is accepted as a good range. If you allow vacuum to suck the freon into the low side, you run a risk of liquid killing the compressor upon startup, you need to let it sit for some time to evaperate (turn into a gas state) within the system prior to starting the engine. DIY cans from the store are called Death Kits, beware. Just use real R134a and service by weight, cant go wrong.

seen

You guys are awesome, thank you for the tips!

I do however know that my car holds 19 oz of r134a, because I was a sucker the first time and had my AC professionally diagnosed.. They charged my car up and quoted me 19 oz at $3.95 /oz. Then with labor, dye, oil, they charged me all together around $150. After following the dye, they determined a condenser leak and wanted to charge me $500 more to fix it and recharge the system again.

Had I known you could pick up all of the diagnosing equipment for around $200 (including pump) I would have just done that from the start. I picked up a condenser plus O-rings online for about $100 and replaced it myself. I will try flushing and recharging with the basic r134a and post my results

Duane_in_Japan

When you changed the condensor, did you add more oil, one more oz. should be good, if you can get real R134a with oil OR with oil and dye, fine, but dont use sealer. You stated flush, dont flush through the expansion valve, rec/drier or compressor or muffler if one of your hoses has a muffler, if you actually flush, you will need to add even more oil to the system. All new orings for everything you disassemble, lube the orings with the correct oil before re-assembly. A cheap vacuum pump should be given more time to vacuum, an hour should be ok and do a longer leak check also. A system that does not leak under vacuum does not mean that it wont leak under pressure, that is where the dye comes in.

EDIT: If your condensor does not run through one constant tube then flushing it wont help much, most dont these days.

fcm

$3.95 an oz, what a rip, We charge $2.00 an oz and that is still a good markup, [fair].

$500 for a condenser, also a rip, $100-$200 for condenser, probably .5 hr to swap it out.

We would never charge again for a recharge and refrigerant, [within 1 year] if we missed a leak, yes the condenser and the labour to install it but not the refrigerant you lost because we could not find the leak. 94

seen

Okay.. Here are my findings:

I vacuumed the system for 1 hr this time. I hooked up the basic r134a and I didn't even get through half of the can before the pressure on the low side started rising up to about 40. Is this normal? When it got to around 45 or 50, I shut off the port and turned the car on full AC, and opened the port again. My readings from that point, whether the port was open or closed, are as follows:

High side: 60 psi
low side: 50 psi

This is even worse than the first time. I would have just let the can go (ignore the pressure and go by weight) like you guys said, but once the pressure gets high enough the r134a just doesn't want to flow into the system anymore, and I didn't want to waste an entire can of r134a like the first time. Should I keep going? Better question, how much pressure can the low side hoses take before they get damaged, if at all?

seen

Alright. Well after some google searching, it looks like my compressor's failed. Great

DCFIVER

Yeah when the pressures are about equal on both sides it usually means a compressor failure. DIY cans of 134 all contain some type of sealant. this probably damaged your compressor. Like was stated early you will never get all of the sealant out of the system. Also flushing with any type of flushing agent is also not reccomended as the flushing agent is also a contaminant that can never be completely removed from the system. Flushing with liquid R134 is the only OE approved type of flushing that will not cause any damage.

fcm

Yes and no...

Yes compressor is most likely N/G, however an A/C flush will remove the sealants and the flush will evaporate leaving nothing behind, unfortunately it will not remove the hydrocarbon containment.

OP, did you charge through the high side this time, and as asked did you add oil? 94

seen

It was done through the low side. I don't know the proper procedure on how to charge it through the high side.

I'm going to just take it to a garage and have them look at it again. I hope the compressor isn't damaged. I hear it, there isn't any whistling or whatnot to indicate that the clutch has slipped, etc..

The strange part of it is that because the pressure on the low side shot up so fast, the compressor kicked in after filling only about 6 oz of r134a into the system. That's not normal either right?

DCFIVER

No the AC flush does not evaporate. This is why there is NO OEM that will allow for flushing with any kind of agent other than liquid R134. Many techs and shops are not aware of this...

Duane_in_Japan

If you service into the low side, the vacuum may have drawn in that 6 ounces so quickly, sounds like it did, that it was still in a liquid state and it may have damaged the compressor, but if you let it sit for awhile, it will turn into a gas state again and you can continue to service like a normal top off.

This is where you are now, continue to top it off to the correct amount, if the AC System is 45 PSI and the cold can is 45 PSI then the can wont empty, you have to put it in a bucket of hot water to heat up the can and create more pressure, dont turn it upside down. You also need to keep the engine up between 1500 and 2000 RPMs for proper service, top off that is.

Make sure that both your gauges, HI and LO are not both open at the same time, a mistake many people make.

Now remember, before you tighten the can onto the hose, open the LO valve first to allow some freon in the car to leak out to purge the hose of its moist atmospheric air, screw the can on all the way to stop the leak, puncture the can and service like normal, warm up the can to allow more gas to get into the system but dont put in on the exhaust pipe and dont dunk the hose into the hot water in your bucket.

Service the proper amount by weight then evaluate the job by telling us both LO and HI pressures with both valves closed at 1500 to 2000 RPM. Let the car run for a little while to stabilize the gas around the system before troubleshooting. I have had to drive a couple of miles to circulate gas on several occasions (Nissan Vans are bad for this).

seen

OK! I come bearing better news.. (I think?)

I put in a full 12 oz can. I ignored the meters, and put as best I could another half can to make 18 oz. It's probably still a little less, but here is my findings. With the engine on and the AC full at idle, I get:

low side: 89 psi
high side: 110 psi

When I rev the engine to about 2k rpm, I believe the meter said:

low side: 55-60 psi

At idle, no cold air would blow. But when I rev'd the engine up to 2k, cold air started coming out. The higher I rev'd the engine, the colder the air got. Thoughts? Should I add more? Less? Is the compressor still classified dead? Many thanks!

fcm

55-60 PSI on low side is still too high, compressor is still an issue.
Had a customer today with pretty much the same numbers as you do, [02 accord] we had installed a compressor he had got from the pick&pull and I had told him at the time the compressor was weak, [gauges do not lie] but it was working and he was satisfied, now it's a little hotter out and he is back insisting there must be a leak, we install gauges and it shows the charge looks good, engine off, at idle RPM low side was 90 and high side was 115 at 2000 RPM we got 65 and 120, told him it was the compressor he insisted it was a leak, so I "bumped" an once no change in low side, high side went up 5PSI, [head pressure] no change in vent temp. [12 degrees C].
He was convinced the charge was still low so I hooked up the Binford and recovered 1.45lb out of a system that has 1.44lb charge, recharged it with 1.44 lb, no chance in gauge readings and still 12 C from the vents, he is on his way to pick&pull to see if he can find another one, [compressor], the one he has is more then 2 weeks old so no exchange, he will have to pay for the next one, pay us to re&re it and a recharge, take a chance again that it is not a contaminated pump, and although we will not charge him for the refrigerant even the recharge as it will pretty much be his refrigerant we will be putting back in, all bets are off if the compressor is contaminated.

Long story short, if you have to replace the pump, [most likely] buy a reman from a Cooling Depot retailer, replace the filter/dryer, [buy from same place] that way you at least have warranty on the pump for a year. 94

seen

I might consider doing that, but to be honest when the mech told me I'd need to pony up $500 for a condensor replacement (telling me I was lucky it wasn't a bigger problem) I pretty much dismissed the idea of having my AC fixed.

I tried to buy the equipment to see if I could fix the problem myself, but now that I know I created an additional compressor problem (Online prices are $400+) I'll probably just keep my current configuration until the compressor completely dies. At that point, no more AC for me..

Thanks everyone for your input. Hopefully the next time I do this I won't be such a dumbass.

Duane_in_Japan

Put in some more freon, we will also need you HI side pressure at 2K RPM next time too, just add a little and go around the block, check pressure and temp out the vents, we know you are close to a full load.

fcm

Ditto the above^^^ 94

seen

So I have a bit of an update for those of you who are interested:

The other day the AC stopped pushing out cold air all together, so I hooked up the meters again tonight and...

low side: 85 psi
high side: 105 psi

When I rev the engine with max AC, the meters do nothing. lol. I can hear the compressor kick in when switching it on, but after that the meters remain the same no matter how high I rev the engine.

I guess it's a pretty safe bet now that the compressor just fell off its last leg huh.. Cheers

donmontalvo

I just joined this forum, please be easy on me.

This is exactly my problem! My AC works fine when I'm moving. But when I'm at a light and the RPMs drop to 1000 or so, the AD blows warm air.

I have an appointment with Honda to reload the AC. Their guess is it's low. But they want around $200 to do it. Sounds like it can be done for cheaper. Would it be worth the risk to take it to KwikKar or some other car repair shop?

Don

--
Don Montalvo
Coppell, Texas
2002 Honda CR-V LX (155K as of Jun 2010)

DCFIVER

yes any decent repair shop should be able to recharge your system for a cheaper price than the dealer. What you dont want to do is try to do it yourself with your local auto parts store refrigerant. That will lead to problems with your AC system...