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Pomai
June 9th, 2007, 03:25 PM
The summer heat's here and your car's air conditioner insn't quite as cold as it used to be. Chances are it needs to be recharged with refrigerant. Fortunately with today's newer ozone-safe R-134a (vs. R-12) refrigerant, if your vehicle is 1994 or newer, this is an easy and cost-effective D-I-Y project.

While there are a few brands and package kits of R-134a products out there, several of my friends had great results using Interdynamics Measure & Charge (http://www.id-usa.com/how_to_videos.asp) (a.k.a EZChill)...

http://www.96seven44.com/images/measurecharge.jpg
EZChill (a.k.a. Measure & Charge), purchased at Checker Auto Parts. Regular $32.99, with coupon just $19.99!

Measure & Charge/EZChill includes 18 oz. of R-134a refrigerant plus Oil (helps extend the life of your compressor) and Leak Sealer. The most important part of this "kit" is the inline pressure gauge, which provides the most accurate method of recharging your a/c system.

This is my experience using this product.

I'd recommend doing this job in the morning while the engine is cold vs. after you just got out of afternoon H1 traffic, as you'll be working over the engine while its running. This will also ensure that the A/C compressor is engaged (if your system is working properly), which it must be for an accurate gauge reading.

Begin by opening the hood and locating the LOW-SIDE SERVICE PORT, usually located on the accumulator with a BLUE PASTIC CAP, or on the larger-sized diameter metal tube with a BLACK PLASTIC CAP, often near the engine firewall...

http://www.96seven44.com/images/locate_lowsideport.jpg
On our 2003 Buick (GM), it was located near the firewall as shown above. It looks like an over-sized tire valve, with a plastic dust cap that easily screws off. Remove the cap and put in a safe place (don't lose it!).

Now start the engine and set the A/C to MAX and vent fan on high.

It's recommended to use safety glasses and gloves (I only had glasses).

Shake the Measure & Charge/EZChill can thoroughly, then attach the can's plastic slip-coupler onto the low-side port by pulling the sleeve back, push it completely onto the port, then lock the coupler sleeve into place.

http://www.96seven44.com/images/add_r134a.jpg

Before adding refrigerant, check the pressure gauge. If the needle is in the green (below 25 psi), it means the system is low and needs refrigerant. If the reading is in the yellow or red, it could either mean your compressor isn't engaged, or there are other issues that need to be looked at by a professional. Make sure the compressor is engaged during this procedure.

If gauge is in the green or lower blue, Press the trigger (under the safety cap) and add refrigerant. Continue to shake can as refrigerant is being added to system (this ensures oil/additives are properly dispensed with the R-134a). Release trigger in intervals to check gauge reading. Once the system is in the middle blue, preferably between 35 and 45 psi, you're done. Do not overcharge! Screw back on the plastic dust cap.

If your system is really low, you might need two cans. When I began, the reading was just at 25 psi (right above green). After filling the whole 18 oz. can, it went to 35 psi (middle of the blue).

The before and after difference and results? FANTASTIC!

I didn't have a thermometer on hand, so I can't give you numbers, but I'll say it like this.. before, it was just "cool". Enough for night time driving, but not quite enough for the hot daytime sun. I'd have to blow the fan on high to make it cool enough. Now it's ICE COLD. Like frost-bite cold if I put my hand in front of the vent, and I can comfortably keep the fan on low, even during daytime driving under the sun. Nice.

Recharging your car's A/C is super easy and convenient, and only takes about 10 minutes from start to finish. Best of all, it only costs $20 (with coupon) vs. probably $50 or (most likely) higher that would have been charged at an A/C shop.

Now that's cool.

*Refer to manufacturer for complete instructions and safety precautions.

joshuatree
June 9th, 2007, 07:57 PM
The gauge can also be disconnected from the can for future use as a standalone gauge too. Although I am curious, your '03 already needs a charge? I bought a can to use on a '96 Saturn but I wouldn't expect such a recent car to lose it's charge so soon.

Pomai
June 9th, 2007, 08:16 PM
The gauge can also be disconnected from the can for future use as a standalone gauge too. Although I am curious, your '03 already needs a charge? I bought a can to use on a '96 Saturn but I wouldn't expect such a recent car to lose it's charge so soon.Oops. No, it's a 2001 model, with odometer reading just under 50k.

joshuatree
June 9th, 2007, 08:28 PM
Oops. No, it's a 2001 model, with odometer reading just under 50k.

Ahh...sounds more reasonable. Otherwise, I would suggest you check for leaks in the system. ;)

Glen Miyashiro
June 9th, 2007, 08:42 PM
Wow! Thanks Pomai, that's a great tip. And your walkthrough is excellent! I've had coolant refilled a few times by the dealer; next time I need it I'm following your directions and doing it myself.

craigwatanabe
June 22nd, 2007, 09:38 PM
Make sure you don't overcharge the system. When I recharge using this product I use short blasts. And only charge when the compressor's clutch is engaged.

Overcharging can cause the solder relief on the receiver/dryer to pop. You can't reset these reliefs and the only way to correct this is to replace the unit.

On older cars that use the R-12 system, if the ac system is already atmospheric then you can buy a conversion kit from NAPA or even Checker Automotive. This kit has a special compressor oil that is compatible with both R-12 and R-134 allowing injection of R-134 into a system that contained R-12 freon.

It also has the necessary fittings to convert the R-12 fittings to R-134 and a decal that you place in your car's engine compartment indicating the car's been converted. Also in this kit contains the necessary hoses and gauges to fill your system. It's not necessary to evacuate if you use the purge method.

There was an urban legend that said that you couldn't use R-134 freon on older cars because the rubber seals would leak the smaller molecular composition of R-134. A few years ago the EPA did a study on this and found that if R-134 freon is used on a new system designed for R-12, then it would in fact leak. However on systems that ran R-12 then converted to R-134, the R-12 molecules would act like plugs thus allowing the R-134 to stay within the sealed pressurized system.

On these conversions the only unit that needs changing prior to conversion is the receiver/dryer as this unit contains the dessicant that removes moisture from the freon and is like a sump for most of the compressor oil. Receiver/Dryers should be replaced periodically anyway but not too often. I'd change it every 10-years or so.

I've done these conversions on many cars including my 1989 BMW and my 1986 Honda Accord. The Accord is still blowing 45-degrees outta the vent on a hot day like what we've had lately.

Pomai
June 23rd, 2007, 10:43 PM
Craig, you're practically a living encyclopedia. Amazing. You should be teaching classes at UH Hilo. Seriously.

I've got a question regarding a car's A/C compressor unit. How exactly does it work? I know it's a pump, but is there a piston, rod and crankshaft assembly in there, or is it like a Wankel engine?

I tried Googlin' it, but couldn't find a detailed breakdown of the compressor unit. Only explanations of the entire A/C system.

I'm hoping that by recharging my system with the Measure & Charge, the oil in the mix will help prolong the lifespan of my car's A/C compressor unit. I assume whatever moving parts are in there NEEDS lubrication, or it will eventually seize. I imagine the thermostat's control system for the compressor's cluth also is a key factor in its livelihood.

This is a good read (http://www.carcare.org/Climate_Control/ac_overview.shtml), but it still doesn't break down the compressor.


Make sure you don't overcharge the system. When I recharge using this product I use short blasts. And only charge when the compressor's clutch is engaged.

Overcharging can cause the solder relief on the receiver/dryer to pop. You can't reset these reliefs and the only way to correct this is to replace the unit.

On older cars that use the R-12 system, if the ac system is already atmospheric then you can buy a conversion kit from NAPA or even Checker Automotive. This kit has a special compressor oil that is compatible with both R-12 and R-134 allowing injection of R-134 into a system that contained R-12 freon.

It also has the necessary fittings to convert the R-12 fittings to R-134 and a decal that you place in your car's engine compartment indicating the car's been converted. Also in this kit contains the necessary hoses and gauges to fill your system. It's not necessary to evacuate if you use the purge method.

There was an urban legend that said that you couldn't use R-134 freon on older cars because the rubber seals would leak the smaller molecular composition of R-134. A few years ago the EPA did a study on this and found that if R-134 freon is used on a new system designed for R-12, then it would in fact leak. However on systems that ran R-12 then converted to R-134, the R-12 molecules would act like plugs thus allowing the R-134 to stay within the sealed pressurized system.

On these conversions the only unit that needs changing prior to conversion is the receiver/dryer as this unit contains the dessicant that removes moisture from the freon and is like a sump for most of the compressor oil. Receiver/Dryers should be replaced periodically anyway but not too often. I'd change it every 10-years or so.

I've done these conversions on many cars including my 1989 BMW and my 1986 Honda Accord. The Accord is still blowing 45-degrees outta the vent on a hot day like what we've had lately.

alohacandy
June 24th, 2007, 10:16 PM
Wow..a lot of good info. I have a 2003 Toyota Corolla with about 41,000 miles on it and the a/c hasn't been cooling for several months. One friend thought it was maybe a fuse for the fan so I took it to Kahala Shell and they said I need to have it recharged and quoted me a minimum of $80. If that's all it needs, then I may try to find that recharger and try it myself. I hate going to the Toyota service place here in Kaneohe...the last time I wanted to go for what I considered an urgent matter, they said to bring it in one week! WTF!! If it's urgent to me...I can't wait a whole week! Not sure what they would do if I just drove the car in and tried to get it serviced without an appt.
Sigh. I'll try the recharging first.

na alii
June 25th, 2007, 12:37 AM
My 2006 Corolla has a bad design that the rock or road debris got kicked up and hit the a/c condenser and punctured it. The freon leaked out. I bought a new condenser for $280.00 and changed it this weekend. You need a vacuum pump and a manifold gauge to remove the moisture from the system and then you can add the R-134A freon. I'm glad it's R-134A because I can buy a 12 oz. can at Walmart for under $7.00. The new condenser came with a can of refrigerant oil and it has a built in receiver dryer.

na alii
June 25th, 2007, 12:43 AM
Craig, you're practically a living encyclopedia. Amazing. You should be teaching classes at UH Hilo. Seriously.

I've got a question regarding a car's A/C compressor unit. How exactly does it work? I know it's a pump, but is there a piston, rod and crankshaft assembly in there, or is it like a Wankel engine?

I tried Googlin' it, but couldn't find a detailed breakdown of the compressor unit. Only explanations of the entire A/C system.

I'm hoping that by recharging my system with the Measure & Charge, the oil in the mix will help prolong the lifespan of my car's A/C compressor unit. I assume whatever moving parts are in there NEEDS lubrication, or it will eventually seize. I imagine the thermostat's control system for the compressor's cluth also is a key factor in its livelihood.

This is a good read (http://www.carcare.org/Climate_Control/ac_overview.shtml), but it still doesn't break down the compressor.

The old style compressors were the piston types. The compressors now days are the rotary type.

CranBeree
June 25th, 2007, 06:21 AM
or you could go to Polar A/C in Pearl City and pay 29.99 :D

alohacandy
June 25th, 2007, 11:42 PM
or you could go to Polar A/C in Pearl City and pay 29.99 :D

Cran! That's a great price...think I'll check them out. Anyone in particular I should ask for?