A/c Conversion - R-12 To R-134... Advice?

[tckcumming]

My local auto air conditioning shop has recommended that I convert my '93 es300 A/C system from R-12 to R-134 refrigerant. My HVAC system is working fine now, the only (minor) issue is that sometimes the A/C takes a while to cool the car down on a hot day. On other, similarly hot days it cools down much more quickly. Once the interior is cool, it stays that way. The guys at the A/C shop said it probably just needs some refrigerant added, pressure checks, etc. I will be taking it in this fall - when the weather is cooler - to have it serviced. It has never (to my knowledge) been serviced before. They said that it would be a good time to convert from R-12 since the car will be in their shop anyway - I can spend my money adding (expensive) R-12 and having all the old components checked, or just go ahead and have the seals and other associated bits and pieces replaced and the system charged with new R-134. They said they have done refrigerant conversions on lots of "older" cars, the conversion makes the A/C easier (and cheaper) to service in the future (according to them). I can't remember the price they quoted - but it seemed pretty reasonable, considering that they need to replace some parts and seals, etc.

Anyone have experience with this? Your input and advice will be most appreciated. Thanks!!

[amf1932]

I think that this conversion will be cheaper in the long run. I don't know what they're charging for R-12 lately, but you can rest assured that the price will continually go up. ;)

[boRXis]

Yes, you can't live with R12 in future if you want to keep this car for a few more years. I don't know situation in Canada but in my area they used to sell R12 last summer, but I couldn't find it in parts stores this year! They trying to kick out R12 from the market because it damages ozone sphere. Some shops still sell R12 but for extremelly high price - about $100 for can! So, in case if you have a leak in AC system, is gonna be a problem to feel it up!

Anyway I wouldn't suggest you "just swith" if your AC blows cold - put thermometer in the dash air outlet if it from 40 to 60F - you fine, still anough freon in the system, but if its warmer - mos likely you have a leak.

Good luck!

[tds]

I had this conversion done on my 91 LS400 and the A/C works very well. The fittings are a different size so that after the conversion you cannot charge with R12. Note that R134 molecules have a much smaller size than R12. This means that if there are any tiny holes that R12 cannot fit through, R134 may be able to leak through there.

I suggest you pay the extra $100 and have them add a can of stop leak. This stuff will seal any of the very tiny holes that may cause the R134 to leak out.

I suggest you should go fit it :)

[bdonkersgoed]

Nobody had mentioned anything about price . . . how much does a conversion like this cost?

I had my a/c refilled about 1.5 months ago and it only cost me $40CAN ($30US). At first, it was extremely cold, but in the last few really hot and humid days we have had, it isn't blowing very cold (a little cold, but not really cold like it should be) :( I guess I probably have a leak :(

Regards,

Bryan

[tckcumming]

Nobody had mentioned anything about price . . . how much does a conversion like this cost?

I'll look for the estimate I got from the A/C shop & post the price when I find it. I remember that it struck me as quite reasonable, very "do-able" as an alternative to patching up the system and refilling with R-12.

Thanks to all for the comments, especially nice to hear from fellow owners who have made a similar modification. I have a few upcoming maintenance "issues" that I plan to tackle myself, I'll be looking for more advice for sure. I'll also post my experiences here for others to read, if they're interested.

Tim...

[bdonkersgoed]

Thanks for looking up the quote . . . I might be interested in getting this done too.

Regards,

Bryan

[markman]

I'm not sure if yours is like my '98, but I noticed my AC was varying a great deal from day to day. Out of curiosity, I hit the AC button and turned it off. It got hot! So the AC was fighting the heating system.

Then I got to looking and found that the heating is controlled with a water valve just inside the engine compartment (air always passes through the heater core). There is a cable that drives it that comes through the firewall from somewhere inside the passenger compartment. It turned out that the valve wasn't closing all the way, even when the controls were set for "COLD". I popped a clip loose and adjusted the outter part of the cable out a smidge further. That helped, but there was a hint of heat. A couple days later I sprayed a little cleaner and lube on it. That totally fixed it. Now when the control is set to cold and the compressor is off, there is no heat. The AC really cools now.

I don't know if that might be part of your problem, but I'd check it out first. I know a few years ago I heard lots of horror stories about those R-12 conversions. Let's just say get a warranty for the whole system if you get it done!

[monarch]

tckcumming, your AC shop is feeding you the same misinformation that they have fed millions of others in the name of shop profits. The truth is:

1. It's perfectly normal for an R12 system to lose about 25% of its refrigerant charge over an 11 year period due to normal seepage through hoses and fittings. So to restore the factory original cooling performance, all that is needed is to hook up a can of R12 and dispense 1/2 to 3/4 of a can of R12 into the system to "top it off". How much does a can cost? A piddly $20 on ebay. The charging hose is also available on ebay for a piddly $7.

2. Your system does not need any special "checks"and "inspections". The only maintenance it needs is for you, the owner, to try and run the system at least once every week or two THROUGHOUT the year to keep internal parts and seals lubricated. This prevents excessive component wear and prevents refrigerant leaks from developing over time. Also check the AC condenser in front of the radiator to see if it's plugged with bugs, dust and leaves. If so, wash away the debris with a garden hose. If real dirty, remove the radiator to provide much better access to the AC condenser.

3. For 11 years the AC industry has been feeding the public 100% bull about R12 being outrageously expensive and increasingly hard to get. The truth is tons of R12 has been and always will be available on ebay for a cheap price and the prices have been slowly but surely been coming DOWN in recent years. This is because fewer and fewer cars on the road need R12 so the supply is getting AHEAD of demand, especially in winter. R12 sells for as little as $10 a can in winter on ebay. And the capacity of even a totally empty ES300 system is only 2 1/2 cans.

4. R12 systems are the most reliable and durable in the world. Converted systems are much less reliable and durable. Example: The 30 year old R12 system in my antique 1974 Toyota Corona is still running great: http://www.saber.net/~monarch/4m.jpg. Converted systems typically break down in one way or another after only 6 months to 3 years.

5. R12 systems cool better than R12 systems that have been converted to R134a. Example: my LS400 R12 system puts out frigid 32 degree air on its coldest setting: http://www.saber.net/~monarch/accold.jpg Converted systems typically put out only 45-50 degree air.

6. No special license is needed to buy R12 on ebay. Ebay sellers can legally sell it to you if you simply provide them with a letter than says the following:

Certification of Resale

I hereby certify that the containers of Freon12 that I am purchasing from __________ are being purchased solely for the purchase of reselling them. I certify that I will comply with all applicable local, state, and federal regulations and laws and that I am legally permitted to purchase accept delivery of, possess and resell these containers of Freon 12.

My name is_________________________

Adress:

_______________________________

_______________________________

_______________________________

Signed:_________________________ Date:_________________________________

So a conversion to R134a doesn't represent "an upgrade" as the AC industry would have you believe. It's an upgrade only for their pocketbooks. Consumer Digest magazine originally alerted me to this AC industry propaganda back in 1998 and further explained how easy it is for owners to top off their own systems for hardly any cost.

[LEXIE]

tck--

i agree with monarch... do not convert to 134. find you a can of r12 somewhereand add about half as suggested. use your a/c for a couple of weeks to get a good feel for any improvements in efficiency. if necessary, add the remaining.

i had 10 years on my sc400 (r12) before it needed a top off. i would recommend you NOTadd stopleak. your leak, if any, is probably micro in nature and it could be another 10 yrs before another recharge is needed. don't junk your system up with additives.

lexie