Dwahle

I need some help. My A/C needs to be re-charged and I am thinking about converting it from R12 to R134. They sell kits at the local auto parts store.......is it as simple as purging the A/C of the R12, insert new oil and recharge with the R134? One guy at the auto part store says it is, while the other says you have to replace the orffice, seals, etc.? Who is right? Also I read that some AC compressors can't handle the increase of pressure due to R134?

Any help would be appreciated.

BTW, I have an 85' Mazda RX-7 GSL

Rx-7Doctor

iTrader: (13)

Instead of going into great detail. Do a search using the word r134a. We did a very comprehensive thread last year on this that covered everything. If you can't find it post up and I'll see if I can.

Rx-7Doctor

iTrader: (13)

This should be the one.

https://www.rx7club.com/1st-generation-specific-1979-1985-18/fixing-c-634614/

Dwahle

thanks for your help.

Any opinion on alternative refrigerant "Hot Shot"?

Rx-7Doctor

iTrader: (13)

Yes, don't use it. Never had any luck with those type of products.

84stock

iTrader: (5)

Duracool is a driect replacement for R12. There is a distributor here who has great success with it. I've used it in 2 vehicles with no issues. http://www.duracool.com/

Rx-7Doctor

iTrader: (13)

The only problem I have with these alternative refrigerents is that they are here today and gone tomorrow.
Going to R134a which has been around a very long time now assures you that you will be able to find some when you want it.

My advice to anyone on refrigerent. Whatever you decide to go with besides the out dated R12. Buy extra. It will go up in price alot over time and it's good to have some on hand when it is time to service another vehicle or if your present one is in need of some replenishment.
I bought 12 cans of R134a about a year and a half ago for less than $3 a can. Now the cheapest I have seen it is at around $7 a can.

XLR8

iTrader: (52)

Very thrifty Doc.......

You old guys....lol

84stock

iTrader: (5)

Duracool haqs been around for years, it was the first substitute for r12

dantheman

iTrader: (4)

heh, I did the same thing. Bought a entire case for 3 a can. It is over 5 around here now. Since 2 cans will FILL a 7, I shouldn't run out in the near future. Best time to buy it is in the winter though.

wankelbolt

iTrader: (8)

Duracool and a couple other alternative refrigerants have been around for more than a decade, and there is no reason to believe they will disappear anytime soon. They just work too well to go away. Lower head pressures (longer compressor life), lower boiling point (better cooling), simple blends (leaks don't require complete evacuation before refill), non-toxic (won't kill you), near-zero environmental impact (won't kill your descendants), and relatively cheap (won't kill your wallet).

In fact, due to it's environmental impact, R-134a will likely be banned from consumer sale within the next few years, and outlawed completely in another ten or so. If you want a refrigerant you know will be around in a few years, R-134a ain't it. Future automotive A/C's will likely be *very* high pressure CO2.

The other thread mentions that R-134a requires an oil change, maybe an o-ring change, and that it's less efficient at cooling, but it doesn't mention a couple of changes that can be made if you don't have any choice but R-134a. The RX-7's A/C was on the small side to begin with IMHO, so upgrades will be needed to keep your cool.

Replace the condenser with a larger one. Not sure where to get a larger one, but this will have a significant impact on cooling capacity. Also replacing the mechanical fan with a high-volume electric wired to be always-on when the A/C is on will help. Lastly, replacing the factory fixed orifice valve with a variable orifice valve (like SMART VOV) will improve performance regardless of refrigerant.

Good Luck. Sucks to sweat it out in stop-and-go traffic, I know...

Stevan

iTrader: (17)

Duracool is also flamable, it is propane and isobutane.

A parallel flow condenser is what you want if changing to 134a.
You can buy one here: http://www.ackits.com/merchant.mvc?S..._Code=Parallel

Here is my recent installation,

dantheman

iTrader: (4)

Let us know if it works out well!

I did my conversion several months ago before it got too hot. It works pretty good, but not as good as my crx that I converted for some reason.

wankelbolt

iTrader: (8)

So is gasoline, oil, and even antifreeze.

Good stuff. And nicely done.

speedracer_not

I converted to the R134a. Just had to change the intake fittings. Working with it is messy so have soapy water to wash the r134a off the car. Do it in an open area. Wear rubber or latex gloves, and glasses. That **** is messy to work with. And pick a hot day to do it on.

Stevan

iTrader: (17)

Yeah, I just beat the heat too, it's working fairly well (better than before). I'm using r-12, but have not yet had my windows tinted, or set my e-fan to work on the higher speed with the ac on.

jfachner72

I am doing the conversion this weekend.

My parts department has 20lbs of R12 left @ $3.00 an ounce (F THAT)
or
R134a @ .02 c per ounce.......

I will give details next week after I evacuate and recharge the system.

Jason

BARF1

Just stay away from anything with stop leak, that stuff gums up the works.