I have tried several combinations of the R-12, 134A and propane. The best I can get to work for my cars and trucks is to fill the system about 2/3 to 3/4
with the freon and the rest with propane. Pure propane will get the coldest, but will eventually freeze-up the duct work and stop cooling.

 

I'm running 134 with the cycling switch bulb pulled almost all the way out of the discharge line. Works OK.

 

You should be able to get the high side adapter at most Auto Parts store, they also use them on GM's
Jim

 

I use Hot Shot R-414B and it seems to be legal here in California.
Jim

http://www.icorinternational.com/ind...&products_id=4

 

I guess I'm just lazy.

If and when my mess leaks, I replace the offending O-ring or gasket and refill it with R12. Got a 30# cylinder I bought years ago when it was about $45 IIRC. Gold is cheaper these days.

If you fella's have any refrigeration buddies, ask them about the R12 they remove from systems they're upgrading to R414b or the like. More often than not, we've got a cylinder of reclaimed R12 that just needs to be run through a filter/drier to be good for our purposes. As we can't legally resell it as new, we're bound to turn it in for alleged recycling.


Regarding R414b:, with any 400 series of interim refrigerant, you generally only have to install 80% (by weight) of the original charge.

414b HotShot is good stuff and functions very well as a "Drop-In" replacement for R12 (with standard replacement of the filter/drier).

 

I have been researching and doing some PMing to members here and elsewhere, and have decided to go with DuraCool (propane) when the time comes. I am going to buy a gauge set and already have the adaptor fittings. Going to have g/f's shop flush the system after I replace the drier, expansion valve, and o-rings. (But then if it doesnt leak, I may leave the o-rings alone). I figure I'll come out ahead by buying the tools and doing it myself rather than have the shop recharge with 134A @ $1.50 per ounce, and run the risk of marginal results. Mom's doesnt cool very well on hot humid days. Even on high MaxAC, I still break a sweat in her truck. Plus, I cna fix my buddy's AC, check Mom's.......

Daniel

 

I've been thinking about buying some half decent tools for refrigeration work too.

Where can you buy gauge sets and vacuum pumps at reasonable prices?

JP.

P.S.: I went to Harbor Freight and the first thing on their page is a gauge set for $30. Does any body have one? Work OK?

Thanks,
JP.

 

if one can do the work i would suggest using what one wants to use. otherwise you mite have a problem getting it worked on in a shop because of contaminating the shops equipment.

 

Well heres an update. I tried the A/C on the highway today. Outside air temp was 70 and vent temps were about 38F. Ice cold air. I think it just needed the air flow to help it. I think the electric fan would make a difference if your doing alot of idleing/slower speed to help get the airflow moving across the condenser. especially with anything other than R12. I may look into that.

 

You might want to consider installing an electric fan in front of your condenser like the ones out of a front wheel drive car or almost any Asian import to increase your airflow at low speeds. They have some nice thin and powerful ones that you could mount up front.

Also I have seen that some of the retrofits need to have the condensers replaced while some will WORK ok, the R134a units need a larger condenser that the R-12 did.

 

I thought id add this, if you need a vacuhm pump drop by a place where they work on fridges, a fridge compressor makes a great pump, its 110 and has two tubes coming out, just solder a shrader fitting on it and drop a few drops of oil in it each time, it last for years.

 

. . . . giggle . . . .

HVAC tools, just like any tools are like our trucks. How fast do you want to go?

My daily-driver vacuum pump is $850 to set on the counter. Good for ten CFM free air on down to less than 50 microns. Proper refrigeration practice has one bring it down to between 300 and 500 microns holding it there till all non-condensable gasses and moisture is removed. My pump will pull down an AC system such as ours to less than 1000 microns in less than two minutes (assuming dry and leak free). Longer if the system's wet.

The smaller caliber pumps will take longer to get to that deep a vacuum.

When you get to that point, start the pump and take the wife out to dinner. If your system is clean and tight, you should be in the ball park by the time you get back to it.




This helpful message is brought to you by the letter G.

 

what is this "air conditioning" you guys talk of?

 

It's inside cab refrigeration . . . .
as opposed to 5-80 air . . . .
that's 5 windows open at 80 mph.

 

How you getting *5* windows? Or do you open the club cab vents, too?