HVAC Work

[Frank]

So I am going to be changing my AC compressor and my HVAC lines... and the dryer and expansion valve. I am going to take this time to change over to ES-12A. It is stated that ES-12A doesn't technically require to be vacuumed down, so I was going to at least plan on putting the ProDry into the system before I mix the ES-12A into it.

It has been a long time since I have done any real AC work. What is the best recommended method for putting oil back into the system and which kind?

Thanks!
Frank

[zin]

If it still had R12, then it's mineral oil... If it had been converted to R134, you'll have to flush it and then clean out all the lines. I'm not sure the compatibility of the ES-12A with the funky lubes 134 used, but I recall it was 100% compatible with mineral oil.

If you are replacing the drier I guess you'll be ok with not pumping it down, assuming the system hasn't been open to air and will be exposed for the short time it takes to replace the parts... BUT, pumping it down is also one of the ways you check for leaks...

You'll have to let me know what you think of ES-12A, I've been pretty well sold on it since I've done some research, just haven't been motivated to do it yet, mostly due to availability of ES-12A. The only place I seem to find it is Ebay...

Mike

[Frank]

I will let you know! I was going to try and do some system flush before hand... but I am porbably just going to air hose the cond and evap out.

http://autorefrigerants.com/co00033.htm

[5sp. mini]

flush before you change dryer it wound be nice to vac. it down to remove any moister.

[RoadWarrior222]

If you've got a filter, oil/water separator, line drier setup on your compressed air system you could blow it out, but otherwise, it's likely to put more crap in there than there was in the first place.

I am using the Duracool R12A system on my Escort. It had sat 2 years, leaked down, and then been run another year, so figured the seals had dried out. Last year put the dryer/lube/sealant/leak tracer kit in it, and it brung it up to operating pressure and worked great last summer, kept working into this year, but I've been having issues lately, which I think are external*. When it blows it's arctic gale cold though. (Kinda annoying since I don't really have a temp control, just a blend control, and I end up manually cycling it on an off, because in 10 mins you're shivering.) Needed one can of refrigerant this year, was dithering whether to add a can after the R&R kit went in last year, since it didn't bring it all the way up.

* found one dud relay, another is suspect and condensor needs R&R because 1/3 of the area is ineffective due to impact damage and debris, which also effectively blankets that part against the vehicle radiator....

Anyhoo, the voyager R12 system has leaked down to nothing over several years, and I'm probably going to use the same kit on it. However, since it's probably completely at atmospheric now, I'll probably hit it with blowtorch and heatgun at every metal bit I can see to drive out moisture and as much air as might be in there.

[turbovanman²]

I would find out what oil the ES12A recommends. When 134A first came out, they said we had to flush out the old oil, but over time, they found out we didn't have too. You could buy a syringe setup, it fits onto the low side port and you put as much oil in as you want. I'll have to research that refrigerant, sounds like a good option.

---------- Post added at 10:53 AM ---------- Previous post was at 10:50 AM ----------

Damn, that's neat stuff, cheap too.

Frank, looking at the FAQ chart, you can use any oil you like-

http://autorefrigerants.com/Envirotechnical.htm

[turbodaytona87]

I run ES-12a in my Ram. Works well, cools to 40* below ambient (which is a good temp range for the Ram setup), and cools down relatively quickly. Plus it has a nice pine scent so you can smell it if your evaporator happens to leak. From what I remember, ES-12a can be used with either type of oil whether it is an r-12 or r134a system.

[Frank]

ES Refrigerants has a ProDry can which will remove any moisture from the system. To save myself the cost of buying a vacuum pump, I am planning the following:

1. Remove my old parts - compressor, lines, dryer, and expansion valve.
2. Use my air hose w/ filter to blow out the evaporator and condenser.
3. Install new parts***
4. Charge with one can of ProDry, run for 30 minutes
5. Bleed of some of the contents
6. Charge w/ ES-12A

When installing the new parts, do I put all 7oz of oil into the compressor that the system specs call out? Also, I believe with the 12A setup, I use the same oil as R-134? The system was converted to R-134 a long time ago, so I am hoping that is the case since I am sure there will be some old R-134 oil still left in the evap and cond.


Thanks!
Frank

[zin]

You don't normally want to dump any kind of liquid into the compressor as it isn't designed for it and will essentially "hydro-lock" breaking it. Most of the oil is in the condenser and so you could add it there, or on the low pressure side, as that slowly adds it to the mix...

Mineral oil is what was used with R12 and is pretty benign to most rubbers, which isn't always the case with the ester and other oils used with 134, but if they had been replaced as part of the conversion they should be fine. If the lines don't look clean and dry (greasy coating on the outside), they are probably due to be replaced as this can indicate the are becoming porous.

Otherwise, sounds like a solid plan to me!

Mike

PS If you go with the oil for the 134, you need to be sure you are using the same type of oil, as they generally don't get along too well, or at least didn't back when they first came out, and different manufactures used different lubes... If in doubt, flush it out!

[Frank]

I am assuming it was properly flushed and converted to R-134 including the oils. So I will use the oil for R-134.

I know what you mean about the lines. I am having to replace them all because the lines are leaking out the oil and dyes in the system.

[turbovanman²]

The condenser and evap core hold a bit, I wouldn't even bother flushing it if nothing blew up, waste of time IMHO, and based on the info, I'd use mineral oil.

Does the new compressor come with oil? If so, I would add maybe 2-3 oz's to the dryer and leave it at that.

[Frank]

I will take a look when I get home at the new compressor. Here is what I was looking at purchasing tomorrow:

http://www.es-refrigerants.com/produ...ue/details.asp
http://www.es-refrigerants.com/produ...it/details.asp

and depending on what I need for oil, http://www.es-refrigerants.com/produ...ue/details.asp

Any concerns?

Thanks,

[turbovanman²]

Looks like you have it covered.

[turbodaytona87]

One thing I've done for a vacuum pump is pull the compressor out of a refrigerator, and use that with an adapter to hook up to my gauges. Also supposedly the ES-12a doesn't care about moisture, and I think they recommend charging at a 0 vacuum/pressure so the low side isn't too low.

[black86glhs]

You don't normally want to dump any kind of liquid into the compressor as it isn't designed for it and will essentially "hydro-lock" breaking it. Most of the oil is in the condenser and so you could add it there, or on the low pressure side, as that slowly adds it to the mix...

Mineral oil is what was used with R12 and is pretty benign to most rubbers, which isn't always the case with the ester and other oils used with 134, but if they had been replaced as part of the conversion they should be fine. If the lines don't look clean and dry (greasy coating on the outside), they are probably due to be replaced as this can indicate the are becoming porous.

Otherwise, sounds like a solid plan to me!

Mike

PS If you go with the oil for the 134, you need to be sure you are using the same type of oil, as they generally don't get along too well, or at least didn't back when they first came out, and different manufactures used different lubes... If in doubt, flush it out!

This isn't really true. The compressors should have oil in them. You have to be careful where you put it. If you add it to the outlet, yeah, your going to stress or break the compressor. Like putting oil in your cylinders then starting the car.

[DodgeZdad]

This is a propane refrigerant and I though it was illegal in the USA, but maybe not for autos. I wish I was closer so I could lend you my vacuum pump though. Air and any kind of refrigerants don't mix and gives you erratic pressure readings.

[zin]

Not illegal as far as I know, in fact, I believe it is used in commercial refer units as it can go lower than some others, and is not as nasty as anhydrous ammonia (R717)...

Funny thing is, in the early days, when refrigeration was new, and gas lighting was prevalent, DuPont marketed Freon as being safer because it wasn't flammable, nevermind that when it was combusted in a fire it produced phosgene, a chemical weapon from WWI. In fact Freon is a Chloromethane (notice the methane part), but was patentable, whereas propane is a naturally occurring substance...

It is also interesting to note that soon after DuPont's patent ran out on Freon, it was "discovered" to be harmful to the ozone layer..., but fear not! DuPont had a patented replacement ready to go... Now that 134a's patent is/has run out, seems it's not so safe either... I wonder what patented wonder chemical they have in store for us?

The fear of flammability is unfounded, though I'm sure if one presented the perfect set of circumstances it could become hazardous, maybe. But then again, what we have to deal with today is toxic from the start, so I would hazard a guess that propane based refrigerants are safer over-all.

Probably WAY more than anyone wanted to know, but there it is!

Mike

[RoadWarrior222]

This is a propane refrigerant and I though it was illegal in the USA, but maybe not for autos. I wish I was closer so I could lend you my vacuum pump though. Air and any kind of refrigerants don't mix and gives you erratic pressure readings.

It's illegal to put it straight into an R12 system without retrofitting the system to R134 first. Dumb.