Help Please! Vac Oil In New AC System

Moderators: Nacho, Tom Greenleaf, ACProf, acsource

Help Please! Vac Oil In New AC System

Postby Davo in Australia » Wed Aug 24, 2016 4:41 pm

I just posted this on another forum and thought it was worth a try here - this is a just a cut-and-paste because it's very late over here. Any help would really be appreciated.

I just put together a brand-new AC in a car and was pulling a vacuum when I was distracted by the kids running around. What a big mistake. I didn't turn off the valves before I turned off the vacuum pump and by the time I noticed the oil level in the pump had dropped and there was oil in the gauge manifold sight glass and in the blue and red hoses.

Searching around the Internet makes it sound like the entire system has to be cleaned, compressor out and drained, the whole bit. What have I done?????
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Tom Greenleaf » Wed Aug 24, 2016 4:50 pm

Welcome:

Wow - are you saying oil from a vacuum pump ended up into the vehicle's A/C system? Sounds like you are. Oh my - Never heard of that happening but if that's correct of course you need a new or good vacuum pump as it shouldn't be able to do that but no way even if that oil was exactly correct and can't imagine it is at all it means clean it all out and start from everything possible known flushed clean, new exact amount of correct oil and charge to spec and probably OK if you haven't tried to run the system yet in the vehicle.

For compressor itself you should probably take it off and spin plenty of oil thru it of the right type as the flush for that not a solvent,

T
MetroWest, Boston
Image
______________________________
User avatar
Tom Greenleaf
 
Posts: 4549
Joined: Tue Jun 28, 2005 8:40 am
Location: Marlborough, MA. USA
Favorite Refrigerant: R-12+134a

Re: Help Please! Vac Oil In New AC System

Postby Davo in Australia » Thu Aug 25, 2016 1:46 am

Hi Tom. Thanks for replying. Yes, that's right, dopey here didn't concentrate and turned off the vacuum pump and not the gauge valves. The healthy vacuum in the system then pulled the vacuum pump oil into the system. I might be lucky if the oil only went into the lower parts of the system, but I'll have to pull it apart and clean a fair bit of it. What solvent should I use? Is compressed air clean enough to blow the hoses out after?
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Tom Greenleaf » Thu Aug 25, 2016 11:19 am

Can't say as it's never happened to me or at this site before.

Guess I'd just treat it like a total flush out job not knowing why oil was in vacuum pump.

Your call now on A/C flush kits or types of solvents. Maybe test some on any remaining oil that it works? Air alone probably not good enough unfortunately,

Tom
MetroWest, Boston
Image
______________________________
User avatar
Tom Greenleaf
 
Posts: 4549
Joined: Tue Jun 28, 2005 8:40 am
Location: Marlborough, MA. USA
Favorite Refrigerant: R-12+134a

Re: Help Please! Vac Oil In New AC System

Postby Davo in Australia » Thu Aug 25, 2016 1:26 pm

It's the kind of vacuum pump that has oil in it with a sight glass on one end. That's what was sucked in and as it's apparently mineral-based it's got to go. At least today I pulled some hoses off and found that only two are affected, and not the compressor or anything else, thankfully. It sounds like using methylated spirits, (which is denatured alcohol to you guys), is the way to go with lots of compressed air to finish off. Or I'll spend more money and make two new hoses. I'll get away very lightly if I only have to do that and replace the drier as well.

This doesn't appear to be a common problem, (probably because a lot of people know what they're doing), and I only found a few threads about it when I did a few searches.
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Tom Greenleaf » Thu Aug 25, 2016 2:25 pm

My "Dayton" vacuum pump is like that type I think. When running a glass shows proper oil level.

One thing I don't get is people leave pumps on long after full vacuum is achieved? I can't understand how if there's ZERO gasses of any type (oils stay) what more you are getting out leaving one on?

Letting it set with gauges on shows it can hold. If not I'll check hoses and try again and see if that holds. If not - find where it's leaking.

I've never lost oil out of my pump? Worked alone so don't know if this happens that much as you described?

There will always be something we can't know for sure. Mineral oils are NOT compatible with PAG oils - that we know.

Never tried in a system other than OE spec oil. Pumps are pumps either vacuum or compressed air I've use synthetic which for a lifetime now with not that much use where I am lasts and can tell the motors working less hard at start up especially.

I have to let you use your judgement on how far to go with what happened as I just don't know of this happening before.

With A/C if you don't know now hope you don't find out that when something is very wrong it harms lots more things than what you may think and gets costly and time consuming both.

Wish you luck,

Tom
MetroWest, Boston
Image
______________________________
User avatar
Tom Greenleaf
 
Posts: 4549
Joined: Tue Jun 28, 2005 8:40 am
Location: Marlborough, MA. USA
Favorite Refrigerant: R-12+134a

Re: Help Please! Vac Oil In New AC System

Postby cornbinder89 » Thu Aug 25, 2016 4:09 pm

Tom the reason people leave it on is because water will not boil until 100 deg F at 28" of vacuum, so a very slight rise on a "wet" system and you will leave moisture in it. The rise from 29" to 28" is small enough that it can be hard to see on a compound gauge. Leaving the pump on for 20 min or so assures that any moisture that vaporized is pulled from the system. Not an issue on a "dry" system, but could be on a "wet" one.
Unless you are useing a real high vacuum pump, most can not achieve a "full vacuum" 28.5" to 28.8" is about all you can expect from a rotary vane pump.
cornbinder89
 
Posts: 212
Joined: Sun Mar 22, 2015 9:10 pm
Location: Lyman, IA
Favorite Refrigerant: R134a

Re: Help Please! Vac Oil In New AC System

Postby Davo in Australia » Thu Aug 25, 2016 4:27 pm

Thanks, Tom. This system has the charge ports pretty low down so gravity appears to have settled the oil only in the hoses, instead of what probably would have happened if the ports were higher up. If that had been the case, then the oil would have flowed down into all the expensive bits. Of course, now my gauge set is full of oil too! Tomorrow will see lots of cleaning and I'll go from there. The rotten thing is that this was a perfect, brand-new system and would have been charged now if I hadn't mucked it up. I think it will be fine but time will tell.

The other stories I found during searches included one where a guy set everything up and went off somewhere, only to find that the pump had stopped working. Someone else had a non-return valve, (which some of these pumps have - too bad mine didn't), stopped working as well.

In case you're interested, here you go:
http://www.refrigeration-engineer.com/forums/archive/index.php/t-13148.html
http://hvac-talk.com/vbb/showthread.php?175097-Help-Vacuum-pump-oil-sucked-into-system
http://acsource.net/acforum/viewtopic.php?f=1&t=8237
http://www.autoacforum.com/messageview.cfm?catid=2&threadid=28811
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Davo in Australia » Sat Aug 27, 2016 10:41 am

Nothing will clean out this oil during experiments, so I think I'll have to make some new hoses instead. At least it's a only a few feet of them. I'll have to get a new gauge set too as I can't get the oil out of them and I don't want it going into the system when charging it.
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Tom Greenleaf » Sat Aug 27, 2016 11:47 am

Wish you luck. Said it's never happened so can't really know.

Solvents: Lacquer thinner (hardware stores etc.) like the stuff to clean painting tools and assorted things should remove about any oily something. But it's so strong may also wreck otherwise tolerant rubber items so can't know. That then must be totally cleared out or risk equipment again AND the A/C system you are working on! Yikes!

Sorry the whole thing happened to you. It shouldn't have and no clue why?

Tom
MetroWest, Boston
Image
______________________________
User avatar
Tom Greenleaf
 
Posts: 4549
Joined: Tue Jun 28, 2005 8:40 am
Location: Marlborough, MA. USA
Favorite Refrigerant: R-12+134a

Re: Help Please! Vac Oil In New AC System

Postby Davo in Australia » Sat Aug 27, 2016 1:40 pm

Thank you, Tom. I've tried quite a few things but anything that will work on a mineral-based vacuum pump oil would be too hard on the hoses. They're neoprene inside and don't tolerant oils and solvents well. I could try it, but it's too risky to possibly contaminate the system. So really, replacement is the only smart option. I made my own hoses so it's just a matter of getting more parts from somewhere.

My gauge set is another matter and I think it will have to be replaced, otherwise there is the risk of the oil going into the aircon with the gas when charging.

The whole mess only happened because I wasn't paying enough attention and turned off the vacuum pump before turning off the manifold valves.
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Tom Greenleaf » Sat Aug 27, 2016 2:16 pm

I hear you. There are such strong solvents they'll dissolve Neoprene, dried paint never mind calibrated gauges and hoses.

A solvent that would remove it is out there but the damage unknown like you already know unknown.

I can't say if the system will or wont tolerate some oil from the vacuum pump and just be fine or not?

The pump shouldn't have let oil out to begin with but that's history now.

The one thing I find hard to clean off or dissolve is Silicone products - sprays or greases. I use both for assorted things not just A/C anything as it about 100% doesn't break down in water. Cleaning just off hands is a pest.

So no perfect known product I know of would bail you out and if there is one someone might know, I just don't.

You may just have to try and hope the rest of A/C oil you use get along with any remaining oil and works. It might?

Tom
MetroWest, Boston
Image
______________________________
User avatar
Tom Greenleaf
 
Posts: 4549
Joined: Tue Jun 28, 2005 8:40 am
Location: Marlborough, MA. USA
Favorite Refrigerant: R-12+134a

Re: Help Please! Vac Oil In New AC System

Postby Davo in Australia » Sat Aug 27, 2016 4:45 pm

Well, I spent a good deal of today learning that Galaxy hose is basically neoprene on the inside, which doesn't tolerate any solvent too well, and finally I discovered the only solvent that will remove the pump oil is naphtha. So while it would do the job, aircon being a bit sensitive to these things I won't chance it and will make some new hoses.

The big problem is that vacuum pump oil in mineral-based and not compatible with compressor oil, so there's no point in risking it.

At least in the last few days I learned a lot. :oops:
Davo in Australia
 
Posts: 7
Joined: Wed Aug 24, 2016 4:37 pm
Favorite Refrigerant: 134a

Re: Help Please! Vac Oil In New AC System

Postby Tom Greenleaf » Sat Aug 27, 2016 6:04 pm

Finding out WHAT DOESN'T WORK IS WINNING! If before you wreck something.

BTW - Neoprene spelled with a capital letter means it's brand name and is by Dupont. We know it as rubber that is tolerant to fuel and oil and hose should be marked with a rating or spelled out. So is Freon in lower case just means "refrigerant" - just points of small importance.

Naphtha was/is a petroleum product known to be easily flammable and leave zero odor when evaporated used for ages in wick type lighters as the fuel. Now using a cheaper product marked "light petroleum distillate" just read a container! It's all made from a fossil fuel but characterizes will be all different.

Back to the game. If some mineral remains it was once told to me in person on the phone ''INTERDYNAMICS USA" that Ester oil was a refrigerant oil that would be compatible with mineral oil for use with 134a refrigerant such that any left when converting cars was so popular they didn't need to worry too much - it made the two work together and flow with the refrigerant to lube your compressor is what you must have going on.

They probably aren't happy with me because they also were the leader in selling what we call death kits and magic sealers that can really ruin a system and just don't admit it or care!

Now you'll know better than I could what matches in Australia by names, name brands better than I could.

I'd think about (get a second opinion) putting a couple oz. of Ester oil in this job and cross my fingers! I'm really not sure on that either so AYOR if you try a trick.

Other is just blow out what you can, fix anything known messed up and go for it. If it really wrecked or reacted I think it would fail early on you - a total bummer.

My point is what can make two different oils join each other and work together. Both are lubricants for a pumping device - vacuum pump or compressor pump need their lube.

Said before. I just have no case known before with this and what was done to get out of it so learning right along with you,

Tom
MetroWest, Boston
Image
______________________________
User avatar
Tom Greenleaf
 
Posts: 4549
Joined: Tue Jun 28, 2005 8:40 am
Location: Marlborough, MA. USA
Favorite Refrigerant: R-12+134a


Return to A/C Questions and Opinions

Who is online

Users browsing this forum: Bing [Bot] and 5 guests

cron