Ok, I did go to school yearsa ago at a HVAC school but I never really got much out of it besides some good electrical exp. and some cool friends but anyways, can you drop 134A into a fridge that has leasked out all of its' R12? I've been told that you can and told that you can't. I also was told that back in the 90's that most of the places that advertised to retrofit your car from R12 to 134A was mostly scams. But I have a dorm size fridge that came with R12 and someone had sweated in a valve to refill it so I assume that all the R12 has leaked from the valve. I don't suspect any moisture to have made it's way into the system. So why can't I re-charge with 134A?
134A & R12 Question~
- Thread starter xyz
- Start date
Help Support :
exploder3211
Well-known member
- Joined
- Dec 24, 2006
- Messages
- 1,664
If you lived closer i'd give ya the one off my porch
But they cost around $50 or so for a new one.. I always thought you couldn't.. But then i am not always right... So..
But they cost around $50 or so for a new one.. I always thought you couldn't.. But then i am not always right... So..
captainmoody
Well-known member
- Joined
- May 22, 2006
- Messages
- 348
134A uses a different oil than R-12. I would just find some R-12 on ebay and be done with it.
There are drop in replacements for R12 that I use successfully. One is called Hot Shot.
kennyGF
kennyGF
58limited
Well-known member
I have been using Freeze 12 in my cars and my 1950 GE fridge - you can put it right in with R-12 if any is left in the system, and it is capable of getting very cold.
I have been told by some that you have to have a license for it, and others say you don't. My local auto parts store sells it to me with out a license.
I have been told that it has some propane in it, so don't smoke when using it.
I have been told by some that you have to have a license for it, and others say you don't. My local auto parts store sells it to me with out a license.
I have been told that it has some propane in it, so don't smoke when using it.
R134 can be retrofitted to most automobiles, and I imagine most refrigerators will follow the same upgrade path. The problem with R134 is that it will not circulate the mineral oil that is used to lubricate the system when it used R12. Because of this, two new synthetic oils were developed...PAG and Ester oils that will circulate with R134. The problem is that for best performance, you gotta get all the old mineral oil out of the system. In an automobile, this can be relatively easy in some cars because the system disassembles easily by detaching all the hoses, but can sometimes be hard because cars can have refrigeration parts installed in some obscure places. There are chemicals avaliable at most HVAC supply shops that resembles brake part cleaners that will flush out all the old oil.
Once all the old mineral oil is out, you can start putting the new oil back in. Now, first a few things about the new oils... They are hydroscopic, meaning, they will absorb water. Water and air conditioners don't work well together. It will freeze in the lines and the system will quit working when the refrigerant cannot flow. The best way to add oil is to buy it in combination with the refrigerant in the pressurized. That way it won't absorb water while it's sitting in the lines waiting for you to re-assemble everything else (no matter how fast you assemble them, it will still suck up moisture) Another thing...make sure you remember what type of oil you installed in the system. When the oils mix, they turn into a nasty gummy mess that is impossible to remove from the system!
Now, for recharging, after flushing out all the old oil and cleaning things out, you will want to vacuum out the system with a vacuum pump. This will also remove moisture because when you lower the pressure, the water will boil off. It is important to get the pressure low enough that the water will boil off at the ambient temperature. Also, in an automobile, they use a receiver/dryer with a dessicant in them. In household refrigerators. I'm not sure if a dessicant can be installed in an appliance or not.
Once the system is vacuumed down for over an hour or so it is good to go for adding the new R134 refrigerant. After you seal it all off, you're ready to run it!
Now, those R134 "retrofit" kits can sometimes be good and bad. Yes, they work, but not all that good. They come with a can of R134, oil charge, a chemical dessicant, and sometimes a leak sealant. Again, the problem is that you need to get out the mineral oil before the system will perform. Most R134 retrofit kits have some sort of chemical neutralizer that just simply makes the old mineral oil settle to the bottom of the coils where it won't cause a poblem. The issue with this is that it now consumes surface area that could be used for heat transfer, thus the unit works less effectively. If you flush the system out, the R134 retrofit kits are great becasue they provide you with everything you need to get a refrigeration system working good again...it's just that there is a bit more involved than just a $50 kit. If you do the labor yourself then there's no more cost, but having a HVAC shop do this, at least in a car, will cost about $200-$300.
Once all the old mineral oil is out, you can start putting the new oil back in. Now, first a few things about the new oils... They are hydroscopic, meaning, they will absorb water. Water and air conditioners don't work well together. It will freeze in the lines and the system will quit working when the refrigerant cannot flow. The best way to add oil is to buy it in combination with the refrigerant in the pressurized. That way it won't absorb water while it's sitting in the lines waiting for you to re-assemble everything else (no matter how fast you assemble them, it will still suck up moisture) Another thing...make sure you remember what type of oil you installed in the system. When the oils mix, they turn into a nasty gummy mess that is impossible to remove from the system!
Now, for recharging, after flushing out all the old oil and cleaning things out, you will want to vacuum out the system with a vacuum pump. This will also remove moisture because when you lower the pressure, the water will boil off. It is important to get the pressure low enough that the water will boil off at the ambient temperature. Also, in an automobile, they use a receiver/dryer with a dessicant in them. In household refrigerators. I'm not sure if a dessicant can be installed in an appliance or not.
Once the system is vacuumed down for over an hour or so it is good to go for adding the new R134 refrigerant. After you seal it all off, you're ready to run it!
Now, those R134 "retrofit" kits can sometimes be good and bad. Yes, they work, but not all that good. They come with a can of R134, oil charge, a chemical dessicant, and sometimes a leak sealant. Again, the problem is that you need to get out the mineral oil before the system will perform. Most R134 retrofit kits have some sort of chemical neutralizer that just simply makes the old mineral oil settle to the bottom of the coils where it won't cause a poblem. The issue with this is that it now consumes surface area that could be used for heat transfer, thus the unit works less effectively. If you flush the system out, the R134 retrofit kits are great becasue they provide you with everything you need to get a refrigeration system working good again...it's just that there is a bit more involved than just a $50 kit. If you do the labor yourself then there's no more cost, but having a HVAC shop do this, at least in a car, will cost about $200-$300.
If someone put a process fitting on the unit, it probably has a leak. Not worth your time to fix it.
Ken
Ken
