Window Air Conditioner Leak

thanks for the responses/info .  It does make sense the refrigerant is low as I have had this unit for YEARS.  It is a well made unit by Carrier, but unfortunately they stop making them a long time ago.   I don't have a manual and don't want to risk trying to top it off myself.   I might have to take my chance with getting a portable unit.

Thanks again

Thanks for the update and good luck with a portable unit.

Thanks for the points.

The rest of the story is that if the refrigerant is low then how did it escape? AC units use aluminum for the fan coils and refrigerant loop. Over time, the aluminum gets pitted and eventually porous allowing the refrigerant to leak out a few molecules at a time. It's not something that can be repaired. Topping it off could very well be just a temporary fix.

I did contact a repair company regarding having this done,  as I am not sure if there is a valve so I can do it myself.   Anyway it is way too expensive, given it might not work. And the process to 'super seal it' would cost me another $200.  The refrigerant and adding a valve would cost even more than that.   Next summer,  I might have to purchase a portable unit, although I am reluctant as I have read they don't really work.

I realize this is closed, but there's some misinformation here that could cause others to destroy their window unit.

Note I've put on my "HVAC Contractor for 25+ years" hat, and not my programmer's hat :)

If a window unit is low on refrigerant, throw it away and buy a new one. They hold very, very little refrigerant (1.5 lbs or less in most cases), so ANY loss will cause the unit to malfunction, and you're back to square one (with a few less dollars in your pocket). Very few modern window units are made to be repaired economically, especially in regard to refrigerant issues. Very, very few of them even have service ports where you can connect a hose to the system, and installing one of those tap-on valves is just another place for it to leak. Just throw it away ...

And while older units do tend to leak more than newer ones, age itself is no indicator of "leakiness". I've seen plenty of very old system that are as tight as the day they were put into service. More important is how the unit is constructed (and if it's a Carrier unit, it's probably pretty well constructed), the environment it's working in, and whether it was maintained.

Window units use both aluminum and copper coils. Copper coils can be field-repaired but it's not generally a good idea in a window a/c. Aluminum coils cannot be field-repaired. If you have a leaking coil, having a new coil installed almost always costs more than the cost of a new unit. Just throw it away ...

Some window units actually trap water and use a "slinger" type of system to throw it out to the compressor and coils, so water standing in the coil section is not a definite sign of low refrigerant. This helps the compressor to stay cool, and can lower the temperatures/pressures on the system, resulting in better cooling. Drilling a hole to relieve that water could be the worst thing you can do - but, again, that depends on the type of system you have. The only way to determine if you have a low refrigerant condition is to check the pressures - and as mentioned above you often cannot even do that.

You cannot use refrigerant from automotive stores to charge residential A/C equipment (that's R134A, and window units use either R22 for older ones, or R410A for newer ones). Mixing refrigerants is a sure-fire way to kill that little rotary compressor in just a few minutes, and overcharging is just as bad as undercharging. The "kits" you buy at Home Depot, Lowes, etc are NOT safe to use in window units, regardless of what the box says. They are NOT R22 (you cannot buy R22 unless you possess a valid EPA card) but instead are some sort of blend that is supposed to be safe to mix with R22. It may be "safe", meaning it won't destroy the system, but it won't work, especially in those very low capacity systems. All you'll do is waste a good bit of time, be several dollars poorer, and still hot :)

By the way, when I say "throw it away", I don't mean chunk it in the trash. Take it to a local junkyard that can handle the refrigerant removal (if needed), otherwise you could find yourself on the receiving end of a hefty fine.

i appreciate the info, but as I stated in my question I can not replace the unit.  They do not make low profile units anymore (it's 9 inches high, at most) and a regular sized window unit will not fit.   I would never mess with this myself,  I was considering two options if I couldn't get it working myself:
1.     hire a licensed AC repair company to look at it and give me a quote;
2.   purchase a portable air conditioner (which I am very reluctant to do given the poor reviews I have read).

I am a renter so replacing the window is out of the question.

Thanks again.

i appreciate the info, but as I stated in my question I can not replace the unit.

Then you're left with hiring a repair company to resolve the issue for you. Most of them, however, will tell you the same thing - throw it away.

Most of the portable units I've seen seem to work okay. Their biggest issue is the removal of heat from the condensing section, of course. There's just no way to get all of that heat out of the living space. Also, unless you can connect it to a drain system you're going to have to empty the condensate bucket regularly, which is a pain. All in all, the portables are good for "emergency" cooling while your main system is being repaired, but I wouldn't suggest them for permanent solutions.

I did find several units in the 12" range of height. Any chance those would work?

The 12" will not fit I already tried that size before getting the low profile.
I am still unclear about the portable unit based on what you mentioned.  You indicate they seem to work ok, but then mention they are more for emergency cooling purposes - which is what i have read on other reviews and makes me reluctant to purchase.

I consider a "permanent" A/C solution one that is "set and forget" - like a central unit, or a window a/c unit. Anything that requires you to manage or maintain it daily, like a portable unit, would not be considered a permanent solution, at least in my mind. If you can connect the portable unit to a drain, then it would perhaps be considered more permanent, but it's still not constructed in such a way that you will get years of reliable service from it. You're still stuck with the heat issue, however, and there's nothing you can really do about that.

Our industry does have very heavy duty portable units, but those are cost-prohibitive (and big, and noisy). I am not including those in my suggestions, of course. I'm referring to the ones you'd buy at any big-box retailer off the shelf.

At best, I'd think you would get 2 -4 years of continuous service from one of those units. Of course, this is based entirely on my very simplistic review of those models, and looking at a handful of them for friends and family members. We don't work on them, since they're not really serviceable. They are built to augment your central system, and not be your sole source of air conditioning.

I think you're back to square one for this one - get a service company to repair the unit. Or talk to your landlord about enlarging the window so you could add a more standards-compliant unit to the dwelling (or have them install it, which would be even better).

update from 6 years later! my low profile Carrier Visionaire Window Air Conditioner still works!
I figured out from another site, that when I shut it off when it gets too cold, and then restarting the unit that was part of the problem.  I wasn't waiting long enough to restart the unit (so it was freezing up inside).  It does not work nearly as good as it used too, but it does the job on very hot days to keep me from burning up. I also did install a drip pan underneath (my concern was it dripping near an electric outlet).  The standard drip pan would not fit, so I bought a washing machine drip pan and cut holes on the area of the pan (outside the window). I also did buy a Portable air conditioner that does the job most of the time (until it hits over 90 degrees F with high humidity and then it is useless). so I will use the window unit in those conditions. As I mentioned in the above post, I cannot install a central air conditioner, a standard size AC unit will not work. There is another low profile ac unit that has come out in recent years, but it is very expensive and it gets mixed reviews for doing the job. 

Thanks for updating this question! Glad you found a way around the issue, and good luck!