Condensation removal....

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The low temp cutout may have different settings, but that is most likely a result of the diferent refrigerants used, r12 vs 134a, Your 83 may still run at 40, but there is a temp close to that where it will no longer engage.
They all had low temp cutouts for the very reason I mentioned. Or, the low temp cutout may have been by-passed or is not working properly. Take it out on a cold frosty morning and run the ac and let us know what happens. I'm a mechanic by trade (inter-provincially licensed) and worked in the field in the 70's and 80's and never saw a compressor cycle in temp below 35 to 40 F. Up here in the frozen north of Canada we use our defrost a lot and they would engage the compressor in the mild weather, but have never seen a compressor run in the cold. Not sure what it has to do with buying a 3 gal toilet tho...
wrote:

the
would
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Has nothing to do with the refrigerant. Has solely to do with the temperature water freezes at ... 32 degrees. Since in most cases, all air flows thru the evaporator and then to or past the heater core, were the water on the evaporator be allowed to freeze solid, no air would flow out of any of the plenum chamber outlets.
--

- Philip

"Steve G" < snipped-for-privacy@Steve-Garner.com> wrote in message
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Philip, We're talking about two different controls. There are sensors, or in older cars, capillary tubes at the evaporators monitoring evap temp to control what you're talking about, evaporator icing. In late model cars that also cycled the compressor as that was how pressure/flow of refrigerant was maintained. But there is also an ambient temp sensor that would not allow the compressor to run below a certain outside air temp in order to prevent hydraulic lock-up of the compressor due to refrigerant being in a liquid state in the comp head. Refrigerant "boils" and becomes vapor at a low temp, that's one of the reason it's used as a refrigerant. If the temp drops below that "boiling point" on the low pressure side the gas will condense back into a liquid and hydraulicly lock up the compressor. I mentioned the diference in the refrigerants as a possible explanation for why the posters old lincoln a/c would run at temps below his late model mustang, however I was simply stating that the American government didn't regulate this 40F cutout, the laws of physics did. Steve.
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Stop. Evaporator icing prevention has been prevented electrically by cycling the compressor since I can recall (late '50's). Evaporator icing prevention has also been prevented mechanically by the use of expansion valves ... LONG before GM's cheap, clog prone capillary tubes ... by regulating refrigerant based on expansion valve temperature.

Late model. LOL

snip
This is false. Evaporator core surface temperature is the primary concern because the freezing of water condensation on the evaporator/s exterior surfaces will block air flow. There is never solid liquid refrigerant condensed in the compressor inlet line, regardless of ambient temperature. Well... there *could* be if the system were grossly overcharged.
--

- Philip


> "Philip" < snipped-for-privacy@earthlink.net> wrote in message
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About a year ago, I did have to replace one of our toilets. Bought a new Kohler. They play all sorts of timing, level, and displacement tricks to limit the flush volume to 1.6 gallons. But after you "change things" and since the tank size permits more water storage, the flush can easily be increased to just under 3 gallons. Want a used 5 gallon flusher? LOL
And you are COMPLETELY in error about buying a top loader washing machine. They dominate by wide margin. Front loaders are the in the small minority of units sold.
--

- Philip


< snipped-for-privacy@mailcity.com> wrote in message
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snipped-for-privacy@mailcity.com wrote:

they still sell top loaders
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wrote:

You have to know that MikeHunt is retired 'gentry' ... who knows little beyond what his house servants relay to him on this subject.
--

- Philip



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Why do you always seem to find it necessary to stoop to personal assaults? Have I ever personally attacked you or anyone in a NG? I would suggest you do some research before you choose to comment on a subject of which you obviously are not fully informed, or at least say in my opinion
One can still buy Freon, as well, but it can not be manufactured. ;)
mike hunt
Philip wrote:

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Mike ... you have always hinted around at your wealth on this and several other forums. Don't even try ... to go humble on me. LOL If you interpreted my comment as a negative, send me a check sufficient to remove that discomfort for being "gentry". ;-)
There are plenty of appliance outlets including Sears that sell NEW top loaders today. And so long as the price of a front loader is relatively high, politics (poor people disproportionately affected) will delay your notion ... or there will be a government subsidy. LOL
--

- Philip

< snipped-for-privacy@mailcity.com> wrote in message
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Can I have a check, too? I could use a new front loader. :)
Aaron

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Thanks. We had that very issue with this car (89 Toyota Corolla). The spare tire well filled with water shortly after we bought the car. It [water] was coming in from the rear lights which were newly installed (without sealant). Fixed that problem.
No AC in this car. So, unfortunately, with where we live (Northwest Oregon) and the amount of rain we get and how cold it is here until, like, next August -- LOL -- we'll just have to deal with it. Floormats are a must in this wet area. SO they're stayin'.
I will try Anti-Fog wipes. Will see how those work out. Rainex works great in this area. I know that much. But that's the outside. And the wipers work fine getting that "condenstation" off the windows.
Aaron
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On Mon, 20 Dec 2004 20:55:36 -0500, snipped-for-privacy@mailcity.com wrote:

^^^^^

Newer != most, top poster.
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Where did *you* read that it's a Federal Regulation about cutting A/C at 40 degrees? And don't give me that "go look it up BS."
--

- Philip

< snipped-for-privacy@mailcity.com> wrote in message
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Gary L. Burnore wrote:

Hah hah. I can't see anything but destruction in my future from doing that... either the system overheats cuz there aren't enough holes, or there are too many holes to keep it warm. I could blow a few units trying to get it right! I can live with it.
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It does apply to automotive A/C.

In fact, A/C systems start cycling the compressor at no less than 38 degrees F. SO... when the air coming into the evaporator reaches this low temperature, the compressor is cycled or shut OFF if the air temperature entering the evaporator continues to drop. Otherwise the evaporator would become a block of ice, which would prevent any air from reaching the heater core (in nearly all cases).
--

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Philip wrote:

Now THIS makes perfect sense. (I'd have to look up the temp at which refrigerants go liquid to confirm or deny Steve G's belief.) I'm almost certain that the A/C on my old 85 Pontiac would cycle at any temp, though. I'll check up with the Honda soon.
Anyway, I doubt it would be that difficult (in the original design) to construct an airflow system that would shunt warmer air around the evap unit when the temp dropped in winter, in order to preserve the dehumidifying characteristics of an A/C-based system.
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degrees
would
heater
You would also have to direct warm air to the entire low pressure side of the ac system to prevent the condensing of refrigerant gas back into liquid. I live in a climate of 10 months of winter and 2 months poor sledding, have been a licensed mechanic since about '72 and have never seen an ac comp cycle in ambient temps colder than somewhere around that 40 degree mark. and remember from my days in tech school that is the reason. Don't forget when researching boiling point of refrigerant to factor in the pressure. Adding pressure also raises the boiling point. As I'm typing this I'm also recalling that there are cautions that when servicing/charging the system to not allow low side pressure to drop too low for fear of damaging the compressor. Go to K-mart and look at the labeling/cans of 134a they market to the consumers and read the instructions. When charging you override the low side cutout so you can keep the compressor running. In this situation, temp above ambient cut-out and low pressure limit overidden, a drop in low side pressure can take it below it's boiling point and risk liquid refrigerant in the compressor. The warning on the charging kit doesn't get into the explanation, but does give the caution about low side pressure drops and damage to the compressor. Steve
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Question for you: Water condensation *on* the evaporator surface freezes at 32F. At what temperature does low pressure refrigerant gas condense to a solid liquid? Keep in mind that it is common to see frost all over much of the exiting line from the evaporator leading to the compressor inlet while the A/C system is functioning normally. Clue: it's lower than 32F.

snip
Not entirely accurate. The compressor's inlet side can drop into a slight vacuum when a suction throttling valve is used on the outlet side of the evaporator instead of an expansion valve to regulate refrigerant flow into the evaporator. In any case, the low side pressure safety switch (if/when there is one installed) will prevent such a condition from occurring on systems equipped with only an expansion valve. Excessive high side pressure is FAR more damaging to compressors which is why a high pressure safety switch is present on all but the oldest automotive systems.
--

- Philip



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Thank you ('perfect sense'). Note that I said "air coming into the evaporator." If air door is set to FRESH and the inducted air from outside is below 38-40F, all one need do (considering all the heat radiating off the passenger(s), is select RECIRCULATE so that the air inducted to the evaporator stays above 38-40F. This will keep the A/C running. Remember ... once the evaporator effectively become a solid block of ice, there will be NO dehumidification.
--

- Philip



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Philip wrote:

Oh, duh! That's a pretty easy solution. I think this answers Steve G, too. Now if we only have a cold day around here on which I'm driving so I can check it out on my Honda... not that I really want a cold day just to check this, of course. ;-)
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