Need AC operation explained ! ! !

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My wife insists on setting the whole house AC thermostat at 70-72 at night. I've told her that if the outside temperature is 67, the AC won't work correctly. That the outside temperature has to be higher than the temperature you're trying to cool the house to. Can someone state this in an explanation that she will understand?
Also, during the night the circuit breaker that the AC is on has been tripping lately. Could this be because the unit is running for hours without shutting down? Putting a load on it and thus causing the circuit breaker to to trip?
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night.
temperature
She understands everything she needs to, she knows you and knows you are crazy. :-)
Many times the outside temperature is less than the set temperature. One of two things happen. If the inside temperture is less than the set temperture, nothing happens since the thermostate will be happy. If the inside temperature is higher than the set temperature then the AC will start running and dump the excess heat outside. Since it is pumping the heat downhill, it will work less hard and save you money.

tripping
shutting
trip?
If anything running at night when it is cool would be less load on the AC (there are unusual circumstances that this may not be true, but it does not sound like it here). There are a number of possible problems that could cause the breaker to trip, but it sounds more likely that the breaker is going bad and needs to be replaced. Do you run the AC during the day? Does the breaker trip then?
--
Joseph E. Meehan

26 + 6 = 1 It's Irish Math
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She seems to understand . Your house warms up, and gets humid, at night she wants it kept comfortable. Besides cooling the house you are keeping the humidity under control ,which usually rises outside at night. Im not sure of the actual low temp it is damaging to run your ac, but I beleive for some units it is 55 or lower, you wont hurt your ac running it at 65 outside. And it will work fine. If Its hot and humid in the house run your AC . Your breaker problem is different, have a Pro check it out , it could be something serious is happening and should be repaired before more damage occurs
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shut up retardo boi..
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TOM KAN PA wrote:

When the outside temperature gets below 70 the more indoor heat load you get on the evaporator coil the better. This is because when the system heatload becomes too low the pressures drop below freezing on the evaporator coil which results in coil blockage. Which results in possible liquid flooding back to the compressor which can ruin it in no time flat. In lower temperature environments a control is needed to control the condenser blower motor so the condensing temperatures stays within tolerable specifications. The colder it gets in the conditioned space the more dangerous it is for the compressor. They used to have suction line accumulators and low pressure switches to help protect the compressor, which many units don't have these days. These days accumulators are rare on A/C units, --but they are critical for protecting Heat Pumps and therefore are installed on them. Where nights get cold strap on crankcase heaters are essential to keep refrigerant from condensing into the compressor's oil which leads to slugging and oil where it shouldn't be in the sealed system. Along with premature compressor failures.
--
Air Conditioning System Sizing for Optimal Efficiency -
http://www.udarrell.com/airconditioning-sizing.html
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tripping
shutting
trip?
That's an explanation she's sure to understand! :-)
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Oh, gosh, let me count the ways. More inserted.
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Christopher A. Young
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Stormin Normin . My portable room dehumidifier and most , will freeze up below 60f. My refrigerator Kenmore , New , states not to operate it in room temperatures below 50 or 55 , { I forget } Im sure similar principles apply to central AC , One unit I have has a heater built in , and another of same brand I was told doesnt, both are Lennox. My installer said dont operate my AC below 55.
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And all of your comments are quite irrelevant to what I said. Oh, well.
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Christopher A. Young
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Im no HVAC Pro , but what I beleive is missing here, in this thread is . ? Many exterior Ac condensor units are different as to its design and encompasing operating parameters or tollerances for operating temperatures. Within a given range of ? degrees ? But All are within an apx 15 degree range of one another . And All are unique as to low operating temp , for resideniial units. This is around 54 to 58 degrees ???? Refrigerators , are different my Sears says 50 to 55 minumum .. My dehumidifer says 60 before freeze up and defrost cycle I am learning
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And you cant answer what he asked?
Oh..btw....you ARE keeping up with the thread you started in AHVAC are you not?
Look..when you want to be bought out, let one of us know.

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Hi Stormin, hope you are having a nice day
On 18-Aug-03 At About 01:30:01, Stormin Mormon wrote to All Subject: Re: Need AC operation explained ! ! !
SM> Oh, gosh, let me count the ways. More inserted.
SM> --
SM> Christopher A. Young Learn more about Jesus www.lds.org SM> www.mormons.org .. ..
SM>
>> > > When the outside temperature gets below 70 the more indoor heat >> load you get on the evaporator coil the better. This is because when >> the system heatload becomes too low the pressures drop below >> freezing on the evaporator coil which results in coil blockage. Which >> results in possible liquid flooding back to the compressor which >> can ruin it in no time flat.
SM> CY: And what does freezing evap have to do with the outdoor temp?
because the low outdoor ambient lowers the head pressure too much
>> In lower temperature environments a control is needed to control the >> condenser blower motor so the condensing temperatures stays within >> tolerable specifications.
SM> CY: Huh? Not heard of this.
You really need more field experience there son.
-=> HvacTech2 <=-
.. Sure I can help you out, which way did you come in?
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On 15 Aug 2003 13:09:04 GMT, snipped-for-privacy@aol.comic (TOM KAN PA) wrote:

    Sure. I'll explain it to her.
    First, however, you explain to me how the outside temperature has anything to do with the air conditioner.
    The air conditioner is controlled by the thermostat. The thermostat measures the inside temperature.
    It does not matter of the outside temperature is 100 degrees or zero degrees. If the inside temperature is higher than what the thermostat is set for, the air conditioner turns on. The thermostat has no contact with the outside temperature. It cannot know what the outside temperature is. What's more, it doesn't care. It is only concerned with the inside temperature. That's its job. It's very single-minded about it, very focused. It has no imagination.
    Perhaps your air conditioner has something on it that measures the outside temperature for some reason. This is not impossible. I have just never seen one nor could I fantom why it would. If it does, I want to go out and find one just like yours so that I can learn something new. Look in the manual that came with the air conditioner. I'm sure it would tell you all about how the air conditioner can sense the outside temperature. Quote me what it says.
    Thank you.
            Good luck.
                Peter
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I stand corrected.
Then why does a refrigerator in a garage quit working when the garage gets cold?
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Alot of portable home dehumidifiers start to freeze up below 60f its their design. Regular home refrigerators have a low temp operating range also. They are designed for use in a heated area .
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(TOM KAN PA) wrote:

Same principle exactly, just at a different thermostat set point (typically 72-75 degrees for air conditioning a house, 38-40 degrees inside a refrigerator). Your air conditioner won't run when it's 40 degrees outside, either.
To put it a bit differently: if the garage is at 32 degrees, you don't even *need* a refrigerator to keep your food cold, do you? You could unplug the fridge, and prop the door open.
-- Regards, Doug Miller (alphageek-at-milmac-dot-com)
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Actually, your central AC or window AC will work very nicely if it is warm inside and it is 40F outside.
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Christopher A. Young
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(TOM KAN PA) wrote:

gets
(typically
outside,
even
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Hi Stormin, hope you are having a nice day
On 18-Aug-03 At About 01:26:01, Stormin Mormon wrote to All Subject: Re: Need AC operation explained ! ! !
SM> Actually, your central AC or window AC will work very nicely if it is SM> warm inside and it is 40F outside.
You are totally wrong here. anything less than 60 degrees or so will probably freeze the coil and damage the compressor.
-=> HvacTech2 <=-
.. "After they make styrofoam, what do they ship it in?" - s.w.
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=Did ya tell her? She's gotta love that :-) ==
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