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Discussion Starter #1
Since it's hotter than the sun this week in So. Cal, of course I start having intermittent A/C problems. The house and all the units are less than 3 years old.

Problem: The A/C absolutely DOES WORK. If the house is 82* and I set the thermo to 78* it will get the house to 78*. But then the fun begins. It won't cycle the A/C to keep it at the set temp. So the house will temp will rise until I manually lower the thermo to 77* or lower. It's a constant manual changing of the thermostat that is now very annoying.

Do I have a faulty switch somewhere? Is the in-house thermostat control on its way out?

I'll probe and/or fix almost anything, but I know absolutely nothing about HVAC.

I'm calling the original installer company this morning, but I'm hoping for some pre-emptive advise so I don't get scammed into overpaying. :thumbsdown:
 

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Sounds to me like the thermostat in the house is f'ed. They are what "call for AC" and cycle the aC unit on/off to maintain the temp. My thermostat is an old mechanical (mercury switch) Honeywell and you can watch this happen as the mercury make contact. No mystery to troubleshooting those, but how you can easily test the newfangled ones is beyond me. I guess you could always rip it off the wall and go after it with a DMM to see if it's closing the circut or whatever it's supposed to do?? :shrug: That's not exactly simple though :lol:

Edited to add: I'm not a trained pro, but I did stay at a Holiday Inn last night. :pirate:
 

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Discussion Starter #3
New Thermostat is about $50 vs a $150 minimum service call. All of the major components are still warrantied, but they don't come out for free...of course.

Looks like I'll try a new thermostat after I go through all of the current settings.
 

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Will they provide you with a new thermostat without installation and still under warranty?
 

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hotter than the sun = true.

thermostat sounds like a likely candidate. Got one you can borrow / swap out to test from your neighbor for an adult beverage?
 

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Before you run out and buy anything I'd double check how you are "setting" the thermostat. It sounds like you are not storing the setting but calling for a one time temp adjustment.
My wife is one who likes to adjust the thermostat whenever it gets really hot or cold on a particular day. She can't seem to grasp that the temp indoors remains constant. Drives me nuts. To the point, she will invariably mess with the thermostat to the point I have to reprogram it to get I functioning properly. Of course this is the same woman who will set an oven to 500 degrees instead of the required 375...since it will heat up faster that way!
I'm done trying to explain things at this point.
 

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Discussion Starter #7
T-Bob -

I understand completely. Except our Thermostat use consists solely of switching from "Off" to "Cool" which is set to 78*. So when I/We get home from work, I just move the switch to "cool" and it does the rest.

I'm not really sure how much the programming adjustment is going to do. I guess we don't technically "set" the thermostat schedule at all.

I turn the A/C off when we go to bed, and live with fans and open windows all night.
 
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