inside fan running, outside unit fan and compressor only run 5 minutes


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Old 08-05-09, 08:41 PM
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inside fan running, outside unit fan and compressor only run 5 minutes

My AC inside unit runs well, but outside unit only runs for 5 minutes every time I start the AC, and then outside unit stops. It sends cool air into my house only for 5 min. Two different techs came, one could not tell where the problem is. A second tech came and changed capacitor and contactor but the problem still exists. The outside unit does not make noise when it is on. And it seems like outside unit working just fine after midnight. If I want the outside unit kick on I have to turn off the whole AC unit and turn it back on 30 min later. But it only works for 5 minutes. We really need someone's help from this forum.
 
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Old 08-06-09, 04:31 AM
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Could be many things, did either tech check the refrigerant charge?
 
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Old 08-06-09, 06:39 AM
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Yes, they did. The refrigerant charge is normal. I am wondering why it works fine after midnight. It seems like when outside temperature is high it only works for 5 min then stops
 

Last edited by stickshift; 08-07-12 at 10:37 AM. Reason: removed quoting of entire post
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Old 08-06-09, 07:19 AM
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When you say the outside unit does not make noise when its on what do you mean?

You can see the cond fan running and you are getting cold air inside but there is no sound from the cond unit.

Do you have a programable stat? If so did you check the program?

Did the unit run for more then 5 min when the techs were there?
 
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Old 08-06-09, 08:00 AM
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We do not have programable stat. We have changed stat twice. The problem did not get fixed. The noise I meant is the outside unit sounds normal when it runs smoothly, it does not make fuzzy noise. Some people says their compressor makes noise trying to kick on. My AC unit does not do it at all. It just stoped working propertly when the sun rises up. It must be some kind of temperature related problem I think. So frustrating...
 

Last edited by stickshift; 08-07-12 at 10:38 AM. Reason: removed quoting of entire post
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Old 08-06-09, 09:00 AM
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Did the unit run for more then 5 min when the techs were there?
Did it?

The compressor does have a thermal overload, it makes sense that it would cut out when its hot out and working the hardest
but the tech should have seen that. As I stated before, alot of things could be going on, very difficult to diagnos this from here. I believe its a refrigerant issue. Did they record superheat or pressure and temp readings on the work order.

Are using a home warranty company?
Are both techs from the same company?
 
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Old 08-06-09, 01:02 PM
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Yes, the unit did run for about 8 mins when the tech was here. He said that was not a good sign. He replaced the contactor and capacitor, but it did not help at all. He did check refrigerant and told me it was fine. Two guys came from the same company, and they came separately. The second guy is a senior tech. None of them recorded superheat or pressure and temp readings. Do you think I need to replace the compressor, or is there any way to tell if the thermal is bad and needed to be replaced or fixed?
Thanks for your inputs.
 

Last edited by stickshift; 08-07-12 at 10:38 AM. Reason: removed quoting of entire post
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Old 08-06-09, 04:36 PM
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WHERE to start!!! Senior tech OJT 6 months. Can,t do much in 8 min.Is the condencer clean,can you see some light through it? Was an amp reading taken? You should stay with it and watch to see what shuts off first,the outside fan or the compressor. If its not a realty company find another service company. Sometimes a fan will run and sound good for a few minutes than stop.You should feel air going in on the sides out the top. Has the unit been worked on in the past year?
 
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Old 08-06-09, 04:59 PM
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I suggest you contact the service manager of the company and have him come out. Sounds like there "parts" changing to me. Still think its a refrigerant issue, either cut your losses and call a factory autherized service provider or make them make it right.
And no, you can't replace or fix a thermal overload on a compressor. Its internal and doing its job......sorry
 
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Old 08-06-09, 07:35 PM
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Does this unit have a short cycle timer installed. If so bypass it and see what happens.
 
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Old 08-06-09, 08:41 PM
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Another tech from different company came this evening. He could not figure it out either. All the readings he took were fine.

No, there is no short cycle installed.
 
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Old 08-07-09, 04:49 AM
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Post his readings..........
 
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Old 08-07-09, 03:28 PM
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As dun11 said post the readings if you have them. Seems very odd three techs have not a clue. Amps is the main reading needed sence its unlikely you have pressure switches. Did you notice what shuts off first,the fan or compressor?Is the small line going into the house getting hot? Is this a heatpump?
 
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Old 08-07-12, 10:10 AM
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My AC is doing the same thing. The tech came out and did all the test then told me my compressor was bad. As he was putting the outside cover on the unit kicked on. He did all the test again and could not find anything wrong.
 
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Old 08-07-12, 10:45 AM
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Billy:

I would normally move a question like yours on a several year old thread to a new thread for better visibility but figure you're likely to check back here first - please read the rest of the responses in this thread and try to get the information requested. After that, I would recommend starting a new thread with your questions and data, as the responses will be better that way.
 
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Old 08-08-12, 08:42 AM
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Have them look for a compressor discharge temperature sensor; if it has one there are a number of things that can cause that senor to shut-down the compressor.

Does the entire condensing unit, fan & compressor shut-down at the same time?


Simple easy anyone can do, ways to check the performance of your central air conditioner so, if needed; you can call an Energy Efficiency HVAC Technician & provide them some documented data clues.

If U want me to run a ballpark analysis of how your system is performing in respect to its 'Nominal Rated Btuh' we need at least the following numbers:

Performance Data Collection:
*All U need is a good thermometer (digital reading in tenths preferable) & and indoor Humidity Gauge

1) Helpful; Tonnage & SEER of Unit &/or outdoor condenser model number: __________________

2) TXV or, orifice metering device? _______. Only if U know…

3) Outdoor condenser’s discharge-air-temperature ______-F
Subtract Outdoor air temperature: _______
Outdoor Condenser Air-Temp-Split _______

4) Need the ‘Indoor’ percent of relative humidity - in the middle of the rooms or, at Return-Air inlet grilles ___
5) Indoor Return-Air Temperature ______
Subtract Indoor Supply-Air Temperature ______ -F
Indoor temperature-split _______-F

If U can find a turn in the small liquid line insulate the temperature-probe; get its temperature for the subcooling analysis:
Small liquid line temperature ____F

To measure return air the wet bulb temp, wrap a small/thin, wet (not dripping) piece of cloth around the probe and put it into the Return Air grille & then close to the closest Supply Air diffuser near the air handler (need air movement). Wait until the temperature stabilizes - may take a little while.

Return Air wet bulb ____F
Supply Air Wet Bulb ____F

Need the above information for troubleshooting & performance analysis.
 
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Old 09-06-14, 09:46 AM
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This is a real common topic so after reading thru it - please feel free to post your questions in a new thread. A make and model number of the system is always a help to us.
 
 

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