Air Conditioner is not cooling well and large copper pipe is hot

Old 05-26-19, 12:32 PM
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Air Conditioner is not cooling well and large copper pipe is hot

We recently got a new air conditioning unit and thermostat. When we turn the air conditioning on to cool with an internal temperature starting at 82F, and the fan temperature set to less than 70F. After a while, the internal temperature either stays at 82 or even rises, indicating that the house is not actually cooling. When we went outside to check the air conditioner, we noticed the larger copper tube with some black insulating foam on it can be felt at the end to be VERY hot, almost too hot to touch when it's not nearly as warm outside. The smaller, thinner copper tubing is cool to the touch, almost equal to the outside temperature if not cooler. What are these tubes called? Are they functioning normally? Is it supposed to be so hot? And if not, how would we go about fixing it? Thank you.
Old 05-26-19, 12:48 PM
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The large copper tubing with the insulation should be cold, while the smaller diameter copper tubing should be warm. When the thermostat calls for cooling, is the outside unit running? The condenser fan on top of the unit should be blowing warm air out the top, and the compressor should be running.

If the outside unit is running, my guess is that the system is low on refrigerant. Since it sounds like the system is relatively new, you should contact the installer and ask him to check the system over.
Old 05-26-19, 03:42 PM
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It almost sounds like it is running in reverse. Is the unit outside a heat pump?
Old 05-26-19, 04:07 PM
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If its new, why not call the installer back?

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