Yesterday our thermostat signaled "lo batt." Now the AC isn't working!

After replacing the batteries in the thermostat, I reprogrammed it. Unfortunately our ac unit did not start cooling the house again. The outside unit is running (I can hear and see the fan going), and I can hear the inside unit running. Any troubleshooting I can do before calling for service?

  4 answers
  • How long have you waited. After being off line, it take take a little bit in order for them to re sync. I would also check the. GFCI and see if that popped, if so re set it.
  • Karen Krysowaty Karen Krysowaty on Jul 30, 2017
    Time to call the specialists
  • Jason T. Lee Jason T. Lee on Jul 30, 2017
    I am a HVAC tech. Maybe I can help. You can see the unit is running the fan but you're now getting cool air so now you need to see why. Go to your out door unit (the condenser) and look for the copper lines that come out the back of the machine. There are two, the larger one usually has a black insulation over it. Uncover the large copper line just enough to touch the copper with your hand. If it is as cool as a can of Coke straight from the ice chest then your unit is operating perfectly if it has ice on it then it's time to grab the phone and call for service. If it's warm or it has the same temperature as the outside world you have a different issue and again it's time the call. If it has ice on the large copper tube then your system is either low on refrigerant or the air isn't blowing thru the indoor coil (evaporator) either way I can't exactly tell you what to do without teaching you to be a tech. I would bet from your description you need to have the refrigerant filled. Weak indoor airflow can be a symptom of a iced up coil blocking the air. If you find ice on the line shut the system off before you call a company so the ice can melt instlead of you tech having to wait.
  • Jason T. Lee Jason T. Lee on Jul 30, 2017
    sorry about my typing but big fingers on an iPhone isn't helpful
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