@mckinney3 wrote:
I have entered my responses in-line. >>>> <<<<<
I have been through a lot of frustration with Nest thermostats. Sometime they are too smart for the simple tasks that I need. So a specific issue I need help with:
Yesterday, I received a message on the actual thermostat display. The subject was something about the NEST system was going to figure out optimum settings as we move into a new season, etc. First, my system was stuck and did not execute the schedule settings for set points. When I went to investigate why the system was not running, I found that the temperature was 74 degrees versus the set point of 68 degrees. Hmmmm.... But the compressor was running but not the air handler so no cool air was being moved. ( as an aside, I do wonder what happens in that case with the coil, etc.)
>>> if you are attempting to maintain 68°F in your home, that is freaking cold. Since you say the outdoor compressor unit was running, and the indoor air handler was not running, then your indoor coil should be all iced up. Since no warm air is passing through the indoor coil, the cold refrigerant is returning outdoors very cold can run the risk of damaging the compressor if it does not have an accumulator tank . This is similar to a completely plugged air filter type of a problem; poor or no airflow over evaporator coil. Try to manually turn on the blower fan. Does it turn on? If not, there is a problem that requires HVAC service technician. <<<<<<<
I punched the thermostat face plate and the message disappeared and I could se the actual temperature and high low set points. Also at that time of day the Fan should be running all the time. The thermostat indicated (icon) that fan was running but it was not.
>>>>> This appears to be a problem with the air handler. Need to investigate the blower motor control system, if it is a PSC motor, check the capacitor. If it an ECM motor you need to verify the control wiring and supply voltages. This will require a service technician with an ECM motor test equipment. <<<<<<<
So, I figured there must be a coincidence and reset the cooling set point to a higher value and the compressor indeed shut off. I figured I would investigate further the next day (good luck with a service person on a holiday weekend.) I didn't want the compressor just running and running as the thermostat cooling SP would never be satisfied as the air handler was not running.
>>> what testing of your system did this service technician perform and what was the failing component that the technician replaced?<<<<<<
Well, around 2:00 AM, I hear the air handler start running even though the cool SP was satisfied. Went back to bed. Today, the system seems to be operating as expected.
>>>> You mentioned you fan should be on, so are running a fan schedule and did that turn your fan on at 2:00 am? <<<<<<
I am reminded of a similar situation 2 years ago in the heat of the summer while we were on vacation. I returned to a very hot house as the system failed to run as expected and YES, the thermostat had the same message. Upon receipt. That is twice that the receipt of that message seems to cause the system to go wonky and cease to operate as expected. =(
>>>>>> The Nest Learning thermostat uses Google geographic and Weather data to determine the seasonal changes. This can be disabled however, the feature of the ECO warm and cool setting have priority over automatic schedule. The change is part of the Home and Away feature. Remember, the driving goal of the Nest is to save your money by maximizing electrical energy consumption. <<<<<<<
I just don't trust the NEST Thermostats. I have simple day/night heat/cool needs and I like the programmable feature but when the thing goes off on a tangent, it is frustrating!
>>>>> If you do not want to use any of the advanced energy saving features of your Nest Learning Thermostat, simply go into setting and turn them off. Use your Nest App, tap your Thermostat, them tap the settings gear ⚙️ in the upper right corner. Then scroll down turning OFF:
- Home and Way OFF
- Auto Schedule OFF
- Early On OFF
- Cool to Dry OFF
Then tap ECO temperatures and rest to defaults:
Heat to 50°F
Cooling system OFF
Now tap Safety Temperatures and reset to defaults:
Heating set point 40°F., cooling system OFF
Now Tap Fan Schedule and slide the On/OFF to OFF.
At this point you will have disabled all of the energy saving functions and the system safety features. <<<<<
I hope someone can shed light on what happens and how to avoid/mitigate the situation.
>>>> I hope that this helps you do what it is you wanted to do; make an advance smart thermostat act like a non-advanced feature thermostat. <<<<<<
AC Cooling Wizard
