Our Nest Thermostat was showing error E298. We had never experienced this before. We also received a message that the WIFI was not connected. We looked through everything. We could not find the reason for the error.
We called the Heating and Cooling Company we work with to see if they could help. The tech looked over everything. He then went and checked our unit in the attic. He found condensation. When the red wire becomes wet (damp) because of moisture colllecting (80% humidity this morning). The unit has an automatic shut off to prevent a leak that would damage the home. He dried out the area, installed some spacers that would allow some air movement and turned the unit back on (automatic shut off). That fixed the thermostat. The red wire now functions with the thermostat as it should and the air conditioner was working perfectly.
