E195 after 3 years since installation

[Tetsuothecat]

Received an error code on the nest e for power. It's been working fine for 3 years. We have the heating, cooling, fan and R // power wire hooked up. I do not want to do the fan wire (g) to common wire (c) trick if I don't have to. Again it was working fine for 3 years why suddenly would it not be getting enough power? The system as a whole should be fine, but we were getting errors that the HVAC was shutting down intermittently (running for 5-15min then shutting down). Haven't had any power surges, and was fairly sure the other issue is a filter problem. Any ideas? 

[Markjosephp]

Hello Tetsuothecat,

I'm sorry to hear about the trouble you're experiencing with your Nest Thermostat E. If you're getting message codes related to power and your HVAC system is intermittently shutting down, there could be a few potential causes.

I appreciate that you've already checked the wiring, ensuring that heating, cooling, fan, and power wires are correctly connected. However, considering the intermittent shutdowns, it might be worth rechecking the wiring to see if there are any loose connections or if any corrosion has occurred over time.

Rule out power surges and suspect an air filter problem with your HVAC system, a clogged or dirty filter could indeed impact the system's efficiency. A restricted airflow may cause the system to shut down intermittently. Consider checking and replacing your air filter if it's dirty.

If the issue persists, please gather the power readouts in the Technical Info settings. I'll look forward to your response.

Regards,
Mark

[Tetsuothecat]

Hi - so I do believe it was the filter that overheated the system, then the system tried to restart which then triggered a lockout. The lockout shut off the power to the thermostat, hence the issue with the wire. So it was the HVAC and this was just a symptom

[Markjosephp]

Hi there,

It's usually like a cascading effect from the HVAC system overheating due to a filter problem, leading to a system restart and eventually triggering a lockout that affected the power to the thermostat. It's interesting to see how different components are interconnected in the HVAC system, and identifying the root cause will undoubtedly help prevent similar issues in the future.

If you have any further questions or need assistance with troubleshooting, feel free to ask. Also, here's an article that would help with Air filters and filter reminders.

Best,
Mark