01-28-2024 06:41 AM
Hello! I have a heat only system. It was two wires, so I installed the C Connector module to run the Nest thermostat. About every 30-45 days I get a "battery low" message and "need to connect power" message. I checked the wiring of the C connector and it is to spec, I can only assume the C terminal on my heating unit is not pushing much power. I do not have a multimeter to check, are there alternatives for connecting the C wire?
01-31-2024 09:22 AM
Hi Mudfoots,
Uh-oh! If you have a heat-only system and you're experiencing frequent "battery low" messages on your Nest Thermostat, it could indicate that the C wire connection is not providing enough power to keep the thermostat charged. Here are a few alternatives you can consider to connect the C wire:
It's important to note that implementing these alternatives may require some electrical knowledge and potentially working with high voltage. If you're not comfortable with electrical work or are unsure about the compatibility of your heating system, it's recommended to consult with a professional HVAC technician or an electrician. They can assess your system, recommend the best solution, and ensure that the installation is done safely and correctly.
Let us know how it goes.
Best,
Zoe
02-06-2024 05:57 AM
Thanks Zoe,
I have been looking all over for the power requirements for the nest thermostat and could not find anything specific. It is getting about 3.5v from the c wire as it sits, but until I know the power requirements, I will not know how to properly proceed. I have the c-wire adapter already installed, so my thoughts is that because this is an older house (1800's draaaaaaafty) that the unit simply runs for a while, drains the power, and sets off the message and I should just ignore it and focus on insulation issues...hahahahaha!
Cheers,
Tony
02-08-2024 11:13 AM
Hi there,
Thanks for getting back to us. The Nest Thermostat typically requires a 24V AC power supply to operate properly. It's important to note that the C-wire (common wire) is intended to provide a continuous 24V AC power supply to the thermostat, ensuring its stable operation and preventing power drain issues.
If your Nest Thermostat is currently receiving only around 3.5V from the C-wire, it's likely not receiving enough power to function correctly. This can result in various issues, including intermittent operation, error messages, or unexpected shutdowns. Could you list down the power readings of your thermostat's VIN, IIN, PS-* under Settings > Equipment > Power Info so I can take a closer look?
Regards,
Zoe
02-09-2024 07:43 PM
VIN:33.064V LIN :385(w) PS: W0385, WP-24
It had a error on it when I woke it to get that info; but the error was a weblink that disappeared, so it was useless. Ran a power test, all good. Battery says good as well.
Thanks for your help!
02-11-2024 10:34 AM
Hello Mudfoots,
Awesome! I'm glad that everything has been sorted out. If you have questions or concerns in the future, feel free to start a new thread, and we'll be happy to help.
Thanks,
Zoe