@econner I've checked your case and I saw that they emailed you and wanted to get the serial no. and receipt of your Nest Protect. You may reply to them and provide the information they're asking to help you.
@KeithSwanson I'm sorry to hear if your Nest Thermostat has a W5 error. We'd be happy to take a look into this for you. Please fill out this form with all the needed information. Let me know once you’re done.
@allimagater may I know what seems to be the problem of your Nest Protect?
Keeps us posted.