I have 2 nest thermostats installed in the house. Up until a few months ago everything worked well but then just after I changed my internet provider the thermostat’s went off line. I had the man down who had installed the system but he couldn’t work it out. Can anyone throw any light on this problem?
Did you change the WiFi Network that the Nest Thermostats are connected to?
A new ISP typically means a new WiFi network name and password. You'll need to change them in each thermostat or just make the new system have the same name and password as the old one.