Hi there and thanks for reaching our Community. I'm sorry to hear about your issue, but I'll do my best to help you out. I'll need to get some extra info about your inquiry, so please answer the following questions:
What type of Nest thermostat do you have?
When was it installed?
Are you seeing any wiring reports or errors on the thermostat and/or the app?
Have you recently had service or maintenance on your electrical, plumbing, or heating system?
Were there any power outages?
Have you tried any troubleshooting steps before contacting us?
Also, please make sure that you checked the following:
Step 1: Check if the Heat Link is powering on.
Step 2: Check the batteries in the Thermostat E Heat Link
Step 3: Check if the issue is due to a power outage.
Step 4: Check if the cause may be related to the initial installation.
Step 5: Check if there has been any recent electrical or plumbing work carried out.
Step 6: Check that the breaker switches are set to on.
Step 7: Turn the fuse board switches (circuit breakers) off and on.
Step 8: Turn on Manual Mode to verify boiler activation.
