Google Nest Thermostat Boiler Not Firing: How to Fix It

Q: Why is my Nest calling for heat but boiler not responding?

This usually indicates a wiring issue between the Heat Link and boiler, a boiler fault, or incorrect Nest settings. Check all connections are secure and verify your boiler type is correctly configured in the Nest app.

Q: Can a faulty Heat Link cause my boiler not to fire?

Yes, if the Heat Link isn't sending the correct signals to your boiler's control system, it won't fire even when heating is demanded. Test by disconnecting Nest and operating the boiler manually.

Q: How do I know if the problem is with Nest or my boiler?

Disconnect the Heat Link and try operating your boiler manually. If it works manually but not through Nest, the issue is with the Nest system. If it doesn't work manually, the boiler needs professional attention.

Q: Is it safe to reset my boiler multiple times?

No, only reset once and wait 5 minutes between attempts. Multiple rapid resets can damage the boiler's ignition system and safety controls. If it doesn't fire after 2-3 resets, call a professional.

Q: What should I check if my boiler has power but won't ignite?

Check gas supply, boiler pressure (1-1.5 bar), that the flue isn't blocked, condensate pipe isn't frozen, and look for error codes on the boiler display. These are common causes of ignition failure.

Abstract

When your Google Nest thermostat shows 'boiler not firing', it means the Heat Link is successfully calling for heat, but your boiler's burner isn't igniting to produce hot water or heating. This is a common issue that can often be resolved with basic troubleshooting steps before calling a professional.