HVAC Troubleshooting

Nest thermostat showing F16? That means a low-voltage wiring or power overload problem. Here is the no-nonsense way to clear it and get your heat or AC back.

F13 on a Nest thermostat usually means the system has hit a hard fault and the thermostat won’t run heating or cooling. Here’s how to tell if the Nest is dying or your furnace is locked out, and what to do about it.

Nest thermostat showing F8? That usually means the thermostat is losing 24V power from your HVAC system. Here’s the fast, practical way to track it down and fix it.

Straightforward guide to dealing with a Nest Thermostat F6 situation: what it really means, how to do the official reset steps, and how a tech separates a Nest problem from a furnace/boiler problem.

F2 on a Nest thermostat is a low-voltage power problem from your HVAC system, usually on the R/Rc side or missing/weak C wire. Here’s how to get power back and clear it.