Is my extender breaking my Nest Learning Thermostat?

The short answer

Low data needs mean an extender is usually enough. Cheap extenders make a second network. Once your phone and the gadget end up on different halves of it, they can no longer find each other.

What's happening underneath

Cloud-based, so router filtering is rarely the issue. Position almost always is. An extender that makes its own network name puts your phone and the gadget on two different networks.

Source: Manufacturer documentation

Try these, in this order

• • Check the Wi-Fi signal on the thermostat itself in its settings menu.
• • Move the router off the floor and out of the meter cupboard.
• • Re-enter the Wi-Fi password on the thermostat after any router change.
• • Check the signal where the gadget actually lives, not where you're standing.
• • Move the router off the floor and out of any cupboard before buying anything.
• • Put the gadget and your phone on the same Wi-Fi name.
• • Restart the gadget before the router — it is quicker and it fixes more.

Setting it up again properly

• • Stand next to your router while you set it up, then move the gadget to where it lives.
• • Put your phone on the 2.4 GHz network name for the setup, or use one name for both bands so the phone can follow.
• • If your router splits bands into two names, turn the 5 GHz one off for five minutes rather than fighting it.
• • Turn mobile data off on your phone during setup — some apps quietly use it and never find the gadget.

When it's worth spending money

A mesh box in the hall, and only if signal there stays weak after moving the router.