Ring Video Doorbell F21 Error Code Fix

by

What This Error Means

F21 on a Ring Video Doorbell means the doorbell failed a firmware/update step and can’t finish booting or setup.

In plain terms: the doorbell powers up, tries to talk to Ring’s servers, chokes on the software update, and stays offline or stuck in setup with F21 on the app.

Official Fix

Do it in this order. Don’t skip steps.

  • 1. Check power first.
    – Wired model: Make sure the house breaker for the doorbell is ON and the old mechanical chime (if you have one) still works when you short the two doorbell wires together.
    – Battery model: Pull the battery, charge it to 100%, then snap it back in until you hear the click.
  • 2. Hard power-cycle the doorbell.
    – Wired: Flip the breaker OFF for 30–60 seconds, then back ON. Watch for the light ring to start spinning or flashing.
    – Battery: Remove the battery for 30–60 seconds, then reinstall.
  • 3. Clean up your Wi‑Fi.
    – Make sure you have a 2.4 GHz network enabled (most Ring doorbells prefer 2.4 GHz).
    – Turn off any “guest isolation” feature on the router.
    – Reboot the router: unplug 30 seconds, plug back in, wait 2–3 minutes.
  • 4. Re-run setup from the Ring app.
    – Open the Ring app > tap the doorbell > Device Settings > Remove Device (if it shows up).
    – Then tap “Set Up a Device” and follow the QR code / serial number steps.
    – Stay within 10 ft (3 m) of your router during setup if possible.
  • 5. Do a full factory reset.
    – Press and hold the setup button on the doorbell (orange/side/back button, model-dependent) for 15–20 seconds until the light ring flashes or spins.
    – Let it reboot fully (can take a couple of minutes).
    – Run setup again in the app after the light indicates setup mode.
  • 6. If F21 still shows, Ring wants you to call them.
    – At this point their script is: confirm power, confirm Wi‑Fi, confirm you did a factory reset, and then they either push firmware from their side or approve a warranty swap.

The Technician's Trick

Here’s what the field guys do when the app just keeps throwing F21.

  • 1. Use a phone hotspot to force the update.
    – Turn your phone into a hotspot (2.4 GHz if you can choose).
    – Give it a simple name and password (no spaces or weird characters).
    – Stand next to the doorbell, put it in setup mode, and connect it to the hotspot from the Ring app.
    – Let it sit 5–10 minutes after setup; this often lets the firmware finally download and install.
    – Once it’s stable, change Wi‑Fi in the app back to your home network.
  • 2. Bypass weak doorbell wiring.
    – If it’s a wired doorbell and the transformer is old (10VA, rusty, buzzing), it may not deliver clean power for an update.
    – Temporarily power the Ring with a 16–24VAC plug-in transformer right at an outlet near the door (or indoors with the doorbell off the wall).
    – Run setup and the update on that clean power, then put it back on the house wiring if you want.
  • 3. Deep-clean the app/account side.
    – Delete the doorbell from the Ring app.
    – Log out of the app, delete the app from your phone, reboot the phone, reinstall the app, log back in.
    – Now factory-reset the doorbell again and run setup like it’s brand new.
    – This clears out half-finished activations that can keep throwing F21.
  • 4. Still bricked?
    – Try the hotspot trick + clean power at the same time.
    – If F21 survives all that, the internal flash memory or radio is likely toast — push Ring for a replacement.

Is It Worth Fixing? (The Financial Verdict)

  • ✅ Fix: Doorbell is under 4–5 years old, was working recently, and responds to resets (lights change, chime clicks, sometimes comes online).
  • ⚠️ Debatable: Older transformer/house wiring, borderline Wi‑Fi, and you’ve already sunk hours into it — might be cheaper to upgrade the transformer and/or router along with the doorbell.
  • ❌ Replace: No lights, no sounds, F21 never clears even with clean power and hotspot tricks, and it’s out of warranty — don’t chase a zombie, buy a new unit.

Parts You Might Need

As an Amazon Associate we earn from qualifying purchases.