Connecting two Nest doorbells to a single chime is possible with the right setup and wiring. This guide walks you through compatible models, wiring tips, and smart configuration to ensure both doorbells ring your chime reliably.
Key Takeaways
- Compatibility matters: Only certain Nest doorbell models (wired) can share a chime—check your model before starting.
- Use a compatible chime box: Mechanical or digital chimes must support dual-doorbell wiring to avoid damage.
- Proper wiring is essential: Both doorbells must be wired in parallel to the same chime terminals for synchronized ringing.
- Transformer power requirements increase: Two doorbells need more power—upgrade your transformer if needed (16–24V, 20–40VA).
- Label wires clearly: Mark each doorbell’s wires to avoid confusion during installation.
- Test before finalizing: Always test the chime after wiring to ensure both doorbells trigger it correctly.
- Use the Google Home app: Configure both doorbells separately in the app for notifications and video feeds.
How to Hook Two Nest Doorbells Up to One Chime
If you’ve got a large home, multiple entry points, or just want extra peace of mind, installing two Nest doorbells might be the perfect solution. But what if you only have one indoor chime? Can you connect both doorbells to the same chime unit? The short answer is yes—but it requires careful planning, the right equipment, and proper wiring.
In this comprehensive guide, we’ll walk you through everything you need to know about hooking up two Nest doorbells to a single chime. Whether you’re a DIY enthusiast or working with an electrician, this step-by-step tutorial will help you get both doorbells ringing in harmony—without frying your chime or overloading your transformer.
We’ll cover compatibility checks, wiring diagrams, power requirements, safety tips, and troubleshooting common issues. By the end, you’ll have a reliable dual-doorbell system that keeps your home secure and your chime singing every time someone’s at the door.
Why Connect Two Nest Doorbells to One Chime?
Visual guide about How to Hook Two Nest Doorbells Up to One Chime
Image source: netatmostatic.blob.core.windows.net
Before diving into the how-to, let’s talk about the “why.” Why would someone want two doorbells on one chime?
First, convenience. If your home has a front and back door—or a main entrance and a side gate—having a doorbell at each location means you’ll never miss a visitor. But running separate chimes can be noisy and confusing. A single chime simplifies things: one sound, one response.
Second, cost efficiency. Instead of buying two chime units or upgrading to a more complex intercom system, connecting both doorbells to one chime saves money and reduces clutter.
Third, smart integration. Nest doorbells work seamlessly with the Google Home app. With two units, you get live video feeds, motion alerts, and two-way audio from both entrances—all manageable from your phone.
Finally, aesthetic consistency. Using the same chime sound across both doors creates a unified experience. You’ll know instantly when someone’s at either door, without guessing which chime is ringing.
Are Your Nest Doorbells Compatible?
Not all Nest doorbells can be wired to a single chime. The key factor is whether your models are wired (not battery-powered).
As of 2024, the following Nest doorbell models support wired installation and can be connected to a chime:
– Nest Doorbell (wired) – 2nd generation (2021)
– Nest Doorbell (wired) – 1st generation (2018)
The Nest Doorbell (battery) models cannot be directly wired to a chime because they’re designed for wireless operation. While you can use a Nest Chime Connector (sold separately) to link a battery doorbell to a mechanical chime, it only works with one doorbell per chime. So if you’re planning to connect two doorbells to one chime, both must be wired models.
Pro Tip: Check the back of your doorbell or the box it came in. Wired models will have terminals for “Front,” “Trans,” and “Rear” (or similar). Battery models won’t have these.
Check Your Chime Box Compatibility
Your indoor chime must support dual-doorbell wiring. Most traditional mechanical chimes (the ones with two brass strips that strike a bell) can handle two doorbells—but only if they have three terminals: Front, Trans (Transformer), and Rear.
Here’s how to identify a compatible chime:
– Mechanical chimes: Look for a rectangular box with two small bells or dome-shaped covers. Open the front panel (usually with a screw) and check the terminal labels.
– Digital chimes: These often have electronic boards and may require specific wiring. Check the manufacturer’s manual—some digital chimes support dual-doorbell setups, but not all.
If your chime only has two terminals (Front and Trans), it’s not suitable for two doorbells. You’ll need to upgrade to a dual-terminal chime or use a relay system (more on that later).
Warning: Never force two doorbells into a single-terminal chime. This can cause short circuits, damage the chime, or even create a fire hazard.
Assess Your Transformer’s Power Capacity
Every wired doorbell relies on a transformer to convert household voltage (120V) to a safer, lower voltage (typically 16–24V). When you add a second doorbell, you double the power demand.
Most standard doorbell transformers provide 10–16VA (volt-amperes). A single Nest doorbell needs about 8–10VA to operate reliably. Two doorbells will need at least 16–20VA, and ideally 24–40VA for consistent performance—especially if you’re using features like continuous video recording or night vision.
Here’s how to check your current transformer:
1. Turn off power at the circuit breaker.
2. Locate the transformer—usually near your doorbell chime, in the basement, attic, or electrical panel.
3. Look for a label with voltage (V) and VA ratings. Common markings: “16V 10VA” or “24V 20VA.”
If your transformer is rated below 16VA, or if it’s old and buzzing, it’s time to upgrade. A 24V 30VA transformer is a safe, future-proof choice for two Nest doorbells.
Pro Tip: Buy a transformer with a slightly higher VA rating than needed. This reduces strain and extends the life of your system.
Gather Your Tools and Materials
Before starting, make sure you have everything you need. Rushing out for parts mid-installation can be frustrating.
Here’s a checklist:
– Two Nest Doorbell (wired) units
– Compatible chime box (with Front, Trans, and Rear terminals)
– Doorbell transformer (16–24V, 20–40VA recommended)
– Low-voltage doorbell wire (18–22 gauge, 2-conductor)
– Wire strippers
– Screwdrivers (Phillips and flathead)
– Voltage tester (non-contact)
– Electrical tape or wire nuts
– Labels or colored tape (to mark wires)
– Drill and bits (if running new wires)
– Ladder (for high installations)
– Optional: Wire fish tape (for running wires through walls)
Safety First: Always turn off power at the breaker before working on electrical components. Use a voltage tester to confirm the wires are dead.
Step-by-Step: Wiring Two Nest Doorbells to One Chime
Now for the main event: connecting both doorbells to a single chime. We’ll use a parallel wiring setup, which ensures both doorbells can trigger the chime independently.
Step 1: Turn Off Power
Safety is non-negotiable. Go to your electrical panel and turn off the breaker that powers your doorbell circuit. Use a non-contact voltage tester at the chime box to confirm no power is flowing.
Step 2: Remove the Old Chime Cover
Unscrew the front panel of your chime box. You’ll see three terminals: Front, Trans, and Rear. The “Trans” terminal connects to the transformer. The “Front” and “Rear” terminals are for doorbell wires.
If your chime only has two terminals, you’ll need to upgrade it or use a relay (see troubleshooting section).
Step 3: Label and Disconnect Existing Wires
If you’re replacing an old doorbell, carefully disconnect the wires from the terminals. Use labels or colored tape to mark which wire goes where. For example:
– Red wire → Front terminal
– White wire → Trans terminal
This prevents confusion when adding the second doorbell.
Step 4: Run Wires to Both Doorbell Locations
You’ll need to run low-voltage wire from the chime box to each doorbell location. If you’re adding a second doorbell where there wasn’t one before, this may involve drilling through walls or baseboards.
Use 18-gauge, 2-conductor wire (often called “doorbell wire”). One wire will carry power from the transformer, and the other will complete the circuit when the button is pressed.
Pro Tip: Run both wires in the same conduit or channel to simplify future maintenance.
Step 5: Connect Wires at the Chime Box
Now, wire both doorbells in parallel:
– Connect the transformer wire (from the “Trans” terminal) to a common wire that splits to both doorbells. Use a wire nut or terminal block.
– Connect one wire from Doorbell 1 to the “Front” terminal.
– Connect one wire from Doorbell 2 to the “Rear” terminal.
This setup allows either doorbell to complete the circuit and ring the chime.
Example Wiring Diagram:
“`
Transformer → [Trans Terminal]
↓
[Common Wire]
↙ ↘
[Front Terminal] [Rear Terminal]
↓ ↓
Doorbell 1 Doorbell 2
“`
Step 6: Install the Nest Doorbells
At each doorbell location:
1. Remove the old doorbell (if present).
2. Connect the two wires to the Nest doorbell’s terminals. It doesn’t matter which wire goes where—Nest doorbells are polarity-insensitive.
3. Secure the doorbell to the wall using the included mounting plate and screws.
4. Attach the faceplate.
Pro Tip: Use the Nest app’s “Check Power” feature during setup. If it says “Low Power,” your transformer may be underpowered.
Step 7: Restore Power and Test
Turn the breaker back on. Wait a few seconds, then press each doorbell button.
– Both should ring the chime.
– The chime should sound the same for both (unless your chime has different tones for Front/Rear).
– Check the Nest app for live video and notifications.
If only one doorbell works, double-check your wiring. If neither works, verify the transformer is live and properly connected.
Configure Both Doorbells in the Google Home App
Wiring is only half the battle. You also need to set up both doorbells in the Google Home app so you can receive alerts and view video feeds.
Step 1: Open the Google Home App
Download or open the Google Home app on your smartphone or tablet.
Step 2: Add the First Doorbell
1. Tap the “+” icon and select “Set up device.”
2. Choose “New device” and follow the on-screen instructions.
3. Scan the QR code on the back of the first Nest doorbell.
4. Connect to your Wi-Fi network.
5. Name the doorbell (e.g., “Front Door”).
Step 3: Add the Second Doorbell
Repeat the process for the second doorbell:
1. Tap “+” → “Set up device” → “New device.”
2. Scan the QR code on the second doorbell.
3. Connect to the same Wi-Fi network.
4. Name it (e.g., “Back Door”).
Important: Both doorbells must be on the same Wi-Fi network. If you have a mesh system, ensure both locations have strong signal.
Step 4: Customize Settings
Once both are added, customize each doorbell:
– Set motion zones to avoid false alerts.
– Adjust notification preferences (e.g., only notify for people, not packages).
– Enable “Doorbell Press” notifications.
– Set up “Quiet Time” if you don’t want alerts at night.
You can also create routines. For example: “When the back doorbell rings, turn on the porch light.”
Troubleshooting Common Issues
Even with careful planning, problems can arise. Here’s how to fix the most common issues.
Chime Doesn’t Ring for One Doorbell
– Check wiring at the chime box. Ensure both doorbells are connected to separate terminals (Front and Rear).
– Verify the doorbell button is working. Test with a multimeter or replace the button.
– Make sure the transformer is providing enough power. A weak transformer may only power one doorbell.
Chime Rings Weakly or Intermittently
– This is usually a power issue. Upgrade to a 24V 30VA transformer.
– Check for loose wire connections. Tighten all terminals and wire nuts.
– Ensure wires aren’t damaged or corroded.
Doorbell Shows “Low Power” in the App
– The transformer is underpowered. Replace it with a higher VA model.
– Long wire runs can cause voltage drop. Use thicker wire (16-gauge) for distances over 50 feet.
– Avoid running doorbell wires near high-voltage lines, which can cause interference.
Only One Doorbell Appears in the App
– The second doorbell may not have connected to Wi-Fi. Re-run setup in the Google Home app.
– Check Wi-Fi signal strength at the second location. Use a Wi-Fi extender if needed.
– Reset the doorbell by holding the button for 20 seconds, then re-add it.
Chime Makes a Buzzing Sound
– This often means the chime is receiving too much voltage or the wrong type of signal.
– Ensure you’re using a mechanical chime, not a digital one, unless it’s rated for dual-doorbell use.
– Add a diode or relay if using a digital chime (advanced fix—consult an electrician).
Safety Tips and Best Practices
Working with electricity—even low-voltage—requires caution. Follow these safety tips:
– Always turn off power at the breaker before touching wires.
– Use insulated tools and wear rubber-soled shoes.
– Never work on doorbell wiring during rain or high humidity.
– Label all wires clearly to avoid mix-ups.
– If you’re unsure about any step, hire a licensed electrician.
Bonus Tip: Take photos of your wiring before and after installation. This helps if you need to troubleshoot later or sell your home.
Alternative Solutions
If wiring two doorbells to one chime isn’t feasible, consider these alternatives:
– Use wireless chimes: Plug-in wireless chimes can be placed anywhere and sync with your Nest doorbells via the app.
– Upgrade to a smart chime: Devices like the Ring Chime Pro or Google Nest Hub can act as chimes and display video feeds.
– Use a relay system: For complex setups, a relay can isolate the two doorbells and prevent interference.
Conclusion
Hooking up two Nest doorbells to one chime is a smart, cost-effective way to enhance your home’s security and convenience. With the right equipment—compatible doorbells, a dual-terminal chime, and a properly sized transformer—you can create a seamless dual-doorbell system that rings reliably and integrates beautifully with your smart home.
Remember: safety first, plan carefully, and test thoroughly. Whether you’re a DIY pro or calling in an expert, this guide gives you the knowledge to get it right the first time.
Now go ahead—install those doorbells, enjoy the peace of mind, and never miss a visitor again.