How to Switch Out an HZ311 Thermostat for an Ecobee Premium Thermostat

Smart home Admin February 23, 2025

Upgrading from an HZ311 thermostat to an Ecobee Premium thermostat improves energy efficiency, smart home integration, and overall climate control. This guide provides step-by-step instructions for a smooth transition.

1. Tools and Materials Needed

✔ Ecobee Premium thermostat and included installation kit ✔ Screwdriver (Phillips and flathead) ✔ Wire labels or tape ✔ Smartphone or tablet (for Ecobee app setup) ✔ Voltage tester (optional, for safety) ✔ Drill (if new mounting holes are required)

2. Understanding Your HZ311 Thermostat System

The HZ311 is a zone control panel that manages multiple heating and cooling zones. Before switching, determine:

If you have a conventional (single-stage or multi-stage) or heat pump system.
The number of zones in your system.
Whether you need additional relays or a PEK (Power Extender Kit) to power the Ecobee.

3. Removing the HZ311 Thermostat

Step 1: Turn Off Power to the HVAC System

Shut off power at the breaker box to prevent electrical issues.
Confirm power is off using a voltage tester.

Step 2: Label Wires

Carefully remove the HZ311 thermostat cover.
Label each wire with stickers or tape to match its current terminal.

Step 3: Disconnect Wires and Remove the Old Thermostat

Unscrew each terminal connection and gently pull out the wires.
Remove the mounting plate if it does not align with the Ecobee’s mounting bracket.

4. Installing the Ecobee Premium Thermostat

Step 1: Mount the Ecobee Thermostat Bracket

Align the Ecobee wall plate with existing holes or drill new ones if needed.
Secure the bracket with screws.

Step 2: Connect the Wires

Refer to the Ecobee installation guide and match the labeled wires to the corresponding terminals:
- Rc or Rh → Power
- Y1 → Cooling
- W1 → Heating
- G → Fan
- O/B → Heat pump reversing valve (if applicable)
- C (Common wire) → Required for power (use the included PEK if missing)

Step 3: Attach the Ecobee Thermostat

Snap the Ecobee Premium thermostat onto the mounting plate.
Restore power at the breaker box.

5. Setting Up the Ecobee Premium Thermostat

Step 1: Follow the On-Screen Setup

Select your HVAC system type.
Configure zone settings if applicable.
Connect to Wi-Fi and sync with the Ecobee app.

Step 2: Test the System

Run a test to verify heating, cooling, and fan operation.
Adjust temperature settings and schedules in the Ecobee app.

Step 3: Integrate with Smart Home Devices

Connect Ecobee to Alexa, Google Assistant, Apple HomeKit, or other smart home systems.

6. Troubleshooting Common Issues

Issue: Ecobee Not Powering On

✔ Check if the C-wire is properly connected. ✔ Use the Power Extender Kit (PEK) if no C-wire is available. ✔ Ensure the HVAC breaker is switched on.

Issue: Incorrect Temperature Readings

✔ Calibrate the thermostat through the Ecobee settings. ✔ Move the thermostat away from heat sources or vents.

Issue: Heating or Cooling Not Working

✔ Verify wires are connected to the correct terminals. ✔ Check HVAC settings in the Ecobee app. ✔ Reset the thermostat and repeat the setup process.

7. Final Thoughts

Replacing an HZ311 thermostat with an Ecobee Premium thermostat enhances your home’s comfort and energy efficiency. By carefully following these steps, you can successfully complete the upgrade and enjoy smart climate control with advanced features.

Frequently Asked Questions (FAQs)

Do I need a professional to install an Ecobee thermostat?

Most users can install it themselves, but professional installation is recommended for complex zone systems.

What if my system doesn’t have a C-wire?

Use the included Power Extender Kit (PEK) to supply power to the thermostat.

Can I still control my HVAC zones with Ecobee?

Yes, but you may need additional zoning accessories or consult an HVAC technician.

By following this guide, you can seamlessly replace your HZ311 thermostat with an Ecobee Premium thermostat, improving energy efficiency and home automation integration.