Smart Thermostat ecobee4

ecobee4 Smart Thermostat Installation EB-STATE4-01

The ecobee4 is a smart thermostat designed to control compatible residential heating, cooling, and ventilation equipment. It features a touchscreen interface, temperature adjustment controls, indoor humidity monitoring, built-in voice control, and support for a room sensor.

The thermostat can be installed using an existing C-wire or the included Power Extender Kit (PEK). A C-wire provides the continuous 24 VAC connection needed to power the thermostat. For compatible HVAC systems without a C-wire, the PEK provides an alternative installation method.

The ecobee4 supports conventional heating and cooling systems with up to two stages of each. It also supports compatible air-source and geothermal heat pumps, auxiliary heating, boilers, radiant heating, and selected HVAC accessories.

Installation begins by turning off the HVAC system and checking the existing thermostat wiring. The process then follows one of two installation methods:

• Guide 1: Installation with an existing C-wire.
• Guide 2: Installation without a C-wire using the Power Extender Kit.

After the thermostat is mounted and connected, the display automatically guides users through setup and registration.

Important: The ecobee4 is designed for 24 VAC systems with a maximum current of 2 A. It must not be connected to high-voltage or millivolt systems. The limited warranty excludes products not installed by a licensed HVAC contractor.

Product Overview

The ecobee4 combines heating and cooling control with connected home features.

Its touchscreen displays the current indoor temperature, humidity, system mode, weather information, and temperature adjustment controls.

The thermostat also provides Home and Away controls, scheduling, vacation settings, and voice control options.

Main Features

• Smart temperature control: Adjusts the desired indoor temperature through the touchscreen.
• Heating and cooling modes: Supports Heat, Cool, Auto, and Off.
• Two-stage heating and cooling: Works with compatible conventional HVAC systems.
• Heat pump support: Supports compatible heat pump systems with auxiliary heating.
• C-wire installation: Uses an existing common wire for continuous power.
• Power Extender Kit: Supports certain HVAC systems without a C-wire.
• Room sensor: Includes a separate room sensor and stand.
• Indoor humidity display: Shows current humidity levels.
• Weather information: Displays local weather and the weekly forecast.
• Voice control: Provides microphone and volume controls through the thermostat.
• Quick Changes: Allows switching between Home and Away.
• Scheduling: Supports temperature scheduling.
• Vacation settings: Provides temperature control for planned absences.
• Wi-Fi setup: Supports connected thermostat setup and registration.
• Accessory connections: Supports compatible humidifiers, dehumidifiers, and ventilators.
• Apple HomeKit: Identified in the product’s legal information.

Compatible Heating and Cooling Systems

The ecobee4 supports several HVAC configurations.

HVAC Compatibility

Electrical Compatibility

The ecobee4 requires:

• A compatible 24 VAC HVAC control system.
• A maximum current of 2 A.
• An existing C-wire or supported PEK configuration.

Warning: Do not connect the ecobee4 to 110V, 120V, or 240V line-voltage wiring.

What’s Included in the Box

The ecobee4 package contains the thermostat, installation hardware, room sensor, and Power Extender Kit.

Tools Required

Optional Tools

• Hammer.
• Pencil.
• Wire stripper.

Parts and Components

The ecobee4 installation system includes the thermostat, backplate, terminal blocks, room sensor, and Power Extender Kit.

ecobee4 Wiring Terminals

The thermostat backplate provides terminals for HVAC power, heating, cooling, fan operation, heat pumps, and accessory equipment.

Rc and Rh Terminals

The ecobee4 handles the connection between Rc and Rh internally when appropriate.

Do not install jumper wires between Rc and Rh.

When there is only one R, Rc, or Rh wire, connect it to the ecobee4 Rc terminal.

When separate Rc and Rh wires are present, connect them to their corresponding terminals.

Important Safety Instructions

The ecobee4 connects to HVAC control wiring and must be installed according to the electrical requirements.

Electrical Safety

• Turn off HVAC power before beginning installation.
• Use the HVAC master switch or circuit breaker.
• Confirm that the heating or cooling system cannot start.
• Do not connect the thermostat to a line-voltage system.
• Do not connect the thermostat to a millivolt system.
• Do not exceed the 24 VAC, 2 A electrical rating.
• Do not touch energized HVAC wiring.
• Follow the correct wiring arrangement for the installed equipment.
• Secure all wires inside the terminals.
• Close the HVAC cover panel before restoring power.

High-Voltage Warning

Warning: The ecobee4 is designed for 24 VAC systems only.

If the existing thermostat has terminals or markings indicating:

• L1/L2.
• 110 VAC.
• 120 VAC.
• 240 VAC.

The system may be incompatible.

Check compatibility before proceeding.

HVAC Control Board Warning

HVAC equipment can contain high-voltage wiring.

Power Extender Kit installation requires access to the HVAC control board.

Installation and wiring should be performed by a qualified HVAC technician.

Mercury Disposal Warning

Some older thermostats contain mercury.

If replacing a mercury-containing thermostat, dispose of the old device through a local hazardous waste facility.

Do not place mercury-containing thermostats in ordinary household waste.

Before Installation

Before removing the existing thermostat, prepare the tools, check system compatibility, and identify the wiring.

Installation Checklist

1. Confirm that the heating and cooling system uses compatible control voltage.
2. Prepare the tools and supplied installation accessories.
3. Locate the HVAC system’s master switch or circuit breaker.
4. Turn off HVAC power.
5. Verify that the equipment cannot start.
6. Remove the old thermostat cover.
7. Check for high-voltage markings.
8. Photograph the existing thermostat wiring.
9. Identify whether a C-wire is connected.
10. Select the correct installation method.

How to Check ecobee4 Compatibility

Step 1: Turn Off HVAC Power

Turn off the HVAC system using the master switch or circuit breaker.

The switch or electrical panel may be located:

• In the basement.
• In the attic.
• In a utility closet.
• Behind a wall panel near the thermostat.

Step 2: Confirm That the System Is Off

After disconnecting power:

1. Use the existing thermostat to request heating or cooling.
2. Wait a few minutes.
3. Confirm that conditioned air does not come from the vents.

For a boiler system, check that the main flame is extinguished.

Step 3: Remove the Old Thermostat Cover

Remove the old thermostat cover carefully.

Some thermostat covers snap off, while others are secured with screws.

Step 4: Check for High Voltage

Inspect the existing thermostat backplate.

Look for:

• L1 or L2 terminals.
• High-voltage warnings.
• 110 VAC, 120 VAC, or 240 VAC markings.

If these markings are present, the thermostat may be incompatible.

Check compatibility at https://www.ecobee.com/compatibility.

Step 5: Photograph the Existing Wiring

Take a clear photograph showing the wires and terminal labels.

This photograph can be used during installation.

Step 6: Check for a C-Wire

Inspect the old thermostat terminals.

If a wire is connected to C, follow the C-wire installation method.

If there is no C-wire, follow the Power Extender Kit installation method.

Choosing the Installation Method

The ecobee4 guide provides two installation paths.

Important: Both installation methods begin with the same safety and compatibility checks.

Guide 1: Installing ecobee4 With a C-Wire

When an existing C-wire is available, the ecobee4 can be installed without the Power Extender Kit.

The C-wire provides power to the thermostat.

Step 1: Label the Existing Wires

1. Confirm that HVAC power is off.
2. Use the photograph of the old thermostat wiring for reference.
3. Disconnect one wire at a time.
4. Attach the matching supplied label to each wire.
5. Continue until the thermostat wires are labeled and disconnected.

Important: If the old thermostat has a jumper between Rc, Rh, or R, leave the jumper alone. Label only the wires coming from the wall.

The ecobee4 does not require the old thermostat’s jumper wire.

Step 2: Remove the Old Thermostat Base

1. Locate the mounting screws.
2. Unscrew the old thermostat base.
3. Remove the base from the wall.
4. Keep the labeled wires accessible.

Step 3: Choose the Trim Plate

The trim plate is optional.

It can be used to cover marks or holes left by the previous thermostat.

If using the trim plate:

1. Align its mounting holes with the ecobee4 backplate.
2. Press the trim plate and backplate together.

Step 4: Mount the Backplate

1. Pull the labeled thermostat wires through the center opening.
2. Position the ecobee4 backplate against the wall.
3. Use the built-in level to align it.
4. Mark or drill the mounting holes.
5. Install the supplied drywall plugs.
6. Secure the backplate using the supplied screws.

Use a 3/16-inch drill bit for the drywall plugs.

Step 5: Connect the R Wire

Check how many R-type wires are coming from the wall.

One R Wire

If there is only one wire labeled R, Rc, or Rh, connect it to the ecobee4 Rc terminal.

Two R Wires

If separate Rc and Rh wires are present:

Step 6: Connect the Remaining Wires

Insert each remaining labeled wire into the matching terminal block.

Important: Insert wires into the side of the terminal blocks, not the front.

Press the terminal levers when needed to insert the wires.

Step 7: Check the Connections

After connecting the wires:

1. Gently pull each wire.
2. Check that it remains securely inserted.
3. Confirm that the terminal lever has lowered.

Step 8: Push Excess Wires Into the Wall

Carefully push excess wiring into the wall opening.

Make sure that drafts cannot enter through the opening.

Large openings behind the thermostat can affect temperature readings.

Step 9: Attach the Thermostat

1. Align the ecobee4 thermostat with the backplate.
2. Gently press the thermostat into place.
3. Continue until it clicks.

If the thermostat rocks or does not sit flush against the wall, check whether excess wiring is preventing proper installation.

Step 10: Restore HVAC Power

Turn the HVAC power back on using the master switch or circuit breaker.

Step 11: Complete Initial Setup

The ecobee4 should power on automatically.

Follow the instructions displayed on the thermostat to complete setup and registration.

Guide 2: Installing ecobee4 Without a C-Wire

If the existing thermostat does not have a C-wire, the included Power Extender Kit can provide a compatible power connection.

The PEK is installed between the thermostat wiring and the HVAC control board.

Power Extender Kit Requirements

The PEK requires one of the following wiring configurations.

If the existing wiring does not match these configurations, contact ecobee support before proceeding.

Important PEK Installation Warning

Warning: HVAC systems contain high-voltage wiring.

Installing the PEK requires working inside the HVAC equipment.

A qualified HVAC technician should complete this work.

Step 1: Gather the Installation Materials

Prepare:

• Power Extender Kit.
• Wire labels.
• Installation tools.
• Smartphone for reference photographs.

Go to the HVAC equipment location.

The HVAC system is commonly located in a basement or attic.

Step 2: Open the HVAC Equipment Cover

1. Confirm that HVAC power is disconnected.
2. Locate the equipment access panel.
3. Open the cover.
4. Find the HVAC control board.

Step 3: Photograph the Control Board

Take a photograph showing the control board wiring and terminal labels.

This provides a reference for restoring the correct connections.

Step 4: Label the Thermostat Wires

Identify the wires connected to:

• R.
• Y or Y1.
• G.
• W or W1, if installed.

Label only the wires running from the control board to the thermostat.

Do not label or disconnect wires running from the control board to the air-conditioning equipment unless instructed by the applicable wiring configuration.

Important: If wires are connected to both Rc and Rh at the control board, the system may use two transformers. Contact ecobee support for installation assistance.

Step 5: Disconnect the Thermostat Wires

Disconnect the labeled thermostat wires from their control board terminals.

The connection points may include:

• R.
• Y.
• G.
• W.

Step 6: Connect the Existing Wires to the PEK

Insert the disconnected thermostat wires into the matching gray terminal blocks on the Power Extender Kit.

For a supported three-wire installation, the W connection is absent.

Press the terminal buttons when needed to insert the wires.

Step 7: Check the PEK Connections

Gently pull each inserted wire.

The terminal button lowers when the wire is correctly connected.

Step 8: Connect the PEK to the HVAC Control Board

The PEK includes five white wires.

Connect these wires to their matching HVAC control board terminals.

Gently pull each connection to confirm that it is secure.

Step 9: Check the PEK Position

The Power Extender Kit should now be connected between:

• The existing thermostat wiring.
• The HVAC control board.

Check that the connections match the illustrated PEK arrangement.

Step 10: Mount the PEK

1. Position the PEK inside the HVAC cabinet.
2. Select a suitable mounting location.
3. Make sure the wires are not strained.
4. Secure the PEK.

Step 11: Close the HVAC Cover

Close the HVAC equipment cover securely.

Some HVAC systems will not operate if the cover panel is not properly closed.

Step 12: Return to the Thermostat

After installing the PEK, return to the existing wall thermostat.

Step 13: Label and Disconnect the Old Thermostat Wires

1. Use the original thermostat wiring photograph for reference.
2. Disconnect one wire at a time.
3. Label the wires according to their original terminals.
4. Leave existing jumper wires on the old thermostat.

Step 14: Remove the Old Thermostat

Unscrew the old thermostat mounting plate and remove it.

Keep the labeled wires accessible.

Step 15: Install the ecobee4 Backplate

1. Decide whether the optional trim plate is needed.
2. Align the trim plate with the backplate if using it.
3. Pull the wires through the center opening.
4. Level the backplate.
5. Secure it with the supplied drywall plugs and screws.

Use a 3/16-inch drill bit for the wall anchors.

Step 16: Relabel the Wires for PEK Installation

After the PEK has been installed, the wall wires connect to different ecobee4 terminals.

This wiring arrangement is different from a standard C-wire installation.

Step 17: Connect the PEK Thermostat Wires

Connect the relabeled wires to the corresponding thermostat terminals.

Start with:

1. Rc.
2. C.
3. PEK.

Then connect any remaining wire to its matching terminal.

For a four-wire arrangement, the original W/W1 wire connects to W1.

Step 18: Check the Connections

Gently pull each wire to confirm that it is secure.

When connected correctly, the terminal lever lowers.

Step 19: Push Excess Wires Into the Wall

Push extra wiring into the wall opening.

Prevent drafts from entering through the opening.

Step 20: Attach the Thermostat

Align the ecobee4 with the backplate and press it into position until it clicks.

Step 21: Restore HVAC Power

Turn the master switch or circuit breaker back on.

Step 22: Complete Setup

The thermostat should turn on automatically.

Follow the on-screen setup and registration instructions.

ecobee4 PEK Wiring Diagram

The PEK thermostat wiring arrangement uses the following terminal assignments.

Important: When using the PEK, the original Y wire connects to the PEK terminal, not Y1.

The original G wire connects to C.

These connections must not be confused with a normal C-wire installation.

ecobee4 Conventional Heating and Cooling Wiring

The ecobee4 supports conventional heating and cooling systems with up to two stages each.

Conventional HVAC Terminal Functions

The exact wiring arrangement depends on the installed furnace and air conditioner.

Rc and Rh Jumper

Do not connect an external jumper between Rc and Rh.

The ecobee4 handles the required connection internally.

ecobee4 Heat Pump Wiring

The ecobee4 supports compatible air-source and geothermal heat pumps with auxiliary heating.

Heat Pump Terminal Functions

Second-stage compressor and auxiliary heat connections are used when the equipment supports them.

Heat Pump Wiring Precautions

• Follow the wiring configuration for the specific heat pump.
• Connect the reversing valve to O/B where required.
• Connect auxiliary heating terminals according to the equipment.
• Do not install an external Rc/Rh jumper.
• Connect a single R wire to Rc.

Boiler and Radiant Heating Wiring

The ecobee4 supports illustrated configurations involving:

• A boiler or radiant heating system.
• An air handler.
• Conventional cooling equipment or a heat pump.

The wiring may include separate heating and cooling components.

Important Boiler Wiring Notes

• Match the wiring to the installed equipment.
• Use second-stage heating or cooling connections only when applicable.
• Use the reversing valve connection only for heat pump equipment.
• Do not connect an external jumper between Rc and Rh.
• A single R wire connects to Rc.

Humidifier and Dehumidifier Wiring

The ecobee4 can control compatible humidifiers and dehumidifiers through its accessory terminals.

The installation guide provides one-wire and two-wire connection methods.

One-Wire Accessory Setup

For a one-wire humidifier or dehumidifier connection:

1. Identify the accessory’s existing control wiring.
2. Disconnect power to the HVAC equipment.
3. Locate the accessory control.
4. Connect the accessory control wire according to the one-wire wiring diagram.
5. Use the ecobee4 ACC+ terminal.
6. During thermostat setup, select 1-wire (ACC+) accessory.

Two-Wire Accessory Setup

For a two-wire humidifier or dehumidifier:

1. Locate the accessory control.
2. Remove the existing control plate.
3. Identify the two accessory wires.
4. Connect the wires to ACC+ and ACC- according to the diagram.
5. During setup, select 2-wire (ACC+, ACC-) accessory.

Accessory Configuration Summary

Ventilator Wiring

The ecobee4 supports compatible ventilation equipment, including ERV and HRV systems.

Two-Wire Ventilator Setup

1. Locate the ventilator timer control.
2. Disconnect HVAC power.
3. Remove the existing timer control plate.
4. Identify the two control wires.
5. Connect the wires to ACC+ and ACC- according to the ventilation wiring diagram.
6. During thermostat setup, select 2-wire (ACC+, ACC-) accessory.

The illustrated ventilator arrangement uses the control terminals identified as R and G (HI/LO).

Initial ecobee4 Setup

After installation, restore HVAC power.

The thermostat should automatically power on and display the setup screen.

Setup Procedure

1. Confirm that the thermostat is firmly attached.
2. Check that the HVAC equipment cover is closed.
3. Restore power.
4. Wait for the ecobee4 display to turn on.
5. Follow the on-screen instructions.
6. Complete setup and registration.

The ecobee application can also provide customized installation instructions.

ecobee4 Home Screen and Controls

The ecobee4 touchscreen displays system information and provides access to operating controls.

Home Screen Components

How to Adjust the Temperature

1. Wake the thermostat screen.
2. Locate the temperature slider.
3. Move the slider bubble upward or downward.
4. Select the desired temperature.

System Modes

Heating and Cooling Indicators

The ecobee4 uses colors to show operating status.

ecobee4 Menu Options

The thermostat menu provides controls for system operation and scheduling.

Comfort Settings

The ecobee4 includes:

• Home.
• Away.
• Sleep.
• Custom comfort settings.

The interface supports custom comfort settings in addition to the standard options.

Quick Changes

Quick Changes provides direct access to Home and Away settings.

Weather

The Weather control displays:

• Local weather.
• Weekly weather forecast.

ecobee4 Voice Control

The thermostat includes a voice control interface.

Voice Control Options

Adjusting Voice Volume

1. Open the Voice Control interface.
2. Locate the volume controls.
3. Adjust the volume.

Turning the Microphone Off

Use the microphone control to disable the microphone.

The interface displays a Microphone Off indicator when the microphone is disabled.

Room Sensor

The ecobee4 includes a separate room sensor and stand.

The room sensor is supplied with its own instructions.

The thermostat installation package includes:

• Room sensor.
• Room sensor stand.
• Room sensor manual.

Follow the supplied room sensor instructions for installation and pairing.

ecobee4 Troubleshooting Guide

The installation guide provides checks for thermostats that do not turn on after installation.

ecobee4 Not Turning On

If the thermostat does not turn on after installation, begin with the wiring and equipment cover checks.

Check Thermostat Wires

1. Turn off HVAC power before touching the wiring.
2. Check that every wire is inserted into the correct terminal.
3. Gently pull each wire to confirm it is secure.
4. Reinsert any loose wires.
5. Confirm that the terminal levers have lowered.

Check the HVAC Cover Panel

Some HVAC systems include a safety switch that disconnects power when the equipment cover is open.

Make sure the HVAC cover panel is securely closed.

Check the R Wire

If the installation has only one R-type wire, it must be connected to Rc.

This applies to a wire originally labeled:

• R.
• Rc.
• Rh.

Check PEK Wiring

If the Power Extender Kit was installed, confirm the following connections:

Check that the PEK itself is correctly connected to the HVAC control board.

If the thermostat still does not turn on, contact ecobee support.

ecobee4 Power Extender Kit Not Working

If the thermostat does not power on after PEK installation:

1. Confirm that the HVAC power supply is available.
2. Turn off power before checking connections.
3. Check the five PEK wires at the control board.
4. Check the original thermostat wires connected to the PEK.
5. Confirm that the wall’s R wire connects to Rc.
6. Confirm that the original G wire connects to C.
7. Confirm that the original Y wire connects to PEK.
8. Check that the HVAC access panel is properly closed.

Contact ecobee support if the correct connections cannot be confirmed.

ecobee4 Not Sitting Flush Against the Wall

If the thermostat rocks or does not sit against the backplate:

1. Remove the thermostat from the backplate.
2. Check for excess wires behind the thermostat.
3. Push the excess wires back into the wall opening.
4. Reattach the thermostat until it clicks.

Turn off HVAC power before disturbing wiring.

ecobee4 Temperature Reading Problems

Large openings behind the thermostat can allow drafts to affect temperature readings.

Make sure the wires are pushed back into the wall opening and that drafts cannot enter through it.

FCC and Regulatory Information

The ecobee4 complies with applicable radio-frequency equipment regulations.

FCC Compliance

The device complies with Part 15 of the FCC Rules.

Operation is subject to two conditions:

1. The device must not cause harmful interference.
2. The device must accept received interference, including interference that may cause unwanted operation.

Radio or Television Interference

If the ecobee4 causes interference:

• Reorient or relocate the receiving antenna.
• Increase separation between the thermostat and receiver.
• Connect the affected equipment to a different electrical circuit.
• Consult an experienced radio or television technician.

RF Exposure Requirements

Maintain at least 8 inches (20 cm) between the transmitter and people during normal operation.

Regulatory Identifiers

Unauthorized Modifications

Changes or modifications not expressly approved by ecobee may void the user’s authority to operate the equipment.

Apple HomeKit Information

The ecobee4 legal information includes Apple HomeKit certification language.

Apple HomeKit accessories are designed to connect with supported Apple devices.

Apple is not responsible for the operation of the accessory or its compliance with safety and regulatory standards.

Using the accessory with an Apple device may affect wireless performance.

Warranty Information

The ecobee4 includes a three-year limited warranty covering qualifying defects in materials and workmanship.

Warranty Coverage

Warranty Eligibility

The warranty applies to qualifying products used and maintained under normal conditions.

It is valid only for products installed in the country where they were purchased.

Warranty Service

If the thermostat develops a covered defect during the warranty period, ecobee may repair or replace it.

A repaired or replacement device remains covered for the longer of:

• The remaining original warranty period.
• 90 days.

How to Request Warranty Service

1. Contact ecobee Customer Service at 1-877-932-6233.
2. Explain the problem.
3. Provide proof of purchase when requested.
4. Follow the warranty service instructions.

ecobee determines whether the unit can be replaced or must be returned.

Warranty Service Through a Contractor

If the thermostat was purchased through a third-party contractor, the customer may contact that contractor about obtaining an equivalent replacement.

The contractor must determine that the product is defective and that the customer qualifies for warranty service.

Advanced Replacement

ecobee may provide an equivalent replacement before receiving the defective thermostat.

A temporary credit card hold may be required until ecobee receives the returned product.

Warranty Exclusions

The warranty does not cover removal or reinstallation costs.

It also excludes damage caused by:

• Abnormal operating or storage conditions.
• Improper maintenance.
• Unauthorized repair or modification.
• Abuse or neglect.
• Electrical faults.
• Improper handling.
• Accidents.
• Natural events.
• Incorrect installation.
• Installation not performed by a licensed HVAC contractor.

Important: The warranty excludes a thermostat that was not installed by a licensed Heating, Ventilating, and Air Conditioning contractor.

Warranty Limitations

ecobee limits its responsibility for qualifying defects to repair or replacement under the stated warranty.

Additional legal rights may vary by jurisdiction.

Customer Support Information

ecobee provides technical support for thermostat installation and operation.

When to Contact ecobee Support

Contact ecobee for assistance with:

• HVAC compatibility.
• Unfamiliar thermostat wiring.
• Two-transformer systems.
• Power Extender Kit installation.
• Thermostat startup problems.
• Incorrect or uncertain terminal connections.
• Warranty service.

Frequently Asked Questions

How do I install the ecobee4 smart thermostat?

Turn off HVAC power, remove the old thermostat cover, and photograph the existing wiring. Check for a C-wire. If a C-wire is present, mount the ecobee4 backplate and connect the labeled wires. If there is no C-wire, install the Power Extender Kit using the supported HVAC wiring arrangement. Attach the thermostat, restore power, and follow the on-screen setup instructions.

Does the ecobee4 require a C-wire?

The ecobee4 requires a compatible continuous power connection. An existing C-wire can provide this connection. For certain systems without a C-wire, the included Power Extender Kit allows the thermostat to be installed using supported three-wire or four-wire configurations.

How do I wire the ecobee4 with the Power Extender Kit?

Install the PEK between the HVAC control board and existing thermostat wiring. At the ecobee4 thermostat, connect the original R/Rc/Rh wire to Rc, G to C, and Y to PEK. If a W/W1 wire is present, connect it to W1. HVAC power must be disconnected, and the work should be performed by a qualified technician.

Why is my ecobee4 thermostat not turning on?

Check that the thermostat wires are securely connected, the HVAC cover panel is closed, and a single R wire is inserted into Rc. If the PEK is installed, confirm that Rc, C, and PEK connections match the installation diagram. Contact ecobee support if the thermostat still does not power on.

Can the ecobee4 control a heat pump?

Yes. The ecobee4 supports compatible air-source and geothermal heat pumps with auxiliary heating. The wiring diagrams include compressor connections, the O/B reversing valve, and auxiliary heating terminals where required.

Can I connect a humidifier or dehumidifier to the ecobee4?

Yes. The ecobee4 supports compatible humidifiers and dehumidifiers through its accessory terminals. The installation guide provides one-wire ACC+ and two-wire ACC+/ACC- wiring methods. The correct accessory type must also be selected during thermostat setup.

How do I adjust the temperature on the ecobee4?

Wake the thermostat screen and use the temperature slider. Move the slider bubble upward or downward to select the preferred temperature. The home screen displays the current indoor temperature and system mode.