Why Is Ecobee Thermostat Temperature Not Going Down? 4 Common Causes & Solutions

Ecobee thermostats are famous for their smart home integration, allowing users more control over their air conditioning systems and allowing them to save energy. Modern solutions come with age-old problems – you might find that your thermostat is not behaving how it should.

An Ecobee thermostat may not cool for several reasons, such as incorrect settings, system faults, or an incorrect installation. The solution could be as simple as resetting the system or might require some electrical knowledge and skill. Checking the manual is always a good place to start.

If you aren’t ready to throw in the towel and call in an expert, I’ve put together a few tips on how to solve your Ecobee woes below. Remember that electrical work can be dangerous and should not be attempted by unqualified individuals.

1. Your Ecobee Has No Power

One of the easiest things to check on your Ecobee if it isn’t cooling is whether it has power in the first place. Adapters should be firmly plugged in and powered, there should be no loose wires, and the unit should power up.

Electrical problems include faulty adapters, poor, broken, or incorrect wiring, and insufficient power. 

The next port of call is the fuses integrated into the unit to prevent damage from electrical faults. Electrical surges, lightning strikes, or faulty wiring can cause a fuse to blow. 

The colors may not be standardized. Poorly marked wires can take time to figure out – it may be best to call an expert if this is your situation.

You can also engage your sense of smell here. Burning electrics have a distinctive metallic smell, often intermingled with the musk of overheated insulation. You might even see burn marks. Be sure to turn off any power to your HVAC system before checking or handling wires.

How To Fix?

If your Ecobee isn’t turning on, verify that its wires or adapters are correctly connected. 

Your user manual will contain installation instructions to help you verify if the Ecobee has been installed correctly. You could replace the adaptor or tighten any loose connections you find.

The Ecobee unit itself may be faulty. However, I’d advise calling in an expert if you suspect electrical faults, unless you have the expertise yourself. The danger of tampering with electrical systems cannot be understated. 

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That said, don’t automatically assume that you have an electrical fault. It could be something else entirely. 

Read: Why Ecobee Thermostat Not Turning On AC? – Troubleshooting Guide

2. Your Ecobee Is Set Up Incorrectly

We’ve all been there – a new and convenient technology begins misbehaving. Eventually, we find that it isn’t the technology but our lack of knowledge causing us to misuse it.

The user’s manual is an invaluable resource even if you’ve had your Ecobee for a while. It’s good practice to hang on to this kind of thing – I keep mine manuals in the item’s box. If you don’t save boxes like me, store the manual amongst other books.

It contains lots of information about correctly installing your Ecobee and troubleshooting the system. If you haven’t, take some time to familiarize yourself with the documentation supplied with your unit. This is a useful habit to develop if you enjoy electronics.

How To Fix?

Referring to your manual, you can learn how to correctly set the temperatures on your Ecobee thermostat. The system may have reverted to a pre-set scheduled temperature, preventing it from cooling the way you prefer. You can change this either through the app or on the device directly.

Understanding a system is always the first step in troubleshooting it. Carefully read your manual to understand the Ecobee system. This will arm you with knowledge for future problems and point you in the right direction to solving the current one. 

The Ecobee can alert you to problems in the system, such as filter blockages. You can also find information to set up your own temperature schedules. Alternatively, you can set Ecobee up to alert you when it detects that nobody is home so you can turn off the system and save energy.

If all else fails, resetting your Ecobee might be the way to go. Refreshing your settings might do the trick – it could be as simple as setting the thermostat to maintain a lower temperature. You could also find yourself with other problems, so save the reset as a last resort if possible.

Read: How To Fix Ecobee Alexa Not Responding?

3. The System Is Blocked

A poorly functioning cooling system may have nothing to do with the thermostat itself. The system appears to have power, and your settings look good – but you’re still feeling a bit hot under the collar. What gives?

Before calling in the experts, check the cooling system’s components and carefully inspect them for obstructions.

Once again, safety comes first – the system should be off at the main circuit breakers, with no power available while you’re working on it.

How To Fix?

Since these systems are generally as individual as the homes they are installed in, there is no one-size-fits-all fix here. 

Check any filters or screens that may have become clogged up with dust, restricting airflow. Fans can also build up a surprising amount of gunk over time, even if there are filters in the system.

Ecobee can warn you to clean your filters, but the feature doesn’t work out of the box. When in doubt, it’s best to rule out all possibilities. You wouldn’t want to call the HVAC guy and be embarrassed when he shows you how dirty the filter you didn’t check is!

Radiators and filters can get clogged up easily. Filters can either be cleaned or replaced, while radiator cooling pipes and fins should be free of dust and debris. Clean a dirty radiator gently using brushes and water, being careful not to damage anything.

Homes with pets are especially prone to blockages. If you’re an animal lover and you haven’t cleaned out your cooling system lately, this is an excellent place to start. Pet hair can wreak havoc in systems with moving parts, causing heat, friction, and even component failure.

Read: 4 Reasons Why Ecobee Thermostat Fan Keeps Running

4. Your System Is Incompatible With Ecobee

Ecobee is a versatile and intelligent system to have in your home. The prospect of using this device to control your air conditioning and save energy and money makes it a worthwhile investment, especially if you are climate conscious.

Unfortunately, given the wide variety of HVAC systems, Ecobee may not be compatible with the one in your home. While Ecobee works with most HVAC systems, there are a few exceptions.

Ecobee thermostats work with most 24-volt systems. So, if you have a high-voltage system (visually identifiable by the thicker wires, larger nuts, and hopefully also marked accordingly for safety), you may be out of luck.

Read: 3 Reasons Why Ecobee Thermostat Is Overheating

How To Fix?

Don’t give up on your dreams just yet! While you may not be equipped to solve the problem of an incompatible system, contacting a professional might yield the desired results. 

You can run through this official compatibility checker to determine whether or not you can use the Ecobee with your system.

If you have a high-voltage system, you could get a step-down transformer installed, enabling you to use it with the Ecobee. Again, don’t attempt this yourself if you don’t know what you are doing – high voltage systems are hazardous.

Unfortunately, some systems will not work with your Ecobee thermostat. Examples of systems that will not work are proprietary systems (usually identifiable by the unusual wire labels), DC systems, millivolt systems, and solid fuel systems. 

Read: No Power To The Home Temperature Thermostat – Troubleshooting Guide


It’s always worth trying your hand at solving your own problems. Often, a little understanding and effort will save you the money you might otherwise spend calling in experts. 

Sometimes, the problem is simpler than we think. Don’t spend your hard-earned money calling someone out if they are only going to clean a filter, charging you labor.

I would like to reiterate that one should always be aware of their own limitations. Always consult an expert if you don’t have experience working with electricity and wiring – it could cost you your life otherwise!