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Help! Why Is Ecobee Not Cooling or Heating? What You Can Check

Cold Man and Blown AC

The heating and cooling systems in our homes can be pretty complicated systems, and unfortunately, it’s not uncommon for them to stop working for whatever reason. There are lots of safety sensors and parts and every one of them has to work just right.

Calling a repair man can be expensive, costing around $70 just to have them come to your house. That’s part of the reason why when something stops working, I often like to see if I can fix it myself first.

However, I just want to point out that HVAC parts are usually only sold to contractors, and not the general public. If you do find a store that sells parts to the public, keep in mind that they do not usually have return policies like the big retailers. If you buy something, you may not have a way to return it.

Ecobee, just like all other thermostats, only tells the equipment when to start and stop. The temperature of the air, whether hot or cold, depends on the equipment.  Your Ecobee is fine, unless your Ecobee is programmed wrong or wired up wrong and makes both furnace and AC run at the same time.

Let’s take a look at the top reasons for failures, and some details on how to fix each problem. These failures assume that your Ecobee was previously working, and then stopped.

Reasons why Ecobee is not Heating.


I don’t mind being a little cold when I’m outside, but I really don’t like being cold when I’m at home. Here are the most common reasons why Ecobee is failing to heat your house.

Ecobee And/or Furnace are not powered

The Ecobee receives power from the furnace, so if it’s not powered, then your furnace is not powered. Ecobee thermostats need 24VAC constant power supply from the furnace in order to work correctly. If your Ecobee thermostat has powered off it is likely not receiving any power from your furnace. You can pull the Ecobee off the wall and use a DMM or voltmeter to check the voltage across the Rc and C terminals. Likewise, if your Ecobee thermostat is rebooting frequently, the furnace is also a likely culprit.

If you need help on how to remove your Ecobee thermostat, check out my article here on how to uninstall an Ecobeef.

Ecobee doesn’t have batteries, so you can’t use the thermostat to test if your furnace has power. In the old days, before smart thermostats, you could use your thermostat to turn the furnace “on” instead of “auto.” If the furnace’s fan came on, then you would know the furnace has power. If not, it lacks power. If you still have your old thermostat, you could connect it back up and try it, but that is a lot of work.

Check the Circuit Breaker for the Furnace

Since using Ecobee to check furnace power isn’t an option, start by checking the circuit breaker. If the circuit breaker is tripped, reset it by and turn it back on. You may have to turn it all the way off, and then back on. You should hear a click, and in the end, it should be aligned like all the other breakers. If the breaker was tripped, wait five minutes and then the furnace should turn back on. Most thermostats have some sort of time delay built-in.

Check the Power Switch for the Furnace

At the furnace, there should be a switch to control power. It will look like just like a light switch. These occasionally get turned off accidentally, like when someone is moving boxes around in the attic.

If none of this has worked so far, the power switch is on and the furnace still lacks power, then it is time to check the furnace’s main and secondary electrical panels.

First, turn off power to the furnace at the circuit breaker. You don’t want to get shocked.

Next open up the furnace and look for a reset button that has popped up. Push it back in, get everything put back together, and then turn the power back on. The furnace should start within five minutes.

Still not working? It’s probably time to call in a professional.

As a note, it is important to know what is causing the circuits breakers to cut power. Breakers trip, or fuses blow, when there is too much current being drawn. This protects other equipment in that circuit, and also helps prevent house fires. These surges can damage electronics and appliances which may end up costing thousands of dollars in damage.

Even if nothing seems damaged the first time, that doesn’t mean everything will be find the second time, or the next time. Make sure you fix the problem. If your circuit breaker trips or fuse box blows a fuse again and you can’t figure out why, call a qualified electrician to address the problem.

Furnace Overheating

All furnaces contain a temperature sensor on the inside which is used as a safety mechanism. If your furnace ever overheats, this sensor will trigger the furnace to turn off, and therefore the heat will turn off. Depending on which model you have, the furnace may continue to run the fan blower to help cool itself off, or it may shut down completely until the system has been reset or has cooled down to a safe level.

Reduced or Restricted Airflow

If you ever had an HVAC person out to your house, no doubt that they’ve told you to replace your air filters. This is one of the reasons why. If air is is not able to circulate properly throughout your HVAC system, it can cause your furnace to overheat. And you guessed it, the most common cause of restricted airflow is a dirty air filter.

That is why you should remember to at least check your air filter, and change it as needed throughout the winter season (also applies to summer when you’re using the A/C). A lot of professionals recommend checking your filter at monthly and replacing it when you start to see dust.

Check that the air grills that hold the air filters in place are clean as well. I personally check mine every three months or so, and clean them once or twice a year. It’s not hard to just take a look up when you’re walking under one to see how dirty it is.

Dirty Components

If you have been slacking on changing your air filters, the furnace’s internal components, such as the blower wheel, can also start to get some dust and dirt build up. Those two components can prevent the furnace heat exchanger from putting the heat in the airstream, causing it the furnace to overheat.

Short Cycling

Short cycling is when a furnace turns off too soon in the heating cycle. It’s okay if this happens occasionally, but when this happens repeatedly the furnace heat exchanger and blower motor become stressed, leading to overheating. If the issue is ignored than burning out the motor entirely is possible, or failure of the heat exchanger. If short cycling is happening, call in a HVAC professional to get it fixed before it ends up costing you more money.

Component Failure

The lifespan of a HVAC system is somewhere around 15-20 years, assuming it was properly maintained. There are a lot of components, from electrical wiring to the fan blower to the motor. These furnace components will fail over time. When properly maintained with annual inspections and maintenance, you can avoid costly repairs and get the most longevity out of your HVAC system.

Ecobee is not turning on heat

Your ecobee thermostat will display an orange-colored flame icon when heating is turned. If the outline on the flame icon is white, the thermostat is not calling for heat.

Ecobee Heating
Example of Ecobee with Heat turned on

Check the Ecobee Heat Setting (Heat Set Point)

This item is lower on the list because it is a less common reason for “failure”, even though it may seem obvious and is probably the first thing you should check if Ecobee isn’t turning on the heat. What is the “heat set point” set to? Set Point is the industry term for the temperature you have set your thermostat to maintain. Therefore, Heat set point is the coldest temperature your thermostat should allow. It should be higher at least 1 degree higher than the current temperature in the house if you expect the heat to turn on.

Changing the heat set point can easily be done on the from the Ecobee or in the Ecobee app or web interface.

First, make sure your thermostat is set to Heat or Auto mode. You can tell the which mode Ecobee is set to by looking at icons above the temperature and humidity. Snow flake indicates cooling, flame indicates heating, both snow flake and flame indicate auto mode (most common), and nothing means HVAC mode is set to off.

HVAC mode can be changed by going into the main menu (bottom left button in the screenshot above), and then clicking the HVAC mode option and selecting the mode you desire. I recommend auto because it will allow Ecobee to control when the AC or Heat needs to come on.

Use the slider on the main display screen to increase or decrease the desired temperature. You will see the set point temperature displayed in the circle you moved, as well as in a white box under the current temperature reading. The orange circle is the desired temperature for heat, and the blue circle is for cooling.

On the main screen, you can use the slider to adjust the temperature to where you want it.

You can see all the parts I’m talking about in the screenshot at the beginning of this section that I took. I intentionally left the image big to make it easy to find these various parts.

Adjust the Thermostat Settings

One of the reasons I like Ecobee is because it gives users a lot of control over their thermostat. It’s highly customizable, and you can get exactly what you want, for the most part. Side Note: That’s also one of the reasons I like Android more than Apple.

One example of customization is being able to change the temperature differential. That means the minimum difference between the current temperature and the set point required to turn on the heater (or cooling).

There are some settings that can only be done on the Ecobee unit itself, and this is one of them. Changing the temperature differential cannot be done using the Ecobee app or website.

Here is how to adjust the heat threshold settings on the Ecobee unit:

    From the main menu, select “Settings.”

    Select “Installation Settings.”

    Select “Thresholds.”

Ecobee Main Menu
Ecobee Main Menu. HVAC mode is second options

Lowering the heat differential temperature will cause your heater to turn on sooner, while Raising it will allow the house to get cooler and therefore not turn on the heat as soon. The default differential is half a degree, or 0.5.

Reasons why Ecobee is not Cooling.

Sparking A/C

Hopeffully your A/C unit isn’t blowing out sparks like this. Here are the most common reasons why Ecobee is failing to cool your house.

Condensation problems in the air conditioner

The most common cause of your air conditioner not turning on is an excessive build-up of water from condensation within your HVAC system.

leaking drain pan
Example of leaking drain pan

Your HVAC system has a drain pan or drain line. Now you know what it is if you’ve ever seen a pipe sticking out the side of your house, occasionally dripping water. Over time, mold, algae, and dirt can build up inside these pipes and pans. Add to it that dirt tends to stick to water, which causes build up to happen faster. A safety device will trigger if the water level gets too high. When triggered, power to the thermostat and air conditioner will be cut off.

There are several reasons why the water in the drain pan may begin to build up.

  • the line can get knocked out of place,
  • bacterial growth might clog the drain, or
  • dust and dirt build up.

When build up occurs, the shallow drain pan, which are about 2 inches deep, will start to overflow and spill out into your home.

Just like a roof leak, this will cause is water damage. These leaks are often not noticed for some time since they are often placed in the attic out of site. The water damage can become severe and lead to thousands of dollars in repairs on top of the HVAC repairs that are needed. This is one reason I recommend having routine maintenance done annually. A serviceman should notice if there appears to be water damage, and should at a minimum tell you. They will usually offer to fix it for some fee.

The leaking water can lead to other dangerous and damaging conditions. The standing water will cause mold to grow, which will warp your homes wood frame, ruin drywall, as well as release mold spores into the air inside your home. Mold spores effect some people more than others, but in any case, you don’t want them in your home.

HVAC professionals will advise you to NOT try and repair the problems yourself. They warn that a mistaken fix can end up causing additional leaking, resulting in more costly and prolonged damage. However, I take their advice with a grain of salt. Clearing a clogged pipe isn’t that complicated. If you’re unsure what the problem is, than I would recommend contacting the pros.

Ecobee is Not Configured Properly for Cooling

Just like I said for heating, one reason why your Ecobee would not turn your air conditioner on is that it is not set up to turn the A/C on.

Here are the directions to adjust the cooling threshold settings:

    From the main menu, select “Settings.”

    Select “Installation Settings.”

    Select “Thresholds.”

Since the air conditioner has components that are outside, there are a few more settings that you can adjust while in the settings menu.

Compressor Minimum Outdoor Temperature.

When the outdoor temperature is below this minimum threshold, Ecobee will not run the compressor. You can check the main screen on Ecobee to see what it thinks the temperature is outside. If the location is not correct, go ahead and fix that by setting the correct location. If you do adjust the temperature setting, keep in mind that is there as a protection for the equipment. Make sure to read the specifications for the compressor before adjusting.

Compressor Minimum Cycle Off Time.

This is the minimum amount of time that the compressor must remain off between on cycles. By default, this is set to 300 seconds (5 minutes). If your Ecobee has completed a cooling cycle, it will wait at least the minimum amount of time before turning the compressor on again. Again, make sure to read the specifications for the compressor before adjusting.

Contact Ecobee Support First before an HVAC Professional

If you are an Ecobee customer, they provide free support. So, unless you have an HVAC emergency, I’d recommend contacting Ecobee first to try and get your issues resolved. Having HVAC service people out to your house is not cheap. It cost them time and money, which they pass on to you. They’re a business, so I don’t blame them, but even a simple fix could end up costing you over $100.

The latest information for Ecobee support can be found on their support website here. They have phone, chat, e-mail and twitter as support options if you can’t find the answer on their support page.

I know this article has been about fixing Ecobee problems, but if you would like to know more about why I still recommend Ecobee, check out my recommendation page here.