Ecobee not turning on AC: finding the perfect solution

Even though it’s really annoying when your air conditioner cooling systems break down, it’s not always necessary to replace them. Sometimes the solution is actually fairly easy.

You have come to the right place if your Ecobee turn on the AC.

Ecobee not turning on AC: Best finding the perfect solution

Why is the AC not kicking on?

A significant accumulation of water from condensation within your HVAC system is the most frequent reason for your air conditioner cooling system not starting.

Why is ecobee not cooling?

The ecobee should be functional unless there is a hardware issue with your AC. We’ll go over any ecobee-related issues as well as further hardware troubleshooting advice.

It’s possible that your air conditioning system itself is the issue and not your ecobee thermostat. We’ll go over several actions you can do to restart a broken air conditioning system.

You can use these procedures to troubleshoot your ecobee if it’s not cooling to the desired temperature. Here, the issues could overlap.

Why is my ecobee not turning on my AC?

Your air conditioner should ideally start on its own after Ecobee is installed. You might find, though, that things don’t go as to plan. The good news is that the situation is easily fixed despite being an unfortunate affair.

These are the primary reasons why the AC in your Ecobee won’t switch on:  drain obstruction brought on by condensation from the HVAC system;  low levels of refrigerant;  the air filters in the air conditioner that are clogged; the AC capacitor may no longer be functional; a dormant fan.

Moreover, your Ecobee thermostat can be defective or with incorrect installation parameters. Your air handler unit’s failure to operate could be due to a variety of different factors.

Causes for your AC not being turned on by ecobee

The ecobee doesn’t switch on the AC for essentially two reasons. When the HVAC system is operating, some water from the surroundings condenses, which is significant initially. It’s possible for the HVAC system to get plugged with moisture and stop working as a result.

Clogged drain line

A drain pipe or pan will be present in every HVAC system. The HVAC system also deals with moist and dusty air. Algae, mold, or dust may grow as this air circulates through the system and clog the drain tube or pan.

As a result, a buildup of condensing water will be caused by the deposit of these items.

When the water accumulation reaches a certain point, the safety device for the system turns on. The thermostat and conditioning  will then lose electricity, making it impossible for them to activate when necessary.

You can rapidly tell if you have a clog by watching out for the development of the following warning signs.

Your ecobee thermostat must be on when it should be off, therefore if a drain is plugged, that should be a warning indicator. If the Ecobee thermostat keeps restarting itself, it’s also possible that there is a drain obstruction.

Furthermore, when there is a blockage, you will surely notice water pools or spills from the condensate drain line or AC drain pan. It’s not required to see large bodies of water. Even the presence of moisture in an area near the air conditioner indicates that the drain pan is clogged.

If your drain pan is overflowing, it is unquestionably clogged. If it fills up quickly, there’s another sign that the condensate drain line or drain pan is clogged.

Not to mention, look out for water damage near the drain pan.

If you find either of these, your next step should be analysis to identify the blockage of your condensate drain line or drain pan. Before beginning the investigation into a drain pan clog, take care to shut off the power supply to the HVAC. You should also shut off your air handler, compressor outside, and furnace.

Here are the symptoms of and solutions for a blocked HVAC drain line or drain pan.

Determine the position of important parts

The location of the Drain Pan and Drain line must be determined. Determine the location of the evaporator coils as well. Your system’s model will determine where they are located.

The first thing to do is to locate the drain pans and evaporator coils. In some systems, they could be on the furnace’s top or bottom or the air handler’s top or bottom. They might also be at the side or towards the base.

Find the drain line next. It frequently appears on the furnace’s side. It is easily recognized because it is often a PVC pipe. Although it might be any hue, the majority of systems use white.

Be aware that your HVAC system may have two drain pans rather than one under the evaporator coil. If it’s in the attic, then such a thing could happen. The primary pan in this situation is often found directly beneath the evaporator coil. The other serves as a backup. Usually, it’s below the air handler.

Remove the clog

The next step is to drain the parts if you discover that they are clogged. Sediments could be obstructing the drain pipe. Thus, you must use a powerful water jet to rinse the dirt away. Depending on the severity of the clog, you might not need to use water, but you’ll need to decide what to use.

Consult an HVAC specialist for advice if you are unsure of how to do the cleaning. As an alternative, look at some of the do-it-yourself HVAC cleaning instructions from professionals on web resources.

You’ll discover that unclogging the drainpipe is a simple task that doesn’t need professional assistance. The solution should be as simple as running some water through the system.

Float switch reset

The float switch needs to be reset last. It is often located at the side of the drain pan in HVAC systems. It might also be at the furnace’s or air handler’s bottom. If you look at these areas, finding it ought to be simple. You might not be finding it, though. Consult the air handler’s or the furnace’s control board in that situation.

The float switch will often be wired to the “R” terminal. Follow this wire from the “R” terminal to where it finishes if you’re still having trouble finding the reset switch.

The next step is to reset it once you’ve located it. Drain the water from the pan first. As an alternative, you can decide to wait for the water to drain naturally.

There are several ACs that lack a reset button. In such a situation, take a moment to relax by first turning the thermostat off for the air conditioner. Turn it off for about five minutes, after which you should turn it back on. The AC will be reset by the action.

Consult an HVAC specialist if you are still unable to reset the AC using this method.

Low levels of refrigerant

Insufficient refrigerant will prevent your air conditioner from turning on when it’s needed. Typically, the cooling substance keeps the coils from overheating. You will struggle to use the AC to produce cool air at low settings. Additionally, it inhibits the AC’s capacity to distribute hot air from the heat pump.

As a result, a refrigerant is one of the crucial components of an AC which is functioning properly. Be mindful that the AC won’t totally exhaust the refrigerant. Low levels could alternatively be the result of loss due to leakage

Frequent breaks in the AC coils allow refrigerant to leak through. Lack of routine maintenance frequently leads to coil corrosion. Routine inspections are crucial to discover leaks and fix them because it will take time for them to deteriorate.

Additionally, take into consideration that fixing the issue can require the help of a specialist. You could consider adding refrigerant, although it will be challenging to match the amounts advised by the manufacturer. For the best results, therefore, visit an HVAC specialist. They will investigate the source of the leaks and make recommendations for the best way to proceed.

Obstructed air filters

Many individuals don’t regularly clean their air conditioners’ filters, which is probably why they break down. The type of air filters you are using is irrelevant. It is essential to clean them frequently. If not, you’ll breathe contaminated air, which will eventually cause the AC to malfunction.

Filters that are frequently blocked will also damage your exterior AC unit. Frequent freezing of the AC prevents optimal operation and finally results in failure.

Why does this happen? The root of all this is, of course, the refrigerant. When filters are obstructed, the refrigerant is unable to receive warm air from your home’s interior. The outcome will be that it will eventually become cold and freeze.

Because there is little assembly necessary, the air filters are easy to clean. Instead, you might engage a professional to thoroughly clean them. Remember that the ice will be melting in coils as you clean them. Create a mechanism to collect this water, then. Don’t forget to provide enough time for the filters to dry.

Regularly checking the air filters is necessary to identify clogging and take immediate corrective action.

A defective AC capacitor

Check to see if the AC turns on and off quickly. Additionally, you might discover that it is difficult to start or that it makes strange clicking noises. These are all indicators that the AC capacitor may be dead.

One of the important parts of an air conditioner is the capacitor. It is essential to the motor circuit’s operation, particularly during the initial stages of turning on the motor. The capacitor stops regulating the circuit once it is in operation.

There are two major capacitors in every HVAC system. The AC motor’s start-up phase benefits from the presence of a start capacitor, which comes first. The run capacitor, on the other hand, keeps the motors going continuously.

Failures of capacitors can have a variety of causes. Let’s examine each of them in more detail.

Heat sensitivity

Normally, overheating will have a significant impact on the capacitor. The capacitor will heat up as a result of the AC overworking itself frequently to control the temperature in the immediate area.

If a capacitor is left out in the open, it may also overheat from exposure to the sun.

By not overworking the AC, you can prevent the capacitor from overheating. For instance, avoid adjusting the thermostat’s settings to the extremes when it’s hot or freezing outside. This causes the capacitor to operate excessively. As a result, it overheats and quickly degrades.

Fluctuations in power

Power sags or outages happen frequently anywhere. However, they are the main reasons why the HVAC’s capacitors get damaged. By incorporating a surge protector into the circuit, you can resolve this problem.

A dated capacitor

It’s also possible that the capacitor wore out over time. In order to determine whether the capacitor is wearing out, routine maintenance is essential. Replace it if it begins to exhibit any indications of aging or functioning slowly.

Make sure you are confident in the replacement of the capacitor. Consult an electrician if you lack the necessary experience; otherwise, you risk electrocution. Additionally, make sure you always have a proper AC capacitor.

The motor will be damaged if you use one that doesn’t match the good rating. The cost of replacing the motor is high. You would therefore want to have the proper capacitor.

A dormant fan

Your fan can be at blame if your AC won’t turn on. You might discover the fan is frequently broken. The most likely explanation is that it is dormant. The possibility that the air conditioning system is inactive over the winter is another potential problem. Of course, you don’t need to chill your home at this time.

As a result, the fan was presumably idle the entire time and could now not rotate as a result of the buildup of particles. If the fan has a problem or you can’t get it to run again, an HVAC specialist will help you fix it.

Solutions for ecobee thermostat problems

This part focuses on potential problems with the ecobee thermostat itself, as opposed to the preceding section which concentrated on your HVAC/air conditioning system.

Check the ecobee thermostat wiring

Starting with the ecobee thermostat wiring, we’ll examine any potential thermostat wiring concerns. The AC could easily not start due to loose thermostat wire bundle connections.

Take the thermostat out of the wall-mounted housing. Now the thermostat wiring will be visible.

The “Y” wire has to be thoroughly inspected. This wire is in charge of turning on the external air conditioning compressor. Pull gently on this wire to make sure it is connected properly.

Ensure that no wires are inserted into the incorrect terminals. You can consult the thermostat installation wiring schematics on the ecobee website if you’re having trouble with the wiring.

Check your furnace or air handler wiring

The next step is to verify the wiring at your HVAC furnace or air handler control board once you’ve made sure the thermostat wire is in perfect working order.

Again, the “Y” wire is crucial in this situation. Verify that it is the same “Y” wire that is attached to your thermostat and that it has been correctly terminated. The “Y” wire’s wire splices should also be thoroughly inspected if there are any.

Two distinct wires should also be flowing from the external compressor. This furnace or air handler wires should be attached, one to the “Y” terminal and the other to the “C” terminal. Verify the tight fit of each of these wires.

Check your settings

The next step is to inspect the equipment’s configuration if you are satisfied that the wiring is in perfect condition.

Use the Ecobee app or the thermostat’s menu to get to the next section and check the configuration.

Configuration -> Installation Equipment -> Wiring -> Settings

The RC and RH should both be emphasized. If the thermostat’s RC terminal only shows one wire connected, the thermostat needs to be reconfigured.

Verify the threshold settings

Go to the next section with the app’s installation settings.

Settings -> Installation Settings -> Thresholds

You need to double-check a few options in the threshold settings.

Compressor minimum outdoor temperature

If the outside temperature is below than minimum outdoor temperature, the outdoor compressor unit will not operate. Lower the temperature of the outdoor compressor unit if necessary.

Compressor minimum cycle Off Time

The minimum compressor cooling cycle time in cooling mode is set by default to five minutes (300 Seconds). Your compressor won’t turn on until the specified amount of time has passed if it has already finished a cycle.


When the AC isn’t turned on by your Ecobee thermostat, it is annoying. Thankfully, though, this problem is frequently brought on by a full drain pan, which is easily avoidable.

Make sure the HVAC system is functioning properly first. Your issue is most likely an excessive amount of water build-up inside the unit.

If you’re still experiencing problems after cleaning the drain pan, you can troubleshoot your Ecobee. Verify the security of all wiring. Then, after reconfiguring the apparatus, check the installation settings and change the threshold settings as necessary.

Robert Brooks

I have an engineering background. I have my own house, where I live with my wife and children. I want to say that the most important thing when equipping a house is to choose the right heating, ventilation, and air conditioning systems.

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