Why Carrier Thermostat Blinking Cool ON? – Troubleshooting Guide

We are used to thinking that any blinking message on a thermostat is not a good sign. However, that’s not exactly the case with ‘cool on’.

Your Carrier thermostat will have a blinking ‘cool on’ message when the system goes into a delay mode – that is done to prevent the equipment from short-cycling. Under normal circumstances, the message will go away in 5 minutes, and the unit will start cooling your house.

What Does It Mean When Your Thermostat Says Cool On?

‘Cool on’ is your system’s special mode that is regulated by the thermostat. It is there to inform you that your AC has been turned on and is now cooling your house.

Why Is Cool On Flashing on My Carrier Thermostat?

If ‘cool on’ is flashing for only a few minutes, then you have nothing to worry about. It is a built-in safety measure that prevents short-cycling and protects the compressor from getting damaged.

Read: Carrier Furnace Error Codes – Troubleshooting Guide

Carrier Thermostat Blinking Cool On

In the majority of cases, ‘cool on’ is a delay message. You would simply have to wait for a few minutes and the unit will get back to normal operation. 

In about 5 minutes, the message should stop flashing. However, if it doesn’t, this might be an indication that there is something wrong with the system.

Thermostat Blinking Cool On, But No Air

Here are a few things that you can try to do:

  1. Set the thermostat to the lowest possible temperature – the mode should be ‘cool’ and the fan should be set to ‘auto’. Leave the unit for a while and check whether the system is going to start cooling or not.
  2. Check other thermostat settings – something might have made your thermostat switch back to setup mode. Also, do check the time on the device, as wrong settings can make the ‘cool on’ indicator start blinking.
  3. Replace the batteries or check the wiring, if your device is not battery-operated.
  4. If none of these steps made a difference, then you would have to check the actual cooling unit. Make sure that the system is getting power (you can also try turning the equipment on and off at the circuit breaker).
  5. Check your AC filter and replace it, if there is such a need. 
  6. Make sure that the AC coils are clean.
  7. At times, resetting the thermostat might resolve the issue. 

Read: Why Furnace Not Responding To Thermostat?

What Do I Do If My AC Isnt Blowing Cold Air?

If there is no air coming from the vents, then:

  • Check the thermostat settings
  • Replace the air filter
  • Make sure that the system is receiving electricity

If there is warm air coming from the vents, then:

  • Make sure that the fan is set to ‘auto’ (not ‘on’)
  • Replace the air filter
  • Clean the outside unit

Should the Thermostat Be on Auto or On for Cool?

Setting your fan to ‘on’ will help distribute the cool air around your house more evenly as the fan will continue to operate even when the air conditioner stops.

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However, that is pretty much the only benefit of leaving the fan on.

Switching the setting to ‘auto’ will make the fan work only when the cooling or heating is on. This is, of course, a more energy-efficient option.

Moreover, the ‘auto’ setting allows the moisture from the coils to drip and get drained outside during the warmer months. If the fan is running continuously, the moisture won’t get removed and will end up getting blown back into your house.

Finally, if you have ducts in the attic, they can get filled with warm air during the summer. In case the fan is always working, the hot air will get transferred into your house.

Read: Temperature Thermostat Problems

Should I Have My Thermostat on Heat or Cool?

If your house is too warm, then use the ‘cool’ setting. If it has become a bit chilly, then turn the system to ‘heat’.

By the way, your HVAC system can work even when both of these settings are off. You can choose to turn the fan to ‘on’ to circulate the air around the house more efficiently and to freshen up stale spaces, for example.

Read: Benefits Of A Programmable Thermostat

How Do You Turn Your Thermostat on Cool?

The ‘cool’ mode runs the air conditioner and lets you pick the maximum temperature. If the temperature rises above the setting, the thermostat will make the air con kick in.

‘Cool’ mode also helps dehumidify the house. 

Depending on the thermostat model, you would either have to pick the ‘cool’ mode on the device’s faceplate or use a cycle button to choose between ‘heat’, ‘cool’, and ‘off’

What Temperature Should I Set My AC to Cool?

78 F is the perfect balance between comfort and energy savings. Of course, you should experiment with the settings to find the perfect one for you.

By the way, if you want to save on your cooling costs, then you can try to rise the temperature when the building is unoccupied and during sleep. These ‘setups’ can result in up to 18% of energy savings.

Do You Turn the Thermostat Up or Down for Air?

If you want to make it hotter, then turn the thermostat up and vice versa.

In case, you simply want the unit to help you circulate the air around the house, you can switch the fan to ‘on’ without actually touching the thermostat temperature settings.

Read: HVAC Thermostat Problems

How Cool Should My House Be If It’s 90 Outside?

Air conditioners are designed to be able to cool your house to a temperature that is 20 degrees lower than the outdoor temperature. So, if it’s 90 F outside, you can easily get your house to 70 F.

However, keeping the indoor temperature at around 78 F or even 80 F would be a lot more energy-efficient. 

What Does It Mean When Your Furnace Light Is Blinking?

A blinking red light can mean that there is an issue with the pressure switch or inducer, furnace lockout, ignition failure, an open high limit switch, and so on.

Pay attention to the light sequence and consult the owner’s manual.

A flashing green light usually means that either the furnace is providing heat at the moment or that the furnace is on but there is no call for heat.

Why Is My Thermostat Blinking Heat On?

In the majority of thermostats, ‘heat on’ means practically the same thing as ‘cool on’. The HVAC unit will be ready to provide heat as soon as a 5-minute delay comes to an end.

This safety measure saves the equipment from getting damaged during short cycling. 

What Does Flashing Flame on Thermostat Mean?

The flame icon on a thermostat can start flashing if the compressor gets locked. This might happen after an interruption of some sort or power loss.

Usually, simply resetting the thermostat should solve the problem. 

Why Is My AC Not Coming On?

  1. A thermostat-related issue
  2. A low refrigerant level
  3. Clogged air filters
  4. A faulty capacitor
  5. A dirty condenser
  6. A tripped circuit breaker
  7. A damaged motor
  8. A clogged drain pan
  9. A faulty power cord

Why Is My Thermostat Not Turning the Heat On?

You might have to replace the thermostat’s battery. Also, make sure that the thermostat didn’t lose its settings – this could have happened during a power outage, for example.

Loose or damaged wires and no Wi-Fi connection might also be to blame.

What Does Wake Mean on Thermostat?

The thermostat sets a certain temperature during the ‘wake’ period – the time of the day when you are awake. By default, the ‘wake’ period is usually between 6 a.m. and 10 p.m.

Why AC and Fan Should Not Be Used Together?

It is a common misbelief that ceiling fans and air conditioners should not be used together.

Fans might send the warmer air closer to the floor, making everyone feel hotter; however, the appliances also create a refreshing breeze.In fact, using a ceiling fan together with an air con allows you to raise the thermostat setting by around 4 F and still feel comfortable.

Read: Why Does The Room Temperature Not Match The Thermostat Setting?