Ac wont turn on but fan does

Q: Help! It’s hot in my house, and the AC unit is running, but it isn’t blowing cool air. Why is my AC unit fan not spinning? Do I need to call a professional, or is this something I can fix myself?

A: If there are problems with the AC unit fan not spinning, the air conditioning unit will not keep a home cool. There are a few reasons why the fan would stop working even though the unit itself is running. Some of the solutions can be as easy as checking the circuit breaker or changing the filter, while others will require a professional to diagnose and fix the problem. In the meantime, check out some alternative ways to keep your house cool when your AC unit isn’t working.

The circuit breaker has been tripped because of overheating.

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If the AC unit fan is not spinning, the first thing to check is the circuit breaker. Take a look at the circuit breaker associated with the AC unit and see if it’s been tripped. A circuit breaker may trip from overheating due to outside temperatures and the motor’s heat. If this is the case, flip the switch at the electrical panel and see if that solves the problem. Some AC units may have a shutoff on the unit’s side; double-check that it hasn’t been switched off too.

The capacitor might be defective, and you might need to replace it.

A capacitor is a small cylindrical component that stores energy and powers the air conditioner’s fans. AC units have more than one capacitor, including the start capacitor, which starts the motor, and a run capacitor that keeps the motor running. If a capacitor is old and weak, it can cause the fans to stop spinning. If a capacitor is defective, it will need to be replaced by an HVAC professional. Delaying replacement could cause the motor to burn out and lead to more expensive repairs.

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The fan motor is burned out and needs to be replaced.

The fan motor is the workhorse of an AC unit. It can burn out when it’s overworked and not routinely maintained. Depending on the air conditioning unit’s age, an HVAC professional might suggest replacing the entire AC unit since fan motor replacement is costly.

The air filter might be clogged, and you need to clean or change it.

Another cause of an AC unit fan not spinning is a clogged air filter. If you can’t remember the last time you replaced the unit’s filter, it’s time for a replacement. This is an approachable solution for homeowners to tackle. Air filters can get clogged with dirt, dust, fur, pollen, and other debris. If the air filter is clogged or blocked, airflow will be restricted, which can cause ice buildup. If ice is around the evaporator coil, the fan could stop working and cause the coil to freeze. Sometimes replacing the air filter will solve the problem, but if the coil is frozen, it’s recommended to call a professional.

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A faulty belt might need to be replaced.

Over time, belts can become brittle and weak. It’s common in belt-powered AC units for the belts to be replaced when they cause a fan to stop spinning. An HVAC professional can easily replace old, worn, or loose belts.

It's a hot day and your air conditioner won't turn on! Before calling a repair service, there's a few things you should check. You may be able to save yourself some money and fix the problem yourself! "Use our quick navigation below to find the problem with your air conditioner"

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In this article we'll cover the six most common issues why your AC won't turn on. In many cases, you'll be able to resolve the problem yourself without calling a professional. However, keep in mind, if you're able to fix the issue, but the problem happens again, you should always contact a professional for service and repair. The root cause of the problem could be something serious, such as overheating or short circuiting. 

Do You Need an Air Conditioner Professional if Your AC Won't Turn On?

6 Most Common Problems Affecting Your AC Unit

Although, it's possible that the issue is serious and will require professional air conditioner repair. There's a good chance that the reason your AC unit won't turn on is because of one of these six common problems:

1. Power Issues
2. Thermostat
3. Air Conditioner Needs to be Reset
4. Shut-off Switch
5. Inside Power Switch
6. Clogged Condensate Drain Line

As stated above, it's critical that if the problem reoccurs to call a professional to do further troubleshooting. In addition, it's important to keep a regular HVAC maintenance schedule to avoid nasty surprises.  

What to Do When Your Home AC Unit Won't Turn On

If your AC unit won't turn on, here are the 6 most common reasons why and what to do.

If your AC unit won't turn on, the first thing you should check is if there was a blown fuse or a tripped breaker. There's a good chance that the problem is a tripped breaker if the circuit was overloaded.

This is especially common during the summer months when temperatures rise and your air conditioner unit is working hard to keep you cool. However, it is also possible that a power surge caused your air conditioner to blow a fuse or trip a breaker.

Check the Thermostat

Before calling an air conditioning professional for repair, check that your thermostat is set to cool. Here's how:

• Set the thermostat to COOL.
• Then set the thermostat's temperature setting at least 5 degrees BELOW the current inside temperature.

Check the Breakers

If your AC unit still does not work, you should check to see if the breaker was tripped. There are 2 places to check:

Electrical Panel - Check your main electrical panel to see if there's a circuit breaker "tripped" (older homes use a fuse box). If the circuit breaker has tripped, simply turn it off and then back on.

Disconnect Box - Sometimes an AC unit will have a shut-off box nearby. Within the shut-off box there are typically fuses.

If one of these fuses has "blown" the air conditioner won't operate. It's important that you Do NOT replace the fuse(s) unless the power is OFF. Do NOT attempt replacing the fuses unless you feel comfortable doing so. If you don't know what you are doing, even changing the fuses can be VERY dangerous. 

Caution

If your air conditioner keeps tripping the circuit breaker or blowing fuses, you may have a more serious problem. You should contact an air conditioner professional for repairs.

When your air conditioner unit won't turn on, the problem could be your thermostat. In order to keep your home cool, your AC unit relies on the thermostat to tell it when to turn on and shut down. If you suspect a problem, check the following:

• Check the screen on the thermostat. If it's blank, someone may have turned it off. Simply turn it back on and you should be fine.
• If you are unable to turn your thermostat on, check and replace the batteries.
• If after changing the batteries the screen is still blank, you may need to purchase a new thermostat. In most cases it's best to hire a professional to install it for you.

It may be that you simply need to reset your air conditioner. Not all AC units have a reset switch, so you may need to use the second method:

• If you're lucky enough to have a unit with a "reset" switch (located near the outside unit) all you need to do is simply press the switch.
• If you do not have a reset switch, you can turn OFF your air conditioner at the thermostat and wait for 5-minutes before turning it back ON.

If resetting your air conditioner solves the problem, you're good to go.

But if you find that your AC unit works for awhile and then you have the same issue again, you need to contact a professional for repair. You most likely have a more serious issue that needs to be addressed.

Many outdoor AC units have a shut-off switch. These switches are typically located near the unit and are inside a metal box mounted to the exterior of your home. They are sometimes labeled as an emergency shut-off.

If you recently had work done on your air conditioner, it's possible the workman forgot to flip the switch back to the ON position. The video below will show you how to check if your shut-off switch is the problem.

Watch the Video

The reason your AC isn't turning on may actually have nothing to do with the outside unit at all. The problem could be that the power to your furnace and indoor blower has been turned off.

In many cases there's a switch located near your furnace. It may be in plain sight or tucked away in a crawl space, closet, or attic. The switch can easily be mistaken as a light switch and someone may have accidentally turned it off. 

When the switch is in the OFF position, the blower is turned off. This can cause your inside unit to freeze and ultimately shut down your entire AC system.

We highly recommend labeling this switch to help prevent accidentally turning it off. 

The reason your air conditioner won't turn on could be because the condensate drain line is clogged. When AC units run, they create condensation, which is removed from the unit through a drain line.

When the drain line becomes clogged, a safety switch trips and shuts down your air conditioner. If this is your problem, you may be able to unclog the drain line with a shop vacuum. Sometimes the blockage can be removed from the drain line through suction. 

The suction from a shop vacuum could help remove a clog in the AC unit's drain line.

Another possible cause could be that your system uses a condensate drain pump to remove the water from your home (not all systems do). It's possible that the pump isn't working. When the pump stops working the safety switch will trip, shutting the unit down.

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