Asked by: Olaf Beyschwang
home and garden indoor environmental quality

Why is my fan not turning on my AC unit?

Last Updated: 24th April, 2020

An air conditioner contactor is an electrical switch that controls the compressor and condenser fan motor. It is common for the contactor to go bad over time, which restricts the outside fan from working properly.

Click to see full answer.

Hereof, why is my AC condenser fan not working?

A slow condenser fan (or air handler unit fan) could be caused by a bad start-run capacitor. Unfortunately this condition could indicate a burned-out A/C or heat pump compressor motor. This can leave the fan motor running. A bad fan motor can also cause the fan to turn but only abnormally slowly.

Subsequently, question is, what happens if condenser fan doesn't work? When the condenser overheats, all of the components of the AC system will begin to overheat until they eventually get hot enough to burn and emit an odor. A failed fan will not only fail to produce cold air, but can even result in damage to the AC system due to overheating.

Besides, is the fan supposed to be on when the AC is on?

Keeping your fan on AUTO is the most energy-efficient option. The fan only runs when the system is on and not continuously. There is better dehumidification in your home during the summer months. When your fan is set to AUTO, moisture from cold cooling coils can drip and be drained outside.

Will AC fan run if capacitor is bad?

Symptoms Of a Bad HVAC Capacitor If you take a stick and spin the fan blade and the condenser fan starts to run, the run capacitor has likely failed. Even though the fan is operating, we recommend that the AC unit should be shut off. Without the run capacitor in the circuit, the motor will pull excess amperage.

Related Question Answers

Segismunda LuiƱa


How much does it cost to replace an AC fan motor?

When your air conditioner's fan motor breaks, it will typically cost about $300 to $600 to replace.

Fuad Berblering


How do I reset my AC?

Here are the steps you need to take to reset your AC thermostat.
  1. Shut Down Your AC at the Thermostat. The first step in resetting your AC thermostat is to turn it off at the AC unit.
  2. Find Your Circuit Breaker Box.
  3. Reset the Circuit Breaker for Your AC Unit.
  4. Wait 30 Seconds.
  5. Turn the AC Thermostat Back On.

Lorie Todoli


What causes AC fan motor to burn up?

Like any motor, an air conditioner fan motor can become overheated if it works too hard and doesn't receive proper maintenance. If your AC has worked for you most of the summer, the stress could cause the fan motors to burn out. Damaged wiring can cause a capacitor to fail, and the motor will not be able to start.

Jinfeng Poshevnev


Is it better to leave AC fan on or auto?

The fan only runs when the furnace tells it to. On cooling, the fan will run only when the air conditioner is running. Pros. The "auto" setting means less energy usage, because it keeps the fan running the least amount of time at the slowest speed needed for heating and cooling.

Lixiao Volck


Why is my AC outside unit fan not turning on?

Contactor problems.
An air conditioner contactor is an electrical switch that controls the compressor and condenser fan motor. It is common for the contactor to go bad over time, which restricts the outside fan from working properly. This is another part that must be repaired by a professional HVAC contractor.

Yanzhen Mihailets


How long do AC fan motors last?

How long does home AC compressor fan motor last? Air-conditioning compressor fan motor is designed to with stand up to 50 to 60 * c temp. You can run motor until it reaches to that condition. Standard well insulated motor will run continuously 24 hrs,then you may have to switch off to give rest to the machine.

Renata Rassl


Do all AC units have a reset button?

Find the Reset Button – Many air conditioning units will have a reset button on them. The button is usually red in color and fairly small in size. It should be marked clearly as a reset button. You can consult the instructions manual to determine if your air conditioning unit has that button, and find its location.

Zakia Alfaiate


How long can ac run continuously?

On a normal summer day, you can expect your air conditioner to run somewhere around 15 minutes during every cooling cycle. But if your cooling cycles are lasting 30 minutes, an hour or all day long, there's a good chance that something is amiss with your system.

Decorosa Genser


How do I know if my AC fan motor is bad?

Signs and Symptoms of a Bad AC Fan Motor
  1. The fan won't start even though the AC is on.
  2. The fan won't stop, even when you shut the AC off.
  3. The fan turns on, yet the blades are rotating very slowly.
  4. There's a rattling noise coming from the condenser unit when the fan is turned on.

Seckou Zerarra


Can you leave the AC fan on all night?

When you set your fan to “ON,” you're telling it to keep running 24 hours a day, 7 days a week, regardless of the heating or cooling setting. Keeping the fan on creates a more even distribution of heating and cooling, circulating the air if you have cold or hot spots in your house, like a bedroom above a garage.

Xianmin Jmelkov


When should cooling fan come on?

To check the temperature at which the fan comes on, turn the A/C off and keep the engine running until it reaches normal operating temperature. Most fans should come on when the coolant reaches about 200 to 230 degrees. If the fan does not come on, something in the control circuit is defective.

Flaviano Ban


How do I tighten my AC fan?

Tighten setscrew with screwdriver or Allen wrench. If air conditioner has round vent fan, tighten fan on motor shaft by inserting long-blade screwdriver through port in fan. Fan is installed in its housing with bolts, and vibration can loosen these fasteners. Then tighten them with wrench.

Fadia Calado


How does an AC fan work?

The fan for central air conditioning systems is connected to your furnace. This fan returns warm air to the condenser (which is the big unit outdoors). The air is re-circulated from the condenser back to the furnace, where it is turned into cool air and disbursed through ducts and vents into the rooms.

Sarka Xaus


Why is there no air coming from vents in my house?

The most common cause of low air flow through the vents in your home is blocked or dirty AC filters. Also known as vents, registers are the metal grates that let air flow from the AC ductwork into the rooms of your home. Vacuum these grates once a month, or anytime you see that dust has accumulated on them.

Cirina Filiu


How do you test an electric motor?

With an ohmmeter set to the Resistance or Ohms test setting, place test probes into the appropriate jacks, usually the "Common" and "Ohms" jacks. (Check the meter's operation manual if necessary) Choose the highest scale (R X 1000 or similar) and zero the meter by touching both probes against each other.