Why air conditioner fan not spinning fast enough

An air conditioner fan not spinning fast enough is definitely bad news, especially in the midst of hot summer days. Your AC plays a very important role in terms of the comfort level of your home and you want its fan to be fast enough to disperse cool air in all rooms. Even though some fan issues need a technician, there are problems that can be easily remedied through basic troubleshooting.

Your home’s air conditioning system has two fans, with the first one being in the air handler and the second one found in the condenser unit. These fans both have an equal part when it comes to keeping your home cool and comfy. Once you start noticing even the smallest change in the speed of your fan, there are several key areas that air conditioning technicians will inspect.

Why air conditioner fan not spinning fast enough

Check out the following common reasons why your air conditioner fan doesn’t spin fast enough. 

Air conditioner setting

There are air conditioner units featuring a fan button that lets the user choose a specific fan speed. Your AC unit might have been set to “Low.” If this is the case, it means that the fan will turn slowly and produce a minimal circulation of air that can create a problem once the room gets stifling hot.

Pressing the button labeled “Fan Speed” can boost the speed of the fan to a higher level and one more press will advance this even further. Air conditioner units may feature three fan speeds namely High, Medium, and Low. The maximum here is the high fan speed and it will command the internal fan to turn fast and produce a maximum circulation of air.

Presence of debris, dust, and dirt in the fan

Kids may insert debris like string or plastic bags into the intake grille or may get sucked up there. This debris can wrap around the fan and block its movement that can cause the fan to turn slowly. Aside from that,  if the fan is not installed properly in the AC unit, the fan blades may also end up hitting the sides of the housing of the fan that can result in a slowed-down fan rotation.

Side or front panels to the unit may be removed with the use of screwdrivers to show the fan compartment. Be sure to remove any debris present there. While the unit is still open, you can dampen a cleaning cloth and use it to wipe the blades of the fan. 

If you check the inner part of the housing of the fan, you might be able to notice the parts where the fan hit the housing. If the fan hits the housing, you need to remove the fan and install it again properly.  Regular checking of the fan during the maintenance of your air conditioner may be able to help prevent issues with debris.

Damage in the fan belt

There are air conditioners using a fan motor driven by a belt for pushing the cooled air all over your house. Normal use will lead to wear and tear signs on the belt that can leave this cracked or stretch. If this normal wear occurs, the fan may end up slowing down. There are also times when the fan may stop completely. There might be a need to have the belt replaced so that the fan will turn again.

Ice in the Unit

Even though a slow-turning fan may lead to a buildup of ice inside your AC unit, it is also possible for ice to build up because of a disconnected thermostat or weather conditions outdoors. Once ice forms inside the unit, this can end up preventing the air from blowing from vents and this can mirror the effects of a fan that turns slowly.

When the weather outside is lower compared to the setting in the thermostat while the unit has been set to cool, your unit might freeze. If the thermostat has been disconnected from the compressor or is broken, the compressor may continue running after the fan has been shut off which can leave the unit frozen. The central air must be defrosted if it freezes up.

Problems with the bearings

When the evaporator fan’s bearings are dirty or grimy, the fan won’t be able to freely turn as it should. After removing the air conditioner panels to show the compartment of the evaporator fan, try turning the fan by hand. You need to use electric motor oil for oiling the ball bearings if the fan is not turning freely. In case the fan is turning easily, it means that there is nothing wrong with the bearings and instead, there might be damage to the fan capacitor. You need to call a technician to handle the repairs if this is the case.

Run capacitor problems 

The run capacitor is another important part of your AC unit. If it starts to fail or is weak, the fan may end up slowing down. The compressor can still be heard running if it is the reason why the air conditioner fan has slowed down. You might want to shut off your air conditioning unit and call an expert to inspect it to prevent further damages to the system.

Tips to maintain the air conditioner fan

All parts of your air conditioner will experience wear and tear. However, there are a few things you can do to extend the lifespan of your unit’s fan.

For starters, it is important to put the fan in the right setting on the thermostat. Most fans have three settings namely auto, on, and off. The fans of your unit can also get dirty. You can inspect and clean them with regular bi-annual maintenance to ensure that they will run and function optimally.

If you suspect that there is a problem with your air conditioner fan, make sure that you schedule an appointment with a professional air conditioner technician who can check your system. The experts will help you ensure that you can enjoy your unit to the fullest.

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