NYC Metro Area’s HVACR Blog

Commercial Air Conditioning, Preventive Maintenance Agreements, Residential HVAC

5 Signs Your Air Conditioner Fan Needs Replacing

air conditioner fan

If you are noticing signs that your air conditioning system might be having trouble, we understand why you’re trying to figure out what’s going on BEFORE it breaks down completely. Very smart of you!  When you can replace failing parts proactively before they cause bigger problems, you can often prevent a more expensive repair, not to mention inconvenient downtime (which will likely happen on the hottest day of the year). 

Your air conditioner fan (and there are actually at least two of them in most systems) is one part that can go bad and lead to a whole host of other problems.

Here’s a quick primer on air conditioner fans, and how the signs you’re seeing might point to  replacing one of these fans to prevent a breakdown. Plus, we’ll share how you can prevent this type of problem from happening to you again.

Which air conditioner fan is failing: blower and condenser?

In the most common types of central air conditioning systems, you have two types of fans:

Blower fan. The blower is part of the indoor air conditioning unit that removes the heat from your space and supplies cool air. The blower fan moves the cooled air through the ducts and registers and into the rooms or areas in your space. When the blower fan or motor isn’t working right, your system loses cooling power and can make strange noises.

Condenser fan. The condenser is the outdoor component of your air conditioning system. (This unit may also be located on the roof or in a mechanical room.) The condenser fan helps to cool your system’s refrigerant and expel excess heat outdoors. If this fan stops working, your system can overheat, leading to serious and expensive problems.

Keep reading to learn which air conditioner may be failing and what to do next.

5 signs of a bad air conditioner fan

Here are some common symptoms that you may be noticing, and the air conditioner fan problem that may be causing them.

1. Weak air flow

If the air flow coming from your vents is weak, this could mean that the blower is malfunctioning. Your air conditioner can experience problems when the motor that drives the blower slows down or burns out, or the fan itself slows down because it’s coated in dust and grime. If you have access to your indoor air conditioner unit, you can take a look at the fan and see if it’s turning very slowly or not turning at all.

Weak airflow can also be the result of clogged air filters or leaky ducts. Your best bet is to start with a professional inspection and cleaning of your system, which can take care of all the possible causes of poor airflow. 

Learn more: Top 10 Causes of HVAC Airflow Problems

2. Unusual noises

First of all, does the noise seem to be coming from the indoor unit or the outdoor unit?

Indoor noises. A buzzing noise inside could mean that the blower motor is working but the fan is not turning. If you hear a squealing sound, this could mean that the motor is not working correctly. Rattling or clanking usually means that a part has come loose inside the assembly.

Outdoor noises.  A rattling noise in the condensing unit can be caused by debris that has managed to get inside the unit and is being blown around by the fan.

Many of these problems can be fixed in a routine maintenance visit by an HVAC expert.

Learn more: Get to the Bottom of Air Conditioning Noise

3. Burning smell

Same question: is the smell coming from the indoor or outdoor unit?

Indoor burning smell. An electrical burning smell coming from the indoor AC unit could be a sign of the blower fan’s motor overheating. In this case, the system’s safety feature should automatically power down the unit. You may also see the blower fan slowing down or turning more slowly than usual.

Outdoor burning smell. An electrical burning smell can mean the condenser fan is malfunctioning and causing the compressor to overheat, which is very serious. A plastic burning smell can be caused by an object lodged into the unit, which can also cause it to overheat. In either case, shut down the unit immediately (if it hasn’t already shut down on its own) and get an HVAC professional to take a look.

4. Intermittent shutdowns

If your blower motor is aging and in need of replacement, your system may occasionally shut down on its own, especially on a hot day when the system is running for a long time. As the aging motor works hard to turn the blower fan, it may start to overheat and trigger the unit to shut down. 

In this case, you may need a technician to replace your blower motor and fan.

5. Fan stopped or moving slowly

As you investigate any of the other symptoms mentioned here, you may discover that either the blower fan or the condenser fan is turning slower than usual or not working at all. Oftentimes this problem can be caused by a bad capacitor, which is an electrical component that stores power and delivers it to the fan.  If this is the source of your air conditioner’s problem, you’re in luck: this is a quick and easy fix by your HVAC technician.

How to prevent air conditioner fan problems from causing a breakdown

Here’s the simple truth: all of the issues described here should be discovered during a routine preventative maintenance visit, even before you noticed the symptoms. Your HVAC technician would have replaced worn parts before they caused bigger issues, and cleaned system components to keep the units working properly.

Having an HVAC preventative maintenance contract not only prevents breakdowns, but also saves you money. 

Learn more about the types of contracts and the associated costs: ​​HVAC Service Contract Pricing Guide

If you’re in the NYC metro area, contact Arista for reliable maintenance from experts you can trust.