Remove the fan blade from the motor shaft. Use a multimeter to test the continuity of the windings in the fan motor. The resistance should be low, less than 1 ohm, indicating that the windings are not open. A high resistance indicates an open winding and a faulty motor.
Some commonly occurring signs that you have a problem with your blower fan are that there is no air coming out of the registers even though the system is running, there is a loud rattling noise, and there is a burning-type smell within the system.
You will hear the capacitor clicking every few seconds if it is bad. This noise is the capacitor trying to release the energy needed for the unit's motors to start. If the start capacitor fails, you will typically hear the motor make a loud humming noise.
Your AC is rendered useless without a functioning fan or furnace blower motor. This could also mean that you need a furnace repair or should start looking at costs for blower motor replacement. In addition, you will either suffer from no air or weak airflow with fan problems.
What's the Cost of Repairing or Replacing a Fan Motor? The average cost of a condenser fan motor is between $300 and $500 (not including installation). If the compressor breaks, you are looking at a much costlier problem which could cost up to $2000. In some cases, your fan motor may be under warranty.
When your electric fan does not seem to work like it used to, the first thing you should do when troubleshooting is to make sure that the power supply to our power outlet works well. Turn your fan on to see if the motor works.
Disconnect the blower motor from its power source. Attach the multimeter probes to the motor terminals. A reading close to zero indicates good continuity, meaning the motor windings are intact. A reading of infinity suggests a break in the winding.
You can also troubleshoot a fan motor by testing the windings with an ohm meter. A 120V fan motor has black, blue, red, and yellow wires, plus a white wire, black wire, and two brown wires. Check the resistance between the white wire and each colored wire. If it reads zero, the motor winding may have a short.
Overheating. Overheating is one of the most frequent occurrences that can render the blower motor inoperative. If the motor has overheated, it may shut itself down to prevent damage. You should keep your HVAC clean and clear of any blockages or debris to avoid overheating and maintain efficiency.
The short answer: Definitely not. (Unless you have manually engaged your outside fan to run constantly, but it shouldn't be running for hours on it's own.) If your HVAC is functioning correctly, it should keep your house cool by cycling on for 15-20 minutes at a time—with distinct pauses in between each cycle.
Without the motion of the fans, the air will not be moved properly, and thus the until will not cool your home. The best way to keep your AC fan motor running properly is to ensure it gets regular maintenance and air conditioning repairs by a professional.
Motor Problems: The motor is the heart of the ceiling fan. Over time, it can wear out due to constant use, poor lubrication, or overheating.
Signs of Trouble: Watch out for wobbling blades, unusual noises, or sluggish fan speeds. These could indicate worn-out parts, loose connections, or a failing motor, all signs it might be time for a replacement.
A blower motor should last at least 10 years, and could last up to 20, depending on the type of HVAC unit you have in your home. There are a few warning signs that your blower motor is damaged, including little-to-no airflow coming from your vents, a burning smell, and skyrocketing energy bills.
Unusual and Loud Sounds
A failing blower motor may emit unusual sounds. This may sound like screeching or squealing if it has bad bearings. You may hear a rattle or a banging sound if something inside the motor has broken or come loose.
Some noises that a faulty engine will cause are backfiring, hissing, popping, and knocking. These sounds could mean problems inside the combustion flow. Engine knocking, for instance, happens when there are pockets of burning air-fuel mixtures that burn on their own instead of being caused by a spark plug.
Knocking, backfiring, hissing, spitting and popping are noises that can occur when there is an abnormality in the combustion flow. If you hear strange noises from the engine, schedule an engine service as soon as possible!