In this article, we will discuss some of the things that can cause outdoor ac unit not working and highlight possible methods of resolving them.
You’ve been using your air conditioner for a while now but recently, you’ve noticed something different about it. You turn it on again for another run and you hear the normal sound of the AC coming on.
However, your house isn’t cooling as it usually does. A brief investigation leads you to discover that the outdoor AC unit is not working but the indoor unit is.
Generally, this could mean one of two scenarios; the outdoor AC hums but the fan fails to spin or the entire outdoor AC unit is unresponsive.
Reasons Why the Outdoor AC Unit Fan May Not Be Spinning
If your AC outdoor unit fan isn’t running, here are some typical causes:
- Capacitor issues
- Problems with the contactor
- Limited power supply
- Fan motor burnt out
Capacitor issues
One major cause of the outdoor AC fan not working is when it develops capacitor issues. The capacitor is the component that stores up the energy that powers the AC’s fans.
However, just like batteries, some capacitors tend to lose their energy-storing attributes over time. This is usually a result of power surges and high temperatures.
You can test if your AC’s capacitor is the issue by sliding a long, thin (but strong) wooden or plastic rod (not metal to prevent electric shock) through the grate of the outdoor AC’s fan while the appliance is one.
Use the rod to give one of the blades a slight push to get it spinning and if it works, then the capacitor is faulty.
A faulty capacitor can only be replaced by a professional. Although you can still continue using your AC with the capacitor bad.
However, it will only compound the problems as not only will your fan motor work harder, it will ultimately, burn out over time leaving you with more money to spend on replacements.
In addition, if the capacitor is shared by the AC compressor (as is common with dual capacitors), your unit could experience even more damage as the compressor may overheat.
If after poking the AC unit’s grates to spin the fan with the rod, it refuses to start, then there’s likely a build-up of debris around the fan axle, the motor bearings are dirty or jammed, or the fan motor itself is faulty.
Problems with the contactor
The contactor in an AC outdoor unit controls the fan motor. Thus, if it develops a problem, the outdoor AC fan will not spin.
This is not something you’ll be able to do on your own without technical experience in the field. So, you will need to bring in a professional to have a look at it.
Limited power supply
If for some reason, the power supply to the fan assembly is insufficient or limited, the outdoor fan will not spin. So, be sure to check that the electrical current is sufficient enough to power it.
If there’s nothing wrong with the power supply, then it may be an internal issue blocking power from reaching the fan. This will require a professional to resolve it.
Fan motor burnt out
AC fan motor burning out usually occurs when the unit has undergone too much stress. Also, the fan motor can burn out from wear and tear usually in cases where the AC unit is poorly maintained.
You’ll be able to detect these issues early if you perform regular inspections on the AC unit. Failure to do this can lead to more damage and ultimately cost more in repairs.
The Entire Outdoor AC Unit Is Unresponsive
In some cases, the entire outdoor unit may be unresponsive. Thus, there’d be no air emitting from the AC vents.
In cases like this, your best bet would be to call an HVAC professional. However, there are a couple of troubleshooting tips you can try first.
- Clean the outdoor AC unit
- Take a look at the thermostat
- Outdoor AC unit is locked
- Check that the AC emergency/shut-off switch is on
- Outdoor AC unit tripping breaker
- Check the indoor AC unit’s switch
Clean the outdoor AC unit
Sometimes, dirt and a build-up of debris in the unit can cause the compressor to overheat. When it overheats, some AC units shut down.
First, turn off and disconnect the AC unit from the power source. Then do a thorough cleaning of the outdoor unit to rid it of dirt.
Take a look at the thermostat
You shouldn’t overlook the fact that either you (or someone else at home) unconsciously set the thermostat too warm.
So, be sure to check that your thermostat is powered on and set to cool or to a temperature that is at least 3 degrees lower than your current ambient temperature.
Outdoor AC unit is locked
Some air conditioner units come with a safety lock that gets triggered to protect the unit. If this is the case, something as simple as a reset should get it working again.
You can reset the unit by switching the system off at the thermostat or breaker. Next, wait for about one minute and switch it back on.
In 10 minutes, the outdoor unit should commence operations again. However, if it fails to start up, then the problem is likely more troublesome than you can handle and will need professional assistance.
Check that the AC emergency/shut-off switch is on
If there is a metal box hanging on the wall not far from your outdoor unit, take a look at it. Inside that box is an emergency or shut-off switch.
Be sure the switch is in the “on” position as it might have been inadvertently left in the “off” position by someone.
Outdoor AC unit tripping breaker
In some cases, the outdoor AC unit may affect your home’s circuit breaker by tripping it off when the AC is turned on.
Circuit breakers tend to get overloaded and, as such, trip off when it happens. This is often common whenever there’s a power surge.
If the breaker in your home has been tripped off after turning on the AC, try to flip it back on. If it trips off again, then you likely have an electrical problem.
Do not try to flip it back on as this could cause some damage to your AC unit as well as other appliances. Just try to get a professional electrician to help resolve the issue.
Check the indoor AC unit’s switch
Some indoor units come with a switch that controls the outdoor unit. This switch can be located in the closet, attic, or any other rarely used space in the home.
If the switch is off, the AC unit may freeze. When this happens, the entire air conditioning system is shut down.
Final Words
In truth, having to deal with AC issues can be tedious especially if you’re the only one struggling to get it working again.
You can discover a few troubleshooting tips on your own in this article that can help you restore your air conditioning unit to normal.
However, if you still can’t get it to operate as it should, you will need to bring in a professional to assist you or get a new AC unit altogether if the current one is old enough to be replaced.
