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Why is My Outdoor AC Unit Not Starting?

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Some homeowners in Sacramento may panic and call an HVAC technician for help as soon as they realize that the external unit hasn’t come on after they turn the AC on. Some homeowners are great at DIY when it comes to repairing appliances. You can save some money by trying some basic solutions before asking a professional heating and air company for help. Today we share some insider trade secrets with you.

Check the Thermostat Settings

The outdoor unit of your air conditioner may fail to turn on when adjusting your thermostat. Adjust the temperature setting to a level which is lower than the current ambient temperature. If it is working correctly the outdoor unit will start humming a few minutes after you input those new thermostat settings. One of the most common culprits, when the thermostat is not connecting to the outdoor unit is the batteries. Believe it or not, we get calls often and the problem is a corroded battery in the thermostat.

Check the Circuit Breakers

It is also important for you to open the electric panel in order to check whether the breaker of the external AC unit has tripped. That breaker is usually labelled as “AC”. Flip it to the “off” position and wait a few minutes before moving it to the “on” position.

Call a Sacramento heating and air company to inspect the AC in case the outdoor unit starts and stalls shortly after you have reset the circuit breaker. This precaution is necessary because the system may have a serious underlying problem that is causing the breaker to keep tripping.

Check the Power Switch

The power switch of the air conditioning unit usually looks like any other switch within the home. This power switch may be located in the attic, crawl space or closet close to the furnace of the unit. Locate this switch and turn it back on in case it had been turned off inadvertently.

Clean the Outdoor Unit

You should also consider cleaning the outdoor unit in case your AC fails to start. Cleaning the unit can remove the debris which may be causing it to overheat each time it runs for a while. Getting rid of all the debris around it will therefore allow air circulation to be restored around that unit so that it stays cool and doesn’t trigger the shutdown switch.

Reset the Outdoor Unit

The outdoor unit may also be failing to start simply because its safety switch was triggered and it turned off the unit. Electrical overloads and overheating are some of the reasons why the safety switch may be engaged to protect the unit from damage.

Start by turning the power switch off from the thermostat inside the home. Wait for a few minutes (five minutes, for example) and turn that switch back on. This will reset the safety switch and the unit will power up once more.

Check the Condensate Pump

The external unit of the air conditioner in your Sacramento home may fail to start in case someone accidentally disconnected the condensate pump. That pump helps to force out any water that is collected as the AC system does its work.

Water can therefore accumulate within the AC unit in case this pump is disconnected. The outdoor unit fails to start as a way to avert any serious damage which can result once the condensate pump isn’t working to get rid of the water which collects as warm air cools and allows water droplets to form. Reconnect this pump and the exterior unit will start working.
You should make sure that the power is turned off before you attempt to perform any repairs or maintenance work on your AC unit. This will safeguard you from any electrical hazards that you may be exposed to while you work. We recently published a blog about causes of wet AC filters which gives you a more in-depth look at the condensate pump.

Enlist the help of a Sacramento HVAC professional in case you are unsure about what you should do to get the external unit to start working again.

Fox Family Heating & Air serves Sacramento, Rancho Cordova, and all of Northern California. If you’re looking to schedule HVAC service in these areas, give us a call!

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