Outside Ac Wont Come On

Introduction

Having your outside AC unit fail to turn on can be incredibly frustrating, especially during hot weather. It’s a common issue that can arise from a variety of causes, leaving you without cool air when you need it most. Addressing this promptly is important not only for your comfort but also to prevent potential damage to your system’s components. This guide provides simple steps to troubleshoot the problem before calling a professional.

Common Causes of outside ac wont come on

Here are some of the most common reasons why your outside AC unit might not be turning on:

Tripped Circuit Breaker: An overload in the system can cause the breaker to trip, cutting power to the AC.
Thermostat Issues: If the thermostat isn’t set correctly or is malfunctioning, it won’t signal the AC to turn on.
Dirty Air Filter: A clogged air filter restricts airflow, causing the system to overheat and potentially shut down.
Power Switch Turned Off: It might sound simple, but sometimes the outdoor unit’s power switch gets accidentally turned off.
Condenser Fan Motor Problems: If the fan motor is faulty, the unit can overheat and shut down.
Frozen Evaporator Coil: Restricted airflow or low refrigerant can cause the evaporator coil to freeze, halting cooling.
Dirty Condenser Coils: Outdoor coils get dirty with leaves, pollen, and dust, reducing their ability to release heat.
Refrigerant Leaks: Low refrigerant levels can prevent the unit from starting.
Contactor Problems: The contactor is an electrical switch that starts the compressor and fan. If it fails, the unit won’t turn on.
Overload Protector Tripped: The overload protector shuts down the compressor if it gets too hot.

Symptoms Checklist

Check these symptoms to help pinpoint the problem:

The thermostat is set to “cool,” but no air is blowing.
The indoor fan is running, but the outdoor unit is completely silent.
You hear a humming sound from the outdoor unit, but the fan isn’t turning.
The circuit breaker for the AC keeps tripping.
Ice is visible on the copper lines or the outdoor unit itself.
The air coming from the vents is not cold.

How to Fix outside ac wont come on Step-by-Step Guide

Follow these steps to troubleshoot your AC:

Check the Thermostat: Ensure the thermostat is set to “cool” and the temperature is lower than the current room temperature. Replace the thermostat batteries if it uses them.
Inspect the Circuit Breaker: Locate the circuit breaker for your AC (usually labeled) in your electrical panel. If it’s tripped (in the “off” or middle position), flip it fully to the “off” position and then back to the “on” position.
Check the Outdoor Unit’s Power Switch: Look for a disconnect switch (a small box) near the outdoor unit. Make sure it’s in the “on” position.
Inspect the Air Filter: Remove and inspect the air filter in your indoor unit. If it’s dirty, replace it with a new one.
Clean the Condenser Coils: Use a garden hose (with a gentle spray nozzle) to clean the outside condenser coils. Remove any leaves, grass, or debris that are blocking airflow. Be gentle to avoid damaging the fins.
Check for Ice: Look for ice buildup on the copper lines or the outdoor unit. If you see ice, turn off the AC and let it thaw for several hours.
Inspect the Condenser Fan: Check if the fan blades are obstructed. Remove any debris carefully. Try to spin the fan blade with a stick. If it spins freely, it should be fine. If it is hard to spin, it indicates it might be motor issue.
Listen for Sounds: Listen closely to the outdoor unit when it’s supposed to be running. A humming sound without the fan turning might indicate a capacitor issue.
Reset the Unit (If Possible): Some AC units have a reset button. Check your owner’s manual to see if your unit has one and how to use it.
Check for Obstructions: Ensure there are no obstructions around the outdoor unit that could be restricting airflow.
Wait and Retry: After completing the above steps, turn the AC back on and wait for 15-30 minutes. Sometimes, the system needs time to reset.

Fix the Issue Without Buying Parts

Before resorting to replacing parts, try these free methods:

Resetting: Regularly reset the circuit breaker as a preventative measure.
Cleaning: Keep the air filter and condenser coils clean. This is essential for proper operation.
Inspection Tips: Visually inspect the unit regularly for any signs of damage, debris buildup, or ice.
Maintenance Basics: Schedule annual professional maintenance to ensure your AC is running efficiently and to catch potential problems early.

When Replacement Might Be Necessary

If the above steps don’t resolve the issue, some components might need replacing. This is typically a last resort after troubleshooting. Here are some common parts that fail:

Capacitor: A failed capacitor can prevent the fan motor or compressor from starting. (Estimated cost: $50 – $200)
Contactor: A faulty contactor won’t allow power to reach the compressor and fan. (Estimated cost: $50 – $150)
Fan Motor: If the fan motor is burned out, the fan won’t turn, leading to overheating. (Estimated cost: $100 – $400)
Compressor: Compressor failure is a major issue and often the most expensive to replace. (Estimated cost: $800 – $2000+)

Safety Warning

Always turn off the power to the AC unit at the circuit breaker before performing any maintenance or troubleshooting.
Avoid touching any electrical components with wet hands.
If you are uncomfortable working with electricity, contact a qualified HVAC technician.
Be careful when using a ladder to reach the outdoor unit.
Do not attempt to repair refrigerant leaks yourself; this requires specialized equipment and knowledge.

Tools You May Need

Screwdriver (Phillips and flathead)
Garden hose with a gentle spray nozzle
Air filter wrench (if required for your filter type)
Multimeter (for testing electrical components – if comfortable doing so)
Work gloves

FAQ

Here are some frequently asked questions:

Q: Why is my AC turning on and off repeatedly? A: This could be due to a dirty air filter, frozen evaporator coil, or a problem with the compressor.
Q: How often should I change my AC filter? A: Typically, every 1-3 months, depending on the type of filter and usage.
Q: What does it mean if my AC is blowing warm air? A: This could indicate a refrigerant leak, a faulty compressor, or a frozen evaporator coil.
Q: My circuit breaker keeps tripping. What should I do? A: Check for a short circuit or an overload. If the problem persists after resetting the breaker, call an electrician.

Conclusion

Troubleshooting your AC unit yourself can save you time and money. By following these steps, you can often identify and resolve common issues. However, if you’re uncomfortable with any of these steps or if the problem persists, don’t hesitate to call a qualified HVAC technician. Getting professional help ensures that your AC system is repaired safely and effectively.