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Your Outside AC Unit is Not Running But Inside Is (Answered)

Your Outside AC Unit is Not Running But Inside Is

We've all been there, wondering why your outside AC unit is not running but the inside unit is. It's common and you're not alone. Many homeowners find themselves scratching their heads when their outside AC unit decides to take a break, yet the inside unit keeps humming along. This is a common issue with split-system air conditioners, which consist of an outdoor unit housing the compressor and condenser, and an indoor unit responsible for blowing air through your home's ducts. While you may feel cool air coming through your vents, a non-operational outside unit can actually be a sign of an underlying problem.

It's an issue that not only affects your comfort but could also signal a more severe problem looming on the horizon. Addressing this inconsistency promptly is crucial to prevent higher energy bills, further damage to your AC system, or even a complete breakdown. So, let's get to the bottom of why this happens and what you can do to fix it.

Inside AC Unit Running and Outside AC Unit Not Running (Quick fixes:)

If your outside AC unit is not running but the inside AC unit is, you can try to solve the issue quickly first by:

  • On-Off: When your outside AC unit is not running, sometimes it's as simple an on/off switch being accidentally turned off. Most outside fan units have an on-off switch in a small box by the unit.
  • Circuit breaker tripped: A circuit breaker could have been the cause of your outside AC unit to stop working properly. Find the circuit box to see if the breaker hasn't tripped. If you find that it has, flip it all the way off and then back on. If the breaker keeps tripping which stops the outside unit from working, then you should consult a verified electrician to look into the issue.
  • Thermostats has wrong settings: Check your thermostat and make sure it is set to "cool" and that is set to a lesser temperature than what you think is room temperature. If this turns out to be the problem and your inside unit is running, then your inside unit might be the culprit.

If those didn't fix the outside unit from not working, then let's move on to larger issues.

Thermostat Troubles

Ever found yourself scratching your head, wondering why the outside AC unit isn't running, while the inside one is? A very common culprit behind this issue could be your thermostat settings. In this section, we'll delve into how incorrect thermostat settings could be affecting your outside AC unit and guide you through the steps to reset and rectify the situation.

How Incorrect Settings Can Affect the Outside AC Unit

Your thermostat acts as the brain of your HVAC system, communicating between the indoor and outdoor units. Incorrect settings on the thermostat can disrupt this communication, leaving your outdoor unit non-operational. This can happen if the system is set to "fan only," causing only the inside fan to circulate air without engaging the outside unit to cool the air. Other thermostat settings that can lead to similar problems include incorrect time or day settings, or an unresponsive touch screen.

Steps to Check and Reset the Thermostat

Before calling an HVAC technician, there are simple steps you can take to reset your thermostat. Firstly, ensure that it's set to "cool" and not just "fan." Check the temperature settings and make sure they are set below the current indoor temperature. Additionally, verify that the time and day settings are correct. Most modern thermostats have a reset button, or a series of commands you can follow to restore factory settings. If none of these steps work, it may be time to call in the professionals.

Troubleshooting the thermostat is a logical first step to resolve the issue of an outside AC unit that's not running. Incorrect settings can often be the culprit, and thankfully, they are easy to rectify. So before you jump to conclusions or dial your HVAC technician, a simple thermostat check could save you time and money.

Mechanical Issues

If you've ruled out thermostat troubles and still find your outdoor AC unit non-operational, it may be time to consider mechanical issues. These are problems that require a more in-depth investigation and usually the expertise of a professional. In this section, we will focus specifically on two common mechanical failures: the capacitor and the contactor. Understanding the signs that these components might be faulty can save you valuable time and possibly prevent further damage.

Capacitor and Contactor Failure

The capacitor and contactor are crucial components of your outdoor AC unit, responsible for storing energy and regulating the electrical flow, respectively. When these parts fail, the outdoor unit won't function properly. A failed capacitor often exhibits a swelling or leaking appearance. The contactor, on the other hand, can have visible signs of wear, pitting, or even melting. Both of these issues usually necessitate replacement rather than repair.

Signs That These Might Be the Issue

If your outdoor unit makes a humming noise without fully starting, or if it intermittently starts and stops, these are potential signs that the capacitor or contactor might be failing. Furthermore, if the circuit breaker trips frequently, it could also be indicative of a mechanical issue. These are problems that should be dealt with immediately to prevent further damage and ensure the longevity of your AC system.

Understanding the role and function of the capacitor and contactor in your AC system is crucial when troubleshooting mechanical issues. These components are often the unseen heroes of your cooling system, and when they fail, the consequences can be immediate and disruptive. If you suspect that these could be the issue, it's best to call in the experts for a more thorough diagnosis and solution.

Refrigerant Levels

As we delve deeper into potential reasons why your outside AC unit may not be running while the inside is, it's important to consider the level of refrigerant in your system. This chemical compound is vital for the cooling process, and if levels are too low, you may encounter issues with your outdoor unit. In this section, we'll look into how low refrigerant levels can adversely affect your system and why professional help is often needed to resolve this issue.

Explain How Low Refrigerant Can Cause the Unit to Stop

Low levels of refrigerant can lead to an array of problems, most notably the inability of your outdoor unit to function effectively. The unit may not run because there's not enough refrigerant to complete the cooling cycle, causing the system to shut down as a safety measure. In some cases, you might hear unusual sounds like hissing, which can be a sign of refrigerant leaks.

Why This Requires Professional Help

Addressing refrigerant levels is not a DIY task for most homeowners. Properly diagnosing a refrigerant issue and handling the compound requires specialized tools and knowledge, as improper handling can be dangerous. Licensed professionals have the expertise to safely evaluate your system, locate any leaks, and replenish the refrigerant to the required level, ensuring that your system operates efficiently.

If you suspect that low refrigerant levels could be the cause of your outside AC unit's issues, it's crucial to act quickly by getting professional assistance. Allowing this issue to linger can lead to more severe problems like compressor failure, which can be much more costly to repair. It's a technical issue that necessitates expertise, both for your safety and the longevity of your air conditioning system.

Inside AC unit is working but outside AC unit is not working

Lack of Power to the Outside Unit

If you find that the inside part of your AC is buzzing along but the outside unit isn't cooperating, there's a chance that the issue could be as simple as a lack of power. Power issues are not uncommon, and they can occur for various reasons, including a flipped disconnect switch or potential wiring problems. In this section, we'll explore these possibilities and provide guidance on how to address them.

Check the Disconnect Switch

Believe it or not, sometimes the issue is as straightforward as a switched-off disconnect switch. Located near the outside unit, this switch is designed as a safety feature and is often turned off for maintenance or during the off-season. Make sure the switch is in the 'on' position, and see if this resolves the issue.

Potential Wiring Problems

If the disconnect switch is in the correct position, but your outdoor unit still won't run, the next place to look is the wiring. Damaged or frayed wires can lead to a loss of power. Since electrical work can be dangerous, it's advisable to call a qualified technician for this kind of issue. They can properly assess the wiring, make necessary repairs, and ensure everything is up to code.

If you've eliminated other possibilities and your outside AC unit still isn't running, then it's time to consider power issues seriously. Checking the disconnect switch and inspecting the wiring are solid first steps in identifying what might be wrong. For electrical issues, it's best to consult a qualified professional to ensure your system is both effective and safe.

When to Call a Professional

If you've been grappling with an outside AC unit that refuses to work while the inside unit hums away, you may be wondering if it's time to call in the experts. Knowing when to seek professional help can save you both time and money, and can also prevent potential hazards that come with DIY fixes. In this section, we will discuss the scenarios that definitely require the expertise of a qualified technician and emphasize why attempting to resolve certain issues yourself could be risky.

Outline Scenarios Where Professional Help is Needed

Certain situations simply demand a professional touch. For instance, if you suspect refrigerant leaks or electrical issues, it's not just advisable but essential to call in an expert. Diagnosing and repairing these issues usually require specialized tools and knowledge that the average homeowner doesn't possess. Additionally, if you've tried basic troubleshooting steps like resetting the thermostat or checking the disconnect switch with no success, a technician's input becomes invaluable.

Emphasize the Risks of DIY Troubleshooting for Certain Problems

While some problems can be fixed with a little DIY spirit, there are instances where attempting to solve an issue yourself could lead to further complications or even safety hazards. Electrical work, for instance, carries the risk of shock if not handled correctly. Similarly, incorrectly dealing with refrigerant can pose health risks and may even be illegal without proper certification. When it comes to these complicated or hazardous issues, the risk far outweighs any money you might save by not hiring a professional.

Tackling complex AC issues without adequate training or tools is not only a gamble but a risky one at that. Don't let the temptation of a DIY fix lead you down a rabbit hole of potential problems. The scenarios discussed here underscore the importance of knowing when to step back and let a qualified technician take the reins. Remember, it's not just about solving the issue but ensuring that it's done safely and effectively.

outside ac unit is not working but inside ac unit is

Wrapping It Up

If you've ever found yourself sweating it out because your outside AC unit won't cooperate, even while the inside unit is working, you're not alone. Throughout this article, we've explored various reasons for this enigmatic behavior, from thermostat troubles and mechanical issues to low refrigerant levels and power challenges. We've also emphasized the scenarios in which you should definitely consider calling a professional technician for help.

Faced with an AC unit that's not fully functional, time is of the essence. It's not just about comfort, but also about preventing a small issue from morphing into a much larger, and potentially more expensive, problem. You have the information you need; now it's time to take action. Whether that means rolling up your sleeves for some DIY troubleshooting or making that call to a qualified technician, don't delay. Your comfort—and possibly your wallet—depends on it.

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