We're Always Open Call Us Today!

Air Conditioning Problems and Their Causes

hot outside weather

Minneapolis St Paul Air Conditioning Repair, Call Us Today For An Estimate

If you’ve ever spent a hot summer day without air conditioning, you know how uncomfortable it can be. Emergency air conditioning repairs can be expensive, so it’s important to keep your cooling system well-maintained. You should have your air conditioner serviced each year to ensure it’s performing properly. You should also be able to recognize common repair issues. Here are some of the most common air conditioning repair problems you may experience.

Lack of Cooling

On a warm day, the last thing you want is to turn on your air conditioner and find it’s blowing warm air. Here’s what could be causing your air conditioner not to cool your house.

Thermostat Settings

If your air conditioner is running but not cooling, check your thermostat settings first. When the thermostat is set to “On,” it will run the fan without necessarily cooling the air. Make certain that your thermostat is set to “Auto” instead of “On.”

Air Filter Needs Replacement

A dirty, clogged air filter will reduce airflow and make it harder for your A/C to reach your desired temperature. Your system will run longer to keep you cool, leading to higher energy bills. Dirty filters also affect your indoor air quality. Replace your air filters every one to three months to keep your HVAC system running smoothly.

Outdoor Unit is Dirty

Your HVAC cools your house by absorbing heat from inside through the evaporator, then transferring the heat to the outdoor unit (the condenser). If the condenser is dirty or blocked by debris, it cannot dispel enough heat. Keep the area around your outdoor unit clear. You can clean the outdoor unit with a garden hose on a gentle setting. Do not use a high setting on the garden hose or you could damage the air conditioner’s condenser fins.

Refrigerant Leak

Refrigerant flows through your HVAC’s outdoor and indoor coils, absorbing heat. When your air conditioner is low on refrigerant, it will not be able to absorb enough heat to keep your house cool. Signs of a refrigerant leak include:

  • Humid air indoors
  • Hissing or bubbling sounds coming from your outdoor unit
  • Ice buildup on the outdoor unit and the refrigerant line

If you notice any of these signs, turn your air conditioner off and call a repair expert right away. Running your air conditioner with low refrigerant can damage the compressor.

Air Conditioner is Frozen

Even in warm weather, an air conditioning unit can freeze. Some common causes of freezing include:

Poor Airflow

A lack of proper airflow is one of the most common causes of a frozen air conditioner. Without enough airflow, the air conditioner’s evaporator coil can reach below-freezing temperatures. When this happens, condensation can build up on the evaporator coil and become frozen.

Dirty Evaporator Coils

Dirt acts as a barrier between the refrigerant inside your HVAC unit and the air outside. This leads to the evaporator coils becoming too cold and freezing over. Keeping your evaporator coils clean will help to prevent your air conditioner from freezing.

Low Refrigerant

With an insufficient amount of refrigerant, your air conditioner will not be able to cool your home. Low coolant is a sign of a refrigerant leak. You should not lose any coolant if your air conditioner is working correctly. If you have a leak, it will need to be fixed by an HVAC technician.

What to Do if Your Air Conditioner is Frozen

Here are the steps you should take if your air conditioner freezes up.

  • Turn off your air conditioning unit. Don’t just use the thermostat to increase the temperature. Turn the air conditioner completely off. You can damage your cooling system if you continue running it when it’s frozen.
  • Replace your air filters.
  • Open the supply vents in your home.
  • Ensure that your air ducts and return vents are clear and aren’t blocked.

Left unaddressed, a frozen air conditioner can lead to more serious problems, including water damage. If your A/C is frozen, call an expert for air conditioning repairs as soon as possible.


When your air conditioner repeatedly turns on, runs for a few minutes, and then shuts down, it’s known as short-cycling. Short-cycling will lead to higher energy consumption and higher utility bills. It also creates premature wear and tear on your air conditioner. Possible reasons for short-cycling include:

Incorrect Size

If your HVAC system is not the correct size for your home, short-cycling may occur. An air conditioner that’s too big will cool your house quickly and then turn off. The constant switching on and off can cause some rooms to stay cool while other rooms are too warm. Over time, it will also place extra strain on your air conditioner, creating the risk of an early breakdown. If your A/C unit is short-cycling, an HVAC technician should examine it and make sure it’s the right size for your needs.

Thermostat Placement

Short-cycling is sometimes caused by a faulty thermostat. If your thermostat misreads your home’s temperature, it can shut the air conditioner off too quickly. The thermostat can misread the temperature if it’s in direct sunlight or near appliances that generate heat. A repair technician can move or replace the thermostat to resolve the problem.

Air Filters

If your air filters are clogged with dust and dirt, air will not be able to circulate properly through your house. The lack of proper airflow can cause your air conditioner to overheat and shut down. Again, you should replace your air filters every one to three months.

Frozen Evaporator Coils

As we discussed earlier, your evaporator coils can freeze if they become dirty, if there’s not enough airflow, or if your air conditioner’s coolant is low. Short-cycling is another symptom of an air conditioner that’s starting to freeze up. Scheduling regular HVAC maintenance will help you avoid this problem.

If you’re having trouble with your air conditioner, we’re here to help. Metro Heating & Cooling’s repair services cover any cooling problem you have. Contact us now for air conditioning repair in the Twin Cities area. We’re available to help you seven days a week.

Schedule a HVAC repair anywhere in the Minneapolis or St. Paul area today by calling (651) 294-7798 or by requesting an estimate online.


Contact Us

1220 Cope Avenue East, Maplewood, MN 55109