The words "preparing your air conditioner for the summer" in front of a person working on an air conditioner.

The arrival of summer in the Dallas Fort Worth area means a lot of things: parties with friends, vacations, and fun in the sun. It also means your air conditioner system will be seeing a lot of use in the Texas heat. At Cote’s Mechanical, we’ve put together a list of things you can do to help get your air conditioner ready for the summer months.

It is important to remember that air conditioning is not just a matter of comfort; it is also important for keeping you safe in the intense summer heat.

Caution: Given the dangers of working with electricity, it is best to leave air conditioner maintenance to professionals.


Before doing anything with your air conditioner unit, be sure to shut off the condenser’s power at the service panel. Generally, the condenser will also have a 240-volt weatherproof disconnect box located close to the air conditioner unit. You also need to turn off the disconnect box as well.

Condenser Coils

Condenser coils are a vital part of your air conditioning system. The condenser coils are responsible for transferring the heat inside your home to the outside of it.

Over time dirt and debris can accumulate on condenser coils. They will need to be cleaned to ensure that they function as they should.

Condenser Coil Cleaning

CAUTION: Before cleaning your condenser coils, it is vital that you shut off the power to it.

To clean the condenser coils, use a garden hose to spray off dirt, grass, and other obstructions on your condenser coils. Do NOT use a vacuum or brushes to clean coils, as this can cause damage.

Air Conditioner Condensate Drain Line and Drain Pan

A tech discusses options with a Justin Homeowner

When air and excess humidity gets removed from the air conditioner, it is “caught” by the condensation drain pan.

The drain line allows condensation to drain from out of the system.

If your drain line becomes clogged, it can lead to bad indoor air quality caused by the growth of mold and mildew, and increased humidity. A clogged drain line can also result in water damage and even cause your air conditioner to stop working!

Signs that you Have a Clogged Drain Line

Determining if your drain line is clogged can be difficult. Below we’ve included possible signs that it is clogged. Please note this list is not conclusive.

  • The drain pan is full. The drain pan is the first place to look for signs of a clogged drain line. You can inspect it by looking underneath the unit or, if you have a window air conditioner, by opening up the drain valve. Dripping sounds can be a sign of standing water in the pan. If you notice the drain pan consistently filling up, it indicates that the water has nowhere else to go. You can use a wet/dry vacuum to get water out of the pan so it doesn’t overflow until you can get the line cleared or get a professional out to work on it.
  • Your air conditioner has condensation on it. While water dripping from the back of an air conditioner is normal, water puddling inside your home is a sign of trouble. Condensation appearing on an air conditioner is a common indicator that the drain line is clogged. If lines are clogged, it can result in excessive condensation, causing water to accumulate in the drain pan, which can lead to possible water damage. 
  • Your evaporator coil is frozen. An air conditioner’s evaporator coil is located above the condensation pan (typically located on the floor) and drain line. The evaporator coil cools down warm air, which results in the formation of condensation in the air conditioner unit. If the line clogs or the air conditioner stops blowing warm air over the coil, the condensation on the coil will freeze up. That causes the entire evaporator to freeze. When a coil freezes up, an air conditioner will often run constantly, although there won’t be any cool air coming from the vents—driving up the cost of your utility bill!
  • Mold or mildew appears. If you have standing water in a drain line or drain pan, it can result in the formation of mold and mildew. You might be able to detect the smell of mold or mildew when you first turn on your air conditioner. Be sure to also look for signs of mold or mildew by your central air conditioning system. Condensation or a slowly overflowing drain pan can lead to mold and mildew forming around and in your air conditioner.
  • Your air conditioner isn’t working. A clogged drain line is one of the most common reasons an air conditioner stops working. This can be caused by an air conditioner’s safety shut-off feature being activated if water drips from the system or if the condensation pan gets filled up too high.

Clearing AC Drain Line

Step One: Shut Off the Air Conditioner 

It is vital that you shut off your air conditioning system’s panel at both the thermostat and the breaker box.

Step Two: Locate Your Condensation Drain Line

The drain line will be located on the outside of your house and is most likely close to the outdoor unit. Look for a white, grey, or black inch-long PVC pipe attached to the outside wall of your home. Once you’ve found it, you need to follow it to the drain pan.

Before going on to the next step, get rid of any water in the drain pan by using dry rags. If the pan has bacteria or mold in it, use additional rags, soap, and water to clean it. Please take care, as some molds and bacteria can be toxic.

Step Three: Find the Access Point

The drain line’s access point is located along the line and close to your home’s inside drain pan. The majority of drain lines will have T-shaped pipes known as vent tees that have a cover or cap on them.

Take off the cap. Put on protective gloves and check the inside for any signs of major blockage.

If you come across large pieces of debris, remove them with your glove-covered hand or break them up by using a wire brush.

Step Four: Use Distilled Vinegar to Flush the Drain Line

Distilled vinegar is a strong acid that kills mold and bacteria while also breaking down debris and sludge.

You must wear eye protection, a facemask, and the gloves you were wearing from the last step.

Next, take off the drain line cap and pour about ¼ a cup of distilled vinegar into it.

Allow the vinegar to sit for at least 30 minutes. The longer it sits, the cleaner the line will be.

If you notice bad smells or the line hasn’t been cleaned in a long time, allow the vinegar to sit for a few hours before you do the next step.

Step Five: Flush the Drain Line Using Water

Once the vinegar has done its job, use water to flush the drain line as you did with the vinegar. Be sure to check the water from your drain pan.

The flushing process doesn’t have to last a long time; it just has to last long enough to clear out the line. When there is no more debris coming from the line and the water is coming out of the outdoor drain at a consistent pace, it is good to go.

Step Six: Repeat the Process If Needed

If the water still isn’t draining right, this could be a sign the line is still clogged up. If that is the case, you’ll need to repeat the process. When you do it again, have the vinegar sit for a longer period.

AC Filter

A filter is a crucial component in your air conditioning system. Over time it can get dirty, leading to your air conditioner not operating as efficiently.

AC Filter Changing or Cleaning

It is a good idea to clean or replace your air conditioner filter at least once every six months, if not more. If your filter appears to be clogged up by dust, it’s a sign you’ll need to clean or replace it.

There are a number of factors that impact the longevity of your air conditioner filter. Some of these include:

  • The air conditioner’s age
  • Air quality
  • If you have pets
  • The season
  • If you have particular medical conditions, such as certain respiratory conditions, you’ll want to make sure any filter maintenance is more frequent.
  • If you have allergies, you’ll want to make sure your filter is changed or cleaned more regularly.

AC Coolant Lines

Coolant lines connect the condenser unit to the inside evaporator coil. Without them, your air conditioning unit wouldn’t be able to function.

Inspect Your Coolant Lines

Damage to your coolant lines or their insulation can result in your air conditioner unit losing cooling power. If you have a coolant line leak, it can not only increase your energy bill but also damage your air conditioner unit. It is important to inspect your coolant lines regularly. 

Be sure to also look for damaged or missing insulation. If you have missing or damaged coolant line insulation, replace the old insulation sleeves with new ones, or use foam installation tape to wrap the lines in a spiral manner.

Testing the Air Conditioning Unit

To make sure that everything is working correctly, you’ll want to test out your air conditioning unit.

First, the unit must be allowed to dry out completely.

Then, turn on the power to your condenser unit by doing the following.

  • Set your home’s thermostat to “off.”
  • Switch on the power for both the main panel and the disconnect box.
  • Turn your thermostat to “cold.”

If cold air comes out of your vents, that’s a good sign!

Air Conditioning Services in Dallas-Fort Worth

A technician leaves a home.

When it comes to something as important and complex as your air conditioning system, it is important to utilize the services of a professional. If you’re in North Texas or the surrounding area, the team at Cote’s Mechanical can help you get your air conditioning unit ready for summer. We provide a wide range of HVAC services to both residential and commercial clients. We also offer 24/7 emergency HVAC services and inspections. 

Cote’s Mechanical proudly maintains an A+ rating from the Better Business Bureau. 

When you need help getting your air conditioning system ready for summer and beyond, contact us for fast service!