How To Clean Your Condensate Drain

by | Aug 2, 2017 | HVAC Blog

Monsoon Moisture Madness!

Monsoon season is the wettest most humid time of the year in southern Arizona. It’s when you intuitively know in order to feel cool it helps to turn the thermostat down a degree or two from where you usually feel comfortable. This action works because your air conditioner does more than just cool. It also regulates the amount of humidity in your home– more cooling creates dryer air– and a less sticky you! When it’s steamy your AC works overtime to remove water vapor from the air but where does it go?

What Is A Condensate Drain?

Moisture in the air condenses on the evaporator coil then drains by gravity or is pumped out of the air conditioner through a small PVC pipe called the condensate drain. A little clog in your condensate drain can create a huge problem!

Clogged Condensate Line

How Does The Condensate Drain Get Clogged?

If the coils are dirty, (and without maintenance they will eventually get filthy,) the condensate will carry dirt and debris into the condensate drain which could become caked or even clogged. Algae growth increases during the warm moist monsoon season which also contributes to drain blockage.

Why Is A Clogged Drain A Problem?

When the line is completely blocked you could see distressing signs of water leaks in your home which may be difficult to distinguish from a plumbing or roof leak, especially in monsoon season. When your condensate pan overflows it can cause corrosion of metal parts of your mechanical equipment and hundreds of dollars-worth of damage to drywall, carpentry and flooring. A poorly draining condensate line can decrease the effectiveness of your highly efficient HVAC equipment and cause musty odors from algae and mold.

How Do You Know If The Condensate Drain Is Clogged?

No cooling could be the first sign of a backed-up condensate line because some units have an overflow safety switch which shuts the power off before the pan overflows and ruins your home. Your service tech can tell you if you have this handy safety feature on your unit and can install one pronto if it doesn’t.

Condensate Safety ValveThe condensate line should drain to the outdoors and during humid weather you should see plenty of water dripping from it. If it’s not dripping, it’s not draining! Dripping anywhere else is a problem. Look for water coming from the bottom of the cabinet or exhaust fans. If there is standing water in the drain pan, your condensate drain is clogged! Act quickly if you notice any water spots or damage to the ceilings, carpet or furnishings near the AC. When an air conditioning system is mounted above a furnace you might see rust forming on the furnace. Always remember water and electricity Do Not Mix! Call your professional at Oasis when in doubt.

How To Clean Out Your Condensate Drain

  1. Turn off the power to your HVAC system at the breaker and the thermostat.
  2. Find the condensate pan. It may be located directly under the indoor air handler in your attic or utility closet. It may be covered by a removable access panel.
  3. If there is standing water in the condensate pan, your drain line is probably clogged. Use a rag or wet/dry shop vacuum to remove the water.
  4. Clean the pan with soap and water.
  5. Find the condensate drain outlet which might be located outside your house near the foundation. Many times the clogged drain can be cleared with wet/dry vacuum suction. You can also try removing the clog with a plumber’s snake.
  6. Try to identify the access point on the drain line which might be a T-shaped vent with a PVC cover. Remove the cover and inspect the drain for debris. /
  7. Use the access port to flush the drain with white vinegar, diluted hydrogen peroxide, or hot water and a drop of dish soap. Do not use bleach because it kills plants, and damages plastics and siding. Allow the solution to soften remaining debris for about 30 minutes. Flush the drain again with water and verify the water is draining freely.


If you’re unable to clear your air conditioner’s drain line, or want to just simplify your life,
Call Oasis at (520) 648-1755!

How Often Should The Condensate Line Be Checked?

Check the condensate drain line monthly throughout the cooling season to ensure that collected moisture is draining properly. A clogged condensate drain can cost you big to repair water damage to your home– and it’s totally avoidable!

If you suspect you have a clogged drain line and need immediate assistance, contact
Oasis at (520) 648-1755 today!


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