Why is it Important for the Condensate Line to Drip?

by | Aug 14, 2018 | HVAC Blog

Manage Monsoon Moisture Madness!

Monsoon season is the wettest most humid time of the year in Southern Arizona. You might normally feel comfortable somewhere between 68’ and 77’, and like most people, set your thermostat at the most economical point within your comfort range. When it’s humid 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. The longer the air conditioner runs, the dryer air becomes and the less sticky you feel!

What Is A Condensate Drain?

When it’s steamy your AC works overtime to remove water vapor from the air -but where does all the water vapor go? Moisture in the air is condensed on the evaporator coil, beads up – just like the drips on the side of a cold glass of beer, and the precipitate is collected in a pan. The pan is drained by gravity, or is pumped out, through a small PVC pipe called the “condensate line” or “condensate drain.” A little clog in your condensate drain can create a huge problem!

Why Is A Clogged Drain A Problem?

When the condensate 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 ductwork and HVAC equipment and hundreds of dollars-worth of damage to drywall, carpentry and flooring.
A partially blocked, poorly draining condensate line can decrease the effectiveness of your otherwise highly efficient air conditioning equipment and cause musty odors from bacteria, algae and mold growth.

ceiling water damage

How Does a Condensate Drain Get Clogged?

If the condenser coils are dirty, (and without maintenance they will eventually get filthy dirty) the condensate will carry dirt, pet hair and debris into the condensate drain which could cause it to become encrusted or even totally clogged. Algae will find this medium particularly cozy, especially during the warm moist weather, and grow in chunks which can rapidly block the drain.

blogged line

Three Ways to Know If The Condensate Drain Is Clogged

#1 No cooling could be the first sign of a backed-up condensate line because some units have an overflow safety switch which simply 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 valve

#2 The condensate line is not dripping. The 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! If there is standing water in the drain pan, your condensate drain is clogged!

#3 Dripping from anywhere else is a problem. Look for water coming from the bottom of the cabinet or exhaust fans. Act quickly if you notice any water spots or damage to the ceilings, carpet or furnishings near the AC. When an AC system is mounted above a furnace you might see rust forming on the furnace below it. Always remember water and electricity Do Not Mix!  Call your professional at Oasis when in doubt.

How to Clean Out Your Condensate Drain

  • Turn off the power to your HVAC system at the breaker and the thermostat.
  • 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.
  • 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.
  • Clean the pan with soap and water.
  • Find the condensate drain outlet which might be located outside your house near the foundation. Often the clogged drain can be cleared with wet/dry vacuum suction. You can also try removing the clog with a plumber’s snake.
  • 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.

    Condensate Safety Valve

  • 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 AC condensate drain
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 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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