Understanding How your Air Conditioner’s PVC Drain Line Functions and What it’s For…

Home » Understanding How your Air Conditioner’s PVC Drain Line Functions and What it’s For…

What is a Air Conditioning drain line?

An air conditioner PVC drain line is a small pipe that transports water and debris from the condensate drain pan under the evaporator coil. The line runs from the indoor unit to the outside of the home. The line is typically made of PVC or metal. It has a slight downward slope to allow gravity to take the water down the drain and out of the home. The line also has a drain trap, also known as a P-trap. The inside diameter of the line should not be smaller than 3/4″. According to the IMC, 3/4″ is sufficient for up to 20 tons unless the drain outlet size is larger than 3/4″.

How to clean an Air Conditioning drain line and P-trap?

You can clean an AC drain line by pouring a mixture of equal parts vinegar and water down the line access port. Pour at least 1 cup down the access port and up to one gallon.

  • Turn off the air conditioner
  • Look for the access port
  • Use A Wet-Dry Vacuum (If Necessary)
  • Flush the drain line with distilled white vinegar
  • Repeat every 30 days during the summer

Access Port for HVAC system

Pouring vinegar in access port

What the Pros know about common drain line standards?

An air conditioner condensate line should drain to the outside of your home. The drain line often runs from the indoor unit to a white PVC pipe near the outdoor unit. The condensate line should be routed at least 12 inches from the foundation wall. Some municipalities require that condensate be disposed of in the sanitary sewer, while others require disposal to the building exterior or storm drainage piping. A normal air conditioner can produce 15-20 gallons of water per day. And, you can insulate the pipe to prevent the condensation from freezing.

How can I tell if my Air Conditioning drain line is clogged?

Many modern air conditioning units have sensors inside the drain pan that alerts you if a clog is detected in the drain. However, if you have an older unit without this feature, look for the following signs of a clogged drain line:

  • Full drain pan: If the drain line is clogged, water will back up into and fill up the drain pan.
  • Water around the indoor unit: If there’s water on the ground around your AC’s indoor evaporator coil unit, water may be overflowing from the drain pan because of a clog in the drain line.
  • AC won’t turn on: Some units have sensors inside the drain pan that shuts off power to the unit if it detects that the drain pan is full. This feature prevents water damage to the air conditioner and surrounding floor that may result from water overflowing from the pan.
  • Musty odor when the AC is running: Standing water inside the drain pan can cause mold and mildew to develop. If you smell a musty, mildewy odor in your home when the air conditioner is running, it’s likely because the moldy air inside the drain pan is circulating through your HVAC system.

Why is my Air Conditioning drain line clogged?

The moist environment of your air conditioner’s drain pan and drain line creates the perfect environment for mold and algae to develop. Over time, these substances can accumulate inside the drain line to the point that they clog it completely. In addition, dirt, debris, insects and other foreign objects may make their way into the line and cause it to clog.

Published by Juju

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