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Damien McCusker, Manager of Arpi's residential service division, has been working in the HVAC industry for 16 years and has hands-on experience in new home installations, furnace and air conditioner replacements, sales and residential service. He spends most of his spare time being an UBER driver, driving his kids to soccer practice and games.

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These are the Warning Signs of Poorly-Vented Drain Lines


These are the Warning Signs of Poorly-Vented Drain LinesPoorly-vented drain lines in your home can mimic other plumbing problems and even lead to futile attempts to clear blockages that aren’t there. Your plumbing drain system requires air to operate properly. As drain water flows through the pipes, pressure imbalances occur. Drain vents are open pipes that connect to drain lines and extend all the way up to the roof to allow air into and out of the system to equalize pressure. When these vent pipes become obstructed — typically by causes like birds nests, accumulation of leaves or other debris or internal deterioration of the pipe — a number of signs can occur.

If any of these plumbing symptoms sound familiar, have a qualified plumber check for poorly-vented drain lines in your home:

  • Sinks or tubs always drain sluggishly — Often, the assumption is that the drain pipe may be partially clogged. However, plunging and other methods typically fail to have any effect. Pressure inside the drain pipe caused by inadequate venting is creating a vacuum that impedes the flow of wastewater.
  • Gurgling noises from inside a drain — As waste water moves through an unvented pipe, accumulating pressure may vent upwards through an empty drain pipe. You’ll hear gurgling or belching sounds when it happens.
  • Bubbles in the toilet — Air trapped inside a drain pipe due to a blocked vent may be pushed up through the toilet, appearing as bubbles in the toilet bowl.
  • Sewer odors — The unmistakeable pungent smell of sewer gas may drift up out of empty drain pipes when inadequate venting allows fumes from the sewer line to flow backwards into the house.

Resolving poorly-vented drain lines usually requires a procedure to inspect the pipe, locate the blockage, then clear the vent pipe. Much of this must be done up on the roof where plumbing vent pipes terminate and requires specialized equipment. Due to safety issues, it’s not a DIY project and should be left to a professional plumber.

If you suspect poorly-vented drain lines in your home, contact Arpi's Industries in Calgary for professional diagnosis and repair.

Our goal is to help educate our customers in Calgary, Alberta about energy and home comfort issues (specific to HVAC systems). For more information about drain lines and other HVAC topics, download our free Home Comfort Guide.

Credit/Copyright Attribution: “NarisaFotoSS/Shutterstock”

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