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How to Unclog Central Vacuum System Pipes

Occasionally, central vacuum systems can become clogged—either in the pipes, vacuum head or the hose. Here are a few basics steps to unclog central vacuum system pipes:

  1. Determine the general location of the clog.

    You can determine the location of the clog by identifying which low performing inlet is closest to the main vacuum in the garage or basement.

  2. Insert the hose into the inlet valve with the clog as usual and place your hand over the handle end and let the pressure build up for a few seconds. Quickly release and repeat.

    Repeat this process for 10 minutes or until the clog is released.

  3. Use the power of reverse suction by inserting a portable vacuum or shop vac hose directly into the inlet valve(s) and let the pressure build. Quickly release and repeat.

    If the portable or shop vacuums are not powerful enough, then consider removing the central vacuum unit from the garage or basement and bringing it to the clogged inlet valve. Use the vacuum hose and your hand as a gasket to work the clog out.

  4. Run a Free Flow Maintenance Sheet through the clogged inlet valve(s) to clear the blockage.

    The sheet will act like a sail and more pressure will build up around the clog causing the powerful vacuum motor will pull harder and hopefully release the clog.

  5. Run electrician’s fish-tape or plumber’s snake and try to hook object/clog.
  6. If the clog still won’t come out, you will need to determine the exact location of the clog.

    Once the location is determined, more severe agitation can be applied or the pipe can be cut and reconnected using a single central vacuum coupling.

    The best way to find the exact location of the clog is by listening for a humming or vibration. In the late evening or early morning, before anyone is making noise in the home, connect the hose to the closest clogged inlet to the vacuum unit and turn it on. Go around and listen carefully, putting your ear to the wall, floor and ceiling, also listening in the basement and attic. You can create more noise by running a ping pong ball directly into the inlet (and then inserting and turning on the hose). The ping pong ball will dance around making more chatter. Once you have determined the exact location of the clog, you can cut the pipe and pull out the clog. Use a coupling to easily put the pipe back together. If you do not feel comfortable performing this on your own, contact one of our authorized dealers in your area.

If you believe that the clog is located in either the vacuum head or the hose, here are a few simple steps to take:

  • Hose
    The hose has to be checked without it being plugged into a wall valve because the pipes may be clogged. Check the hose by inserting it directly into the main vacuum unit in the garage or basement. Turn the unit on and feel the suction at the end of the hose handle. If there is no or low suction, then the clog is in the hose. You can remove the clog by running a long, stiff object through the hose, such as a butter knife, starting at the wall end. Another option would be to reverse the air flow through the hose by connecting the handle end into the intake on the main unit. With your hand acting as a gasket, let the suction move through the hose to pull the clog out.

  • Vacuum Head
    Start by isolating the carpet vacuum head and wands. Disconnect the wands and look through them and into the neck of the vacuum. If the clog is in the vacuum head or wands simply pull or push it out.

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