How to uncover a drain with pressurized air

A clogged drain can be a sore head for the owners of a house, especially when trying to decide what type of method used to unclog it. Even though there are many methods to uncover drainage, such as chemicals, snakes and plungers, many plumbers use the kinetic force to force compressed air to do so. With proper use of a ram pump, which you can rent at many hardware stores and shopping centers rent equipment, you can quickly and effectively, unclog a drain with pressurized air.


  1. Check the trap on the tube. Make sure it is not rusted or corroded. You must do this before attempting to unclog the pipe with pressurized air as if the trap is corroded, the pressurized air could break the entire trap.
  2. Run water slowly so that the pipe and drain begin to fill. If the drain is not completely covered, you must keep the water running as you complete the uncovering process. If the drain is completely obstructed, let the water flow until it fills the bottom of the sink slightly. If the sink has an opening, ask someone to hold a wet rag over it, otherwise, the air pressure will not affect the obstruction in the drain and will come out through the opening.
  3. Move the rubber mouth on the underside of the water pump over the mouth of the basin pipe and start pumping. Watch the reading on the pump to see the pressure. Try to pump at 20 psi to start.
  4. Pull the trigger toward you when the meter reaches 20 psi. You will feel a strong burst of air coming out of the pump and into the pipe. This should unlock even a large blockage, but if it does not, pump again at 20 or 25 psi and pull the trigger. Repeat until the burst of air removes the plug in the drain.
  5. Run the water for at least 10 minutes after unclogging the drain to make sure it runs out of your pipe system.