- 1). Check your equipment. Your pressure jet should be able to handle water pressure up to around 2,500 psi. The degree of pressure you use will depend on the nature of the blockage as well as the material that makes up the pipe. For softer pipes or less solid clogs, a lighter psi should be used -- 1,500 is recommended by UltimateWasher.com.
- 2). Insert the nozzle of the pressure washer beneath the manhole cover of the affected sewer. The hose itself should be protected by a thicker portion of hose which acts as a shock absorber as well as preventing friction between the hose and the sides of the sewer line.
- 3). Set the pressure washer to the appropriate setting. For example, an industrial sewer with reinforced walls may require pressure up to 2,500 psi. The same may be true if the blockage is solid, such as a tree root. The septic system of a private residence would require a lighter psi.
- 4). Turn on the pressure washer. Be careful to keep the nozzle under tight control as it moves in a rotating motion, clearing blockages from the sewer.
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