Check to see if drain channel is full of water.
Insert a stiff cord or belt into pipe.
If the belt can pass through the pipe, it is
blocked with soft food material.
Twist the belt to loosen food material stuck on
pipe wall, then use water to flush food material out of pipe.
If belt could not pass through the drain pipe
and water is still in channel, mark the belt
at blockage point.
Measure the length.
Step 7
Compare the length with data on drawing and
check the usage time.