Proform 622 Exp treadmill belt slips
If the walking belt slips when walked on, first remove
the key and UNPLUG THE POWER CORD.
Using the hex key, turn both rear roller bolts clockwise,
1/4 of a turn. When the walking belt is correctly
tightened, you should be able to lift each edge of the
walking belt 2 to 3 inches above the walking platform.
Be careful to keep the walking belt centered. Then,
plug in the power cord, insert the key, and carefully
walk on the treadmill for a few minutes. Repeat until
the walking belt is properly tightened. Now if this does not solve this problem then check the drive belt and adjust accordingly, also reverse the process of the above mentioned Read More At : Proform 622 Exp Treadmill Rear Roller...