Check that the orange electronics head O-rings and flat seal are clean and lubricated. Dive Rite recommends lubricating these seals with Tribolube 71 grease.
Confirm that the small orange O-ring is in place on the premix tube. The O-ring should be above the sensor disk. To ensure that it is in the right spot, lay your fingers on the disk and the O-ring should be above your fingers (See Figure 15). When the canister is installed it will push the O-ring down to seal against the stainless steel tube in the center of the canister.
Install the head by inserting the premix tube into the center tube of the body, aligning the arrows on the head and body (See Figure 16), pushing the head into position, and then rotating clockwise until the head arrow is aligned with the “LOCKED” position (See Figure 17).
Figure 18 shows the complete scrubber assembly. With both the head and the end cap installed, it is possible to pressure test the canister by covering one of the loop hose fittings with your hand and blowing into the other. No air should escape. If you hear or feel air leaking, remove the head and lid and confirm that all seals and O-rings are installed and properly cleaned and lubricated.