Replacement of the optical sensor is simple and the process is identical for any Hybrid Series rower equipped with older-style A1 QuickStart and A1 Pro Monitors.
The 2-piece optical sensor design features a sensor cover plate and separate sensor assembly. (Newer-style sensors are a one-piece design with the sensor integrated in the cover plate.)
To install, follow the steps below.

Step 1
Remove the handle from the handle rests and place the handle in the full position as shown.

Step 2
Remove the top 2 tie rods and both JCBs connecting the top deck to the tank assembly as shown.

Step 3
Gently lift the top deck, taking care not to dislodge the guide pulleys.
Unclip the sensor wire from the monitor wire. Set the top deck to the side.

Step 4
Remove the 3 screws holding the sensor cover plate to the bottom of the top deck. Remove the staple holding the sensor wire to the top deck.
Note: Older Hybrid Series rowers marketed as “GX” and “A1” had a 1-piece sensor design without the cover plate — skip this step if that is the case for your rower.

Step 5
To remove the sensor, simply pull it out. It’s a snug fit, but doesn’t require much effort to take out.

Step 6
Replace the old sensor by pressing the new one into place. You can use a piece of tape to hold the wire to the top deck. Replace the sensor cover plate and screws.

Step 7
Reconnect the sensor and monitor wires, then gently fit the top deck back into place.

Step 8
Re-attach the top deck on the tank assembly by securing it with the JCBs and tie rods / barrel nuts.
Note: The barrel nuts have a slot in the bottom that aligns with the hole the tie rod bolts screw in to — this will assist you with installation.