Mixing Sensors is a Crap Shoot
Your oxygen sensors are the heart of your CCR, offering critical information about your life support status. Attempting to save money by stretching your sensors beyond their service life may greatly increase your diving risks.
Teledyne stopped supplying sensors to the diving market quite a while ago. If your rebreather contains any Teledyne sensors, they are beyond their expiration, whether they have just been installed recently or not. While you are checking your sensors, ensure that you have not mixed different brands within your rebreather. Your three sensors should be of the same brand. Each manufacturer has a proprietary algorithm that compensates for temperature changes within the unit. If you mix brands you may find that they drift apart through the duration of your dive. This might not be attributed to depth, but rather temperature changes. Ensure the sensors within your rig are made by one manufacturer and are approved by the manufacturer of the unit.
It is critical that these sensors were tested by the CCR manufacturer. CE standards ensure these critical tests have been completed. If your rebreather is not CE EN:14143 approved, then contact the manufacturer for verification of their test protocols for sensors and the approved brands that are documented through their testing. If your sensors are in good order, risks are reduced and without reliable sensors, its all a crap shoot.
