1. The ozone lamp will die after many years of service
• but along the way, it will begin to decrease its ozone (O3) production and you WILL experience Ozone Starvation (see other FAQ)
• The ozone lamp power supply might live long enough to power two or three lamps
2. The Darlington Pair power transistor that controls current to the sensor chip’s Peltier cooler will fail sometimes age;
• sometimes the Peltier chip pulls too much current;
• sometimes a technician will unplug and re-plug the Darlington cable and blow the transistor (I’ve done this at least once)
3. When reassembling, technicians can cause stress on the ACU02 (the CPU / controller board that sits on top of the BPR (backpressure regulator)) by not routing the ribbon cables neatly; this will break solder connections on some very sensitive chips causing hard failures or the very frustrating intermittent failures.
4. The capillary will foul causing a loss of sensitivity.5. The heaters in the reaction chamber are covered with termite paste; the paste will dry out over time causing poor thermal conduction. This could induce an instability in the temperature control of the “block” (the upper region of the reaction chamber); and this could induce variations in zero, span, and process readings.
6. [later]
7. [later]