Operational Life - Honeywell Sensepoint Technical Manual

Maintenance

Operational Life

The pellistors used in the flammable gas sensor can suffer from a loss of sensitivity when
in the presence of poisons or inhibitors, e.g. silicones, sulfides, chlorine, lead or halogenated
hydrocarbons.
The pellistors are poison resistant to maximize the operational life of the flammable sensor.
A typical operating life, subject to the presence of poisons/inhibitors is in excess of 3 years.
The operational life of toxic sensors depends on the application, frequency and amount of
gas exposure.
Under normal conditions both the carbon monoxide and hydrogen sulfide sensors have an
expected operating life of greater than 24 months.
The oxygen, hydrogen, chlorine, sulfur dioxide, nitrogen dioxide, and ammonia sensors have an
expected operating life of greater than 12 months.
When the sensor has passed its useful operating life replace it by following the subsequent
procedure.
2106M0525 Iss 2 Nov 05 21