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Dust-Stopper
The dust-stopper is a filter with a large surface area on which dust can collect without
slowing the sampling rate of the Gas-Ranger. The filter element is easily cleaned or replaced by
removing the threaded cap and either blowing off the filter element or pulling it off and
replacing. Replacement dust filter cartridges are available as Part No. DF-105. The dust-stopper
should be used between the dust and water-block filter and the probe or water-stopper.
Flue Gas Filter
This filter is designed to be screwed finger-tight between the telescoping metal probe and
the dust and water-block filter. It must be used for CO measurements in flue gas and may also be
used for CO measurements in ambient air. The filter cartridge should be replaced when about
90% of the material has changed color from purple to brown or when it becomes blocked by soot
or water. Replacement flue gas filters are available as Part No. FF-005 (package of 5 filters).
Heavy Hydrocarbon Filter
A heavy hydrocarbon filter, filled with activated carbon, is designed to be used with the
standard probe or the bar hole probe on a one-time-only basis. Activated carbon adsorbs gasoline
and other heavy hydrocarbons (for example, propane or butane) which interfere with methane
detection. In order to keep the filter material from adsorbing hydrocarbons prior to use, the filter
is fitted with plastic endcaps which must be removed just before use. The filter should be either
discarded after use or refilled with activated carbon and recapped with the plastic endcaps. This
filter is designed to be screwed finger-tight between the probe and the dust and water-block filter.
Heavy hydrocarbon filters are available as Part No. HF-005 (package of 5 filters).
The heavy hydrocarbon filter can also remove some alcohols and unsaturated
hydrocarbons which can interfere with CO readings. The filter should be discarded or refilled
after each use.
Activated carbon for refilling approximately 50 cartridges is available as Part No. HR-
050. To refill the filter cartridge, remove threaded top and pour out spent filter material.
Retrieve the plastic retainer disk from the spent filter material. Fill cartridge with fresh filter
material to bottom of threads and place the plastic retainer disk flat on top of the filter material.
Screw in top until finger tight and check seal with block tests.
CAUTION:
Do not remove or puncture the white filter in the bottom of the filter cartridge.
If this filter becomes damaged, discard the filter cartridge.
