35-3010RK-07 Sample-Draw Detector • 3
Flow System
The sample draw detector’s flow system consists of the INLET fitting, hydrophobic filter,
charcoal filter, pump, flowmeter, bypass valve, status lights, pressure switch, flow blocks,
and EXHAUST fitting (see Figure 1). Figure 2 illustrates how the gas sample moves
through the flow system.
Figure 2: Sample Draw Detector Flow Diagram
INLET Fitting
The INLET fitting on the bottom of the housing allows the gas sample to enter the sample
draw detector. The INLET fitting accepts 1/4 in. rigid tubing. See “Installation” on page 8
for instructions to connect tubing to the INLET fitting.
Hydrophobic Filter
The hydrophobic filter is to the left of the main circuit board. It is held in place by a metal
clip. It prevents water and other liquids from contaminating the flow system. Replace the
filter when it appears dirty, discolored, or clogged. If a liquid other than water is drawn
into the filter, replace the filter as soon as possible.
Oxygen
IR CH4
Hydrophobic
Filter
Inlet
Exhaust
Pump
LEL
Dummy
Plug
H2S
Flow meter
Flow Block
Bypass
Valve
Pressure Switch
CO
Dummy
Plug
Charcoal
Filter
