No visible flow is shown in the flow meter:

 

Verify that that the generator is running and that all sampling line valves are physically open to the Simple Dew analyzer.  Disconnect the tubing to the filter and verify that there is flow coming out of the tubing (reference Figure 6).  If there is no flow at this point, there may be a blockage in the tubing or the supply pressure may be too low to flow through the filter and flow meter.  Isolate the sampling line by disconnecting it on both ends.  Blow clean, dry air through the sampling line to verify that it is clear.  Using a manometer, measure the supply pressure from the atmosphere generator.  If the supply pressure is less than 10” WC positive pressure, a pump may be required to pull a sample of gas through the Simple Dew analyzer.

 

Open the front door of the Simple Dew and disconnect the tubing to the bottom of the Sensor Sampling Block (reference Figure 7).  Verify that there is flow coming out of the tubing.  If there is no flow present, the filter may be clogged or very dirty preventing any flow past it.  The tubing between the filter and Sensor Sampling Block may also be clogged.  Remove the filter element and see if that solves the flow issue (reference Figure 5).  If so, replace the filter element with a new one.  If not, remove the tubing and blow clean, dry air through it to free it of any blockages.  Reinstall the tubing to the filter and verify flow through the flow meter to see if that fixed the flow issue.

 

Next, disconnect the tubing to the bottom of the sample flow meter (reference Figure 9).  Verify that there is flow coming out of the end of the tubing.  If there is no flow present, the Sensor Sampling Block may be clogged or very dirty preventing any flow through it.  Remove the dew point sensor, isolate the sampling block and blow air through it to remove the blockage (reference Figure 8).  Reinstall the dew point sensor and tubing to the Sensor Sampling Block and visually check to see if there is flow through the flow meter.  Reconnect the tubing to the flow meter.

 

Remove the tubing from the top of the flow meter (reference Figure 10).  Verify if there is any flow indicated through the flow meter.  Check the flow outlet to see if you can feel any flow.  If so, the flow meter flow indicating ball may be stuck.  Remove the sample supply tubing from the bottom of the flow meter isolating it.  Blow air through the flow meter to free the indicator ball.  If necessary, flow isopropyl alcohol through the meter and then flow air through the meter to free the ball.  Re-connect the sample supply tubing at the bottom of the meter and see if there is any flow shown through the meter.  If so, reconnect the sample tubing to the top of the meter.  If flow stops, the sample tubing out of the meter may be clogged.  Isolate that tubing and blow clean, dry air through the tubing.  Reconnect the tubing and check for flow.

 

Remove the sample tubing at the top of the Simple Dew where the sample exits the unit (reference Figure 10).  Blow air through that fitting to verify that there isn’t a blockage out of the Simple Dew analyzer.  Reconnect the tubing and verify flow through the unit.

 

(Figure references can be found here)