Teledyne 9110T - Nitrogen Oxides Analyzer - Manual (Page 248)

Model 9110T NOx Analyzer Instrument Maintenance
Teledyne Analytical Instruments 248
 The pressure differential between the test functions SAMP and RCEL increases significantly.
11.3.5.1. Procedure for Replacing Filters on External Pumps
1. Power down the analyzer and pump.
2. For internally mounted filters, skip the next two steps.
3. Remove the analyzer exhaust tube from the dust filter.
4. Remove the particle filter from the pump by pushing the white plastic ring into the
fitting and pulling the filter out of the fitting.
 If necessary, use needle-nose pliers to pry the filter out of the fittings.
5. Push a new filter into the pump fitting and ensure that the arrow on the filter points
towards the pump.
6. Push the exhaust tubing onto the filter. Skip the next two steps.
7. For internally mounted filters at the inside rear panel, remove the chassis and locate
the filter between the vacuum manifold and the exhaust port fitting.
8. Disconnect the clear tubing from the filter body and change the filter with the arrow
pointing against the gas flow. To remove the hose clamps, slide the two clamp
ends in opposite directions with a needle-nose pliers until the clamp comes apart.
Reconnect the tubing by using the same or new clamps and pushing tightening
them until a good seal is achieved.
9. Restart the pump and clear any error warnings from the front panel display.
10. After about 5 minutes, check the RCEL pressure reading and ensure that it is
similar to its value before changing the filter but less than 10 in-Hg-A.
11.3.5.2. Procedure for Replacing Filters on Internal Pumps
1. Power down the analyzer and pump.
2. Remove the chassis top and locate the filter between the vacuum manifold and the
exhaust port fitting.
3. Disconnect the clear tubing from the filter body and change the filter with the arrow
pointing against the gas flow.
4. To remove the hose clamps, slide the two clamp ends in opposite directions with a
needle-nose pliers until the clamp comes apart.
5. Reconnect the tubing by using the same or new clamps and pushing tightening
them until a good seal is achieved.
6. Restart the pump and clear any error warnings from the front panel display.
7. After about 5 minutes, check the RCEL pressure reading and ensure that it is
similar to its value before changing the filter (but less than 10 in-Hg-A).